ASTM E363-23

Standard Test Methods for Chemical Analysis of Chromium and Ferrochromium

SIGNIFICANCE AND USE
4.1 These test methods for the chemical analysis of chromium metal and ferrochromium alloy are primarily intended to test such materials for compliance with compositional specifications such as Specifications A101 and A481. It is assumed that all who use these test methods will be trained analysts capable of performing common laboratory procedures skillfully and safely. It is expected that work will be performed in a properly equipped laboratory.
SCOPE
1.1 These test methods cover the chemical analysis of chromium and ferrochromium having chemical compositions within the following limits:    
Element  
Composition, %  
Aluminum  
0.25 max  
Antimony  
0.005 max  
Arsenic  
0.005 max  
Bismuth  
0.005 max  
Boron  
0.005 max  
Carbon  
9.00 max  
Chromium  
51.0 to 99.5  
Cobalt  
0.10 max  
Columbium  
0.05 max  
Copper  
0.05 max  
Lead  
0.005 max  
Manganese  
0.75 max  
Molybdenum  
0.05 max  
Nickel  
0.50 max  
Nitrogen  
6.00 max  
Phosphorus  
0.03 max  
Silicon  
12.00 max  
Silver  
0.005 max  
Sulfur  
0.07 max  
Tantalum  
0.05 max  
Tin  
0.005 max  
Titanium  
0.50 max  
Vanadium  
0.50 max  
Zinc  
0.005 max  
Zirconium  
0.05 max  
1.2 The analytical procedures appear in the following order:    
Sections  
Arsenic by the Molybdenum Blue Spectrophotometric Test Method
[0.001 % to 0.005 %]  
10 – 20  
Lead by the Dithizone Spectrophotometric Test Method
[0.001 % to 0.05 %]  
21 – 31  
Chromium by the Sodium Peroxide Fusion-Titrimetric Test Method
[50.0 % to 99.5 %]  
32 – 38  
1.3 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Section 6 and in special “Warning” paragraphs throughout these test methods.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 30-Jun-2023
• ICS: 77.040.30 - Chemical analysis of metals
• Technical Committee: E01 - Analytical Chemistry for Metals, Ores, and Related Materials
• Drafting Committee: E01.01 - Iron, Steel, and Ferroalloys

Relations

• Refers: ASTM A481-05(2020) - Standard Specification for Chromium Metal
• Effective Date: 01-Mar-2020
• Refers: ASTM E135-20 - Standard Terminology Relating to Analytical Chemistry for Metals, Ores, and Related Materials
• Effective Date: 01-Jan-2020
• Refers: ASTM E1601-19 - Standard Practice for Conducting an Interlaboratory Study to Evaluate the Performance of an Analytical Method
• Effective Date: 01-Nov-2019
• Refers: ASTM A101-04(2019) - Standard Specification for Ferrochromium
• Effective Date: 01-Nov-2019
• Refers: ASTM E135-19 - Standard Terminology Relating to Analytical Chemistry for Metals, Ores, and Related Materials
• Effective Date: 15-May-2019
• Refers: ASTM E50-17 - Standard Practices for Apparatus, Reagents, and Safety Considerations for Chemical Analysis of Metals, Ores, and Related Materials
• Effective Date: 01-Sep-2017
• Refers: ASTM E50-11(2016) - Standard Practices for Apparatus, Reagents, and Safety Considerations for Chemical Analysis of Metals, Ores, and Related Materials
• Effective Date: 01-Aug-2016
• Refers: ASTM E135-16 - Standard Terminology Relating to Analytical Chemistry for Metals, Ores, and Related Materials
• Effective Date: 15-May-2016
• Refers: ASTM A481-05(2015) - Standard Specification for Chromium Metal
• Effective Date: 01-Nov-2015
• Refers: ASTM E135-15a - Standard Terminology Relating to Analytical Chemistry for Metals, Ores, and Related Materials
• Effective Date: 01-Jul-2015
• Refers: ASTM E135-15 - Standard Terminology Relating to Analytical Chemistry for Metals, Ores, and Related Materials
• Effective Date: 15-May-2015
• Refers: ASTM A101-04(2014) - Standard Specification for Ferrochromium
• Effective Date: 01-Oct-2014
• Refers: ASTM A101-04(2014)e1 - Standard Specification for Ferrochromium
• Effective Date: 01-Oct-2014
• Refers: ASTM E135-14b - Standard Terminology Relating to Analytical Chemistry for Metals, Ores, and Related Materials
• Effective Date: 15-Aug-2014
• Refers: ASTM E135-14a - Standard Terminology Relating to Analytical Chemistry for Metals, Ores, and Related Materials
• Effective Date: 01-Apr-2014

Overview

ASTM E363-23: Standard Test Methods for Chemical Analysis of Chromium and Ferrochromium provides comprehensive procedures for determining the chemical composition of chromium metal and ferrochromium alloys. The test methods included in this standard are primarily intended for confirming compliance with compositional specifications such as those outlined in ASTM A101 (Ferrochromium) and ASTM A481 (Chromium Metal). These analytical methods ensure quality control and support process optimization in industries reliant on chromium and ferrochromium materials.

This standard is developed under ASTM Committee E01 and aligns with internationally recognized principles for standardization, ensuring global relevance and regulatory compliance. The standard assumes that users are skilled analysts working in well-equipped laboratories and underscores the importance of safety and environmental practices.

Key Topics

Main Elements Analyzed

• Chromium (51.0 - 99.5%)
• Carbon (up to 9.00%)
• Silicon (up to 12.00%)
• Aluminum, Cobalt, Copper, Manganese, Nickel, Nitrogen, Phosphorus, Sulfur, Titanium, Vanadium, Zirconium, and other trace elements with specified maximum limits

Test Methods Covered

• Arsenic by the Molybdenum Blue Spectrophotometric Test Method: For determining arsenic content ranging from 0.001% to 0.005% in chromium and ferrochromium.
• Lead by the Dithizone Spectrophotometric Test Method: For analyzing lead concentrations from 0.001% to 0.05%.
• Chromium by the Sodium Peroxide Fusion-Titrimetric Test Method: For chromium measurement between 50% and 99.5% content.

Key Procedures and Considerations

• Procedures specify apparatus, reagents, safety precautions, and spectrophotometric practices.
• Emphasis on use of SI units only.
• Guidance for the preparation of calibration curves, sample handling, and data interpretation.
• Instructions on appropriate laboratory safety and environmental practices, with detailed hazard statements referenced throughout the document.

Applications

Industrial and Laboratory Uses

• Quality control in alloy production: These test methods are critical for verifying the composition of chromium and ferrochromium used in steelmaking, manufacturing of superalloys, and specialized metallurgical processes.
• Material certification and purchasing: Compliance with ASTM E363-23 is often required for product acceptance in international supply chains, ensuring that materials meet required composition limits.
• Research and development: The standard supports analytical chemistry labs and R&D teams in developing new chromium-based materials and alloys.
• Regulatory and environmental monitoring: Accurate chemical analysis helps facilities comply with environmental and safety regulations related to trace element content in metallic products.

Benefits

• Ensures compositional accuracy for critical elements, minimizing the risk of defective materials in end-use applications.
• Facilitates global trade by providing a recognized and harmonized method for chemical analysis.
• Supports inter-laboratory consistency through standardized test procedures.

Related Standards

When utilizing ASTM E363-23 for chemical analysis of chromium and ferrochromium, also consider referencing these related ASTM standards:

• ASTM A101: Specification for Ferrochromium
• ASTM A481: Specification for Chromium Metal
• ASTM D1193: Specification for Reagent Water (for analytical procedures)
• ASTM E29: Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
• ASTM E32: Sampling of Ferroalloys and Steel Additives
• ASTM E50: Safety and Apparatus Guidelines for Chemical Analysis of Metals
• ASTM E60: Spectrophotometric Analysis of Metals
• ASTM E135: Analytical Chemistry Terminology for Metals and Ores
• ASTM E1601: Interlaboratory Study Practices

By following ASTM E363-23 and related standards, laboratories and manufacturers ensure accurate, reliable, and internationally accepted chemical analysis of chromium and ferrochromium, supporting both quality assurance and compliance efforts worldwide.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E363 − 23
Standard Test Methods for
Chemical Analysis of Chromium and Ferrochromium
This standard is issued under the fixed designation E363; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
1.1 These test methods cover the chemical analysis of
mine the applicability of regulatory limitations prior to use.
chromium and ferrochromium having chemical compositions
Specific hazard statements are given in Section 6 and in special
within the following limits:
“Warning” paragraphs throughout these test methods.
Element Composition, %
1.5 This international standard was developed in accor-
Aluminum 0.25 max
Antimony 0.005 max
dance with internationally recognized principles on standard-
Arsenic 0.005 max
ization established in the Decision on Principles for the
Bismuth 0.005 max
Development of International Standards, Guides and Recom-
Boron 0.005 max
Carbon 9.00 max mendations issued by the World Trade Organization Technical
Chromium 51.0 to 99.5
Barriers to Trade (TBT) Committee.
Cobalt 0.10 max
Columbium 0.05 max
2. Referenced Documents
Copper 0.05 max
Lead 0.005 max
2.1 ASTM Standards:
Manganese 0.75 max
Molybdenum 0.05 max
A101 Specification for Ferrochromium
Nickel 0.50 max
A481 Specification for Chromium Metal
Nitrogen 6.00 max
D1193 Specification for Reagent Water
Phosphorus 0.03 max
Silicon 12.00 max
E29 Practice for Using Significant Digits in Test Data to
Silver 0.005 max
Determine Conformance with Specifications
Sulfur 0.07 max
E32 Practices for Sampling Ferroalloys and Steel Additives
Tantalum 0.05 max
Tin 0.005 max
for Determination of Chemical Composition
Titanium 0.50 max
E50 Practices for Apparatus, Reagents, and Safety Consid-
Vanadium 0.50 max
erations for Chemical Analysis of Metals, Ores, and
Zinc 0.005 max
Zirconium 0.05 max
Related Materials
1.2 The analytical procedures appear in the following order: E60 Practice for Analysis of Metals, Ores, and Related
Materials by Spectrophotometry
Sections
Arsenic by the Molybdenum Blue 10 – 20
E135 Terminology Relating to Analytical Chemistry for
Spectrophotometric Test Method
Metals, Ores, and Related Materials
[0.001 % to 0.005 %]
E173 Practice for Conducting Interlaboratory Studies of
Lead by the Dithizone Spectrophotometric Test 21 – 31
Method
Methods for Chemical Analysis of Metals (Withdrawn
[0.001 % to 0.05 %] 3
1997)
Chromium by the Sodium Peroxide Fusion- 32 – 38
E1601 Practice for Conducting an Interlaboratory Study to
Titrimetric Test Method
[50.0 % to 99.5 %]
Evaluate the Performance of an Analytical Method
1.3 Units—The values stated in SI units are to be regarded
3. Terminology
as standard. No other units of measurement are included in this
standard.
3.1 For definition of terms used in this test method, refer to
1.4 This standard does not purport to address all of the
Terminology E135.
safety concerns, if any, associated with its use. It is the
1 2
These test methods are under the jurisdiction of ASTM Committee E01 on For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Analytical Chemistry for Metals, Ores, and Related Materials and are the direct contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
responsibility of Subcommittee E01.01 on Iron, Steel, and Ferroalloys. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved July 1, 2023. Published July 2023. Originally approved the ASTM website.
in 1970. Last previous edition approved in 2022 as E363 – 22. DOI: 10.1520/E0363- The last approved version of this historical standard is referenced on
23. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E363 − 23
4. Significance and Use Method, unless an alternative rounding method is specified by
the customer or applicable material specification.
4.1 These test methods for the chemical analysis of chro-
mium metal and ferrochromium alloy are primarily intended to
9. Interlaboratory Studies
test such materials for compliance with compositional specifi-
9.1 These test methods have been evaluated in accordance
cations such as Specifications A101 and A481. It is assumed
with Practice E173, unless otherwise noted in the Precision and
that all who use these test methods will be trained analysts
Bias section. Practice E173 has been replaced by Practice
capable of performing common laboratory procedures skill-
E1601. The Reproducibility R corresponds to the Reproduc-
fully and safely. It is expected that work will be performed in 2
ibility Index R of Practice E1601. The Repeatability R of
a properly equipped laboratory. 1
Practice E173 corresponds to the Repeatability Index r of
Practice E1601.
5. Apparatus, Reagents, and Spectrophotometric Practice
5.1 Apparatus, standard solutions, and other reagents re-
quired for each determination are listed in separate sections
ARSENIC BY THE MOLYBDENUM BLUE
preceding the procedure. Spectrophotometers shall conform to
SPECTROPHOTOMETRIC TEST METHOD
the requirements prescribed in Practice E60. (See 5.1.1.)
10. Scope
5.1.1 In these methods, cells utilized to contain the refer-
ence material and sample solutions in spectrophotometers are
10.1 This test method covers the determination of arsenic in
referred to as “absorption cells.” The radiant energy passed
chromium and ferrochromium in compositions from 0.001 %
through the cells can be measured as absorbance or transmit-
to 0.005 %.
tance. These methods refer to absorbance measurements. Refer
to Practice E60 for details.
11. Summary of Method
5.2 Spectrophotometric practices prescribed in these test
11.1 Arsenic is first separated by distillation as the trivalent
methods shall conform to Practice E60.
chloride. Ammonium molybdate is added to form
arsenomolybdate, which is then reduced by hydrazine sulfate
5.3 Purity of Water—Unless otherwise indicated, references
to form the molybdenum blue complex. Spectrophotometric
to water shall be understood to mean reagent water conforming
absorbance measurement is made at 850 nm.
to Type I or Type II of Specification D1193. Type III or Type
IV may be used if they effect no measurable change in the
12. Concentration Range
blank or sample.
12.1 The recommended concentration range is 0.01 mg to
5.4 Purity of Reagents—Reagent grade chemicals shall be
0.15 mg of arsenic per 50 mL of solution using a 1 cm cell.
used in all tests. Unless otherwise indicated, it is intended that
(See Note 1.)
all reagents conform to the specifications of the Committee on
Analytical Reagents of the American Chemical Society where NOTE 1—This test method has been written for cells having a 1 cm light
path. Cells having other dimensions may be used, provided suitable
such specifications are available. Other grades may be used,
adjustments can be made in the amount of sample and reagents used.
provided it is first ascertained that the reagent is of sufficiently
high purity to permit its use without lessening the accuracy of
13. Stability of Color
the determination.
13.1 The color is stable for at least 2 h.
6. Hazards
14. Interferences
6.1 For precautions to be observed in the use of certain
14.1 The elements ordinarily present do not interfere if their
reagents in these test methods, refer to Practices E50.
compositions are under the maximum limits shown in 1.1.
6.2 Specific hazard statements are given in 27.1, 27.7, and
36.2. 15. Apparatus
15.1 Distillation Apparatus, Fig. 1.
7. Sampling
15.2 Zirconium Crucibles, 30 mL capacity.
7.1 For procedures to sample the material, and particle size
requirements of the sample, refer to Practices E32.
16. Reagents
16.1 Ammonium Bromide (NH Br).
8. Rounding Calculated Values 4
16.2 Ammonium Molybdate Solution (10 g ⁄L)—Dissolve
8.1 Rounding of test results obtained using this test method
2.5 g of ammonium heptamolybdate tetrahydrate
shall be performed as directed in Practice E29, Rounding
((NH ) Mo O • 4H O) in 40 mL of warm water. Add 128 mL
4 6 7 24 2
of H SO (1 + 3), dilute to 250 mL, and mix.
2 4
Reagent Chemicals, American Chemical Society Specifications, American
16.3 Ammonium Molybdate-Hydrazine Sulfate Solution—
Chemical Society, Washington, DC., www.acs.org . For suggestions on the testing
Dilute 100 mL of ammonium molybdate solution to 900 mL,
of reagents not listed by the American Chemical Society, see the United States
add 10 mL of hydrazine sulfate solution, dilute to 1 L, and mix.
Pharmacopeia and National Formulary, U.S. Pharmacopeial Convention, Inc.
(USPC), Rockville, MD, www.usp.org. Do not use a solution that has stood more than 1 h.
E363 − 23
FIG. 1 Arsenic Distillation Apparatus
16.4 Arsenic, Standard Solution A (1 mL = 0.10 mg As)— 17.3 Color Development—Heat the flask in a boiling water
Transfer 0.1320 g of arsenic trioxide (As O ) to a 1 L volu- bath for 15 min. Remove the flask, cool to room temperature,
2 3
metric flask, dissolve in 100 mL of HCl, cool, dilute to volume, dilute to volume with ammonium molybdate-hydrazine sulfate
and mix. solution, and mix.
16.5 Arsenic, Standard Solution B (1 mL = 0.01 mg As)— 17.4 Spectrophotometry:
Using a pipet, transfer 100 mL of arsenic solution A (1 mL =
17.4.1 Multiple-Cell Spectrophotometer—Measure the cell
0.10 mg As) to a 1 L volumetric flask, dilute to volume, and
correction using absorption cells with a 1 cm light path and a
mix.
light band centered at 850 nm. Using the test cell, take the
spectrophotometric absorbance readings of the calibration
16.6 Hydrazine Sulfate ((NH ) •H SO ).
2 2 2 4
solutions.
16.7 Hydrazine Sulfate Solution (1.5 g ⁄L)—Dissolve 1.5 g
17.4.2 Single-Cell Spectrophotometer—Transfer a suitable
of hydrazine sulfate ((NH ) •H SO ) in water, dilute to 1 L,
2 2 2 4
portion of the reference solution to an absorption cell with a
and mix. Do not use a solution that has stood more than 1 day.
1 cm light path and adjust the spectrophotometer to the initial
setting, using a light band centered at 850 nm. While main-
16.8 Sodium Carbonate (Na CO ).
2 3
taining this adjustment, take the spectrophotometric absor-
16.9 Sodium Peroxide (Na O ).
2 2
bance readings of the calibration solutions.
17.5 Calibration Curve—Plot the net spectrophotometric
17. Preparation of Calibration Curve
absorbance readings of the calibration solutions against milli-
17.1 Calibration Solutions:
grams of arsenic per 50 mL of solution. Follow the instrument
17.1.1 Using pipets, transfer (1, 2, 5, 10, and 15) mL of
manufacturer’s instructions for generating the calibration
arsenic Solution B (1 mL = 0.01 mg As) to 125 mL Erlenmeyer
curve.
flasks.
17.1.2 Add 10 mL of HNO and evaporate the solution to
3 18. Procedure
dryness on a hot plate. Bake for 30 min at 150 °C to 180 °C.
18.1 Test Solution:
Remove from the hot plate. Add 45 mL of ammonium
18.1.1 Select and weigh a sample to the nearest 0.2 mg as
molybdate-hydrazine sulfate solution to each flask, warm
follows:
gently to dissolve the residue, and transfer the solution to a
As, % Sample Mass, g
50 mL volumetric flask. Proceed as directed in 17.3.
0.001 to 0.015 0.500
17.2 Reference Solution—Transfer 10 mL of HNO to a 0.01 to 0.04 0.250
0.035 to 0.10 0.125
125 mL Erlenmeyer flask and proceed as directed in 17.1.2.
E363 − 23
TABLE 1 Statistical Information—Arsenic
18.1.1.1 Transfer the sample to a 30 mL zirconium crucible
containing 10 g of Na O and 1 g of Na CO if ferrochromium, Repeatability Reproducibility
2 2 2 3
Ferroalloy Type As Found, % (R , Practice (R , Practice
1 2
or 8 g of Na O plus 2 g of Na CO if chromium metal.
2 2 2 3
E173) E173)
1. 70Cr-1Si-5C 0.0015 0.0001 0.0005
18.1.2 Mix thoroughly with a metal spatula. Fuse carefully
over a free flame by holding the crucible with a pair of tongs
and slowly revolving it around the outer edge of the flame until
the contents have completely melted; raise the temperature where:
gradually to avoid spattering. When the contents are molten,
A = milligrams of arsenic found in 50 mL of final test
give the crucible a rotary motion to dissolve any undissolved
solution,
particles of the alloy adhering to the bottom or sides. Finally, B = grams of sample represented in 50 mL of final test
increase the temperature until the crucible is bright red for solution, and
10 = conversion factor from mg to percent.
1 min. Cool the crucible to room temperature. Transfer the
crucible to an 800 mL beaker containing 60 mL of H SO (1 +
2 4
20. Precision and Bias
1) and 200 mL of water. Dissolve the melt; remove and rinse
20.1 Precision—Nine laboratories cooperated in testing this
the crucible.
test method and obtained the data summarized in Table 1.
18.1.3 If manganese dioxide is present, add H SO drop-
2 4
Samples with arsenic compositions near the upper limit of the
wise until the solution clears.
scope were not available for testing. The user is cautioned to
18.1.4 Heat to boiling, and cool. While stirring vigorously,
verify, by the use of reference materials, if available, that the
add NH OH until the solution is alkaline to litmus, and then
precision of this test method is adequate for the contemplated
add 3 mL to 5 mL in excess. Heat to boiling, remove from the
use.
heat, and allow the precipitate to settle. Filter on a coarse filter
20.2 Bias—No information on the bias of this is known
paper and wash five times with hot water. Discard the filtrate.
because at the time of the interlaboratory study, suitable
Remove the filter paper, carefully open it, and place it on the
reference materials were not available or were not tested. The
inside wall of the original 800 mL beaker. Wash the precipitate
user of this method is encouraged to employ accepted reference
from the paper using a fine stream of water. Pass 25 mL of
materials, if available, to determine the presence or absence of
HNO (1 + 1) over the paper, and wash well with water but do
bias.
not exceed a total volume of 40 mL. Discard the paper. Warm
gently until the precipitate dissolves.
LEAD BY THE DITHIZONE
18.1.5 Transfer the solution to the distillation flask, add 1 g
SPECTROPHOTOMETRIC TEST METHOD
of NH Br and 0.75 g of hydrazine sulfate. Add 20 mL of HNO
4 3
(1 + 1) to the receiving flask, and place the flask in an 800 mL
21. Scope
beaker containing cold water. Assemble the apparatus (Fig. 1),
21.1 This test method covers the determination of lead in
heat the distillation flask, and distill into the receiving flask.
chromium and ferrochromium in compositions from 0.001 %
18.1.6 Distill until the volume is reduced to 10 mL or until
to 0.05 %.
oxides of nitrogen are noted in the distillation flask. Remove
the distillation flask from the heat source. Place the receiving
22. Summary of Test Method
flask on a hot plate and evaporate the solution to dryness. Bake
22.1 After dissolution of the sample, lead is precipitated
for 30 min at 150 °C to 180 °C. Add 45 mL of ammonium
with NH OH. Interfering metals are complexed with sodium
molybdate-hydrazine sulfate solution to the flask, warm gently
citrate and sodium cyanide, and the lead dithizone complex is
to dissolve the residue, and transfer the solution to a 50 mL
extracted with chloroform. Spectrophotometric absorbance
volumetric flask. Proceed as directed in 18.3.
measurement is made at 520 nm.
18.2 Reference Solution—Carry a reagent blank through the
23. Concentration Range
entire procedure using the same amounts of all reagents with
the sample omitted. Proceed as directed in 18.3. 23.1 The recommended concentration range is from
0.001 mg to 0.025 mg of lead per 10 mL of solution, using a
18.3 Color Development—Proceed as directed in 17.3.
1 cm cell.
18.4 Spectrophotometry—Take the spectrophotometric ab-
24. Stability of Color
sorbance reading of the test solution as directed in 17.4.
24.1 The color is quite stable if the solution is protected
against evaporation and decomposition of chloroform. Because
19. Calculation
of the volatility of the solvent, it is advisable to make all
19.1 Convert the net spectrophotometric absorbance reading
readings promptly. The color develops almost immediately.
of the test solution to milligrams of arsenic by means of the
calibration curve. Calculate the percentage of arsenic as 25. Interferences
follows:
25.1 The elements ordinarily present do not interfere if their
Arsenic , % 5 A/ B × 10 (1) compositions are under the maximum limits shown in 1.1. If
~ !
E363 − 23
more than 0.005 % bismuth is present, it must be removed as 27.7 Sodium Cyanide Solution (300 g ⁄L)—Dissolve 60 g of
directed in 28.3.3 to avoid high results for lead. sodium cyanide (NaCN) in 200 mL of water. Store in a
polyethylene bottle. (Warning—The preparation, storage, use,
26. Apparatus and disposal of NaCN solutions requires special care and
attention. Avoid any possibility of inhalation, ingestion, or skin
26.1 Glassware—Use only borosilicate beakers, covers, and
contact with the compound, its solutions, or its vapors. Work
funnels. Wash all glassware with hot HNO (1 + 1) and reserve
only in a well-ventilated hood. Refer to the Hazards Section of
for this determination only. Before using separatory funnels,
Practices E50. )
rinse them with dithizone solution and then with water. Store
all reagents in glass-stoppered borosilicate bottles which have
NOTE 2—Because of the strongly alkaline properties of NaCN
solutions, contact with borosilicate glass may result in contamination of
been previously washed with hot HNO (1 + 1) and rinsed
the reagent.
with distilled water.
27.8 Sodium Sulfite Solution (Saturated)—Prepare a satu-
26.2 pH Meter—A pH meter for measurements to within
rated solution of sodium sulfite (Na SO ).
2 3
60.10 pH units is required.
27.9 Wash Solution—Add 10 mL of NH OH, 40 mL of
Na SO solution, and 20 mL of NaCN solution (Warning—
27. Reagents
2 3
See 27.7.) to 100 mL of water, and dilute to 1 L with water
27.1 Chloroform (CHCl )—(Warning—Chloroform is
(Note 2).
highly toxic and must be used in a well-ventilated hood.
Consult the Safety Data Sheet or other source of data prior to
28. Preparation of Calibration Curve
use. Refer to the Hazards Section of Practices E50.)
28.1 Calibration Solutions—Using pipets, transfer (1, 5, 10,
27.2 Dithizone Solution (0.04 g ⁄L in chloroform)—Dissolve
15, 20, and 25) mL of Standard Lead Solution (1 mL = 0.001
0.02 g of dithizone (di
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: E363 − 22 E363 − 23
Standard Test Methods for
Chemical Analysis of Chromium and Ferrochromium
This standard is issued under the fixed designation E363; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 These test methods cover the chemical analysis of chromium and ferrochromium having chemical compositions within the
following limits:
Element Composition, %
Aluminum 0.25 max
Antimony 0.005 max
Arsenic 0.005 max
Bismuth 0.005 max
Boron 0.005 max
Carbon 9.00 max
Chromium 51.0 to 75
Chromium 51.0 to 99.5
Cobalt 0.10 max
Columbium 0.05 max
Copper 0.05 max
Lead 0.005 max
Manganese 0.75 max
Molybdenum 0.05 max
Nickel 0.50 max
Nitrogen 6.00 max
Phosphorus 0.03 max
Silicon 12.00 max
Silver 0.005 max
Sulfur 0.07 max
Tantalum 0.05 max
Tin 0.005 max
Titanium 0.50 max
Vanadium 0.50 max
Zinc 0.005 max
Zirconium 0.05 max
1.2 The analytical procedures appear in the following order:
These test methods are under the jurisdiction of ASTM Committee E01 on Analytical Chemistry for Metals, Ores, and Related Materials and are the direct responsibility
of Subcommittee E01.01 on Iron, Steel, and Ferroalloys.
Current edition approved Nov. 1, 2022July 1, 2023. Published November 2022July 2023. Originally approved in 1970. Last previous edition approved in 20162022 as
E363 – 16. DOI: 10.1520/E0363-22.22. DOI: 10.1520/E0363-23.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E363 − 23
Sections
Arsenic by the Molybdenum Blue 10 – 20
Spectrophotometric Test Method
[0.001 % to 0.005 %]
Lead by the Dithizone Spectrophotometric Test 21 – 31
Method
[0.001 % to 0.05 %]
Chromium by the Sodium Peroxide Fusion- 32 – 38
Titrimetric Test Method
[50 % to 75 %]
Chromium by the Sodium Peroxide Fusion- 32 – 38
Titrimetric Test Method
[50.0 % to 99.5 %]
1.3 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this
standard.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use. Specific hazard statements are given in Section 6 and in special “Warning” paragraphs
throughout these test methods.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
A101 Specification for Ferrochromium
A481 Specification for Chromium Metal
D1193 Specification for Reagent Water
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
E32 Practices for Sampling Ferroalloys and Steel Additives for Determination of Chemical Composition
E50 Practices for Apparatus, Reagents, and Safety Considerations for Chemical Analysis of Metals, Ores, and Related Materials
E60 Practice for Analysis of Metals, Ores, and Related Materials by Spectrophotometry
E135 Terminology Relating to Analytical Chemistry for Metals, Ores, and Related Materials
E173 Practice for Conducting Interlaboratory Studies of Methods for Chemical Analysis of Metals (Withdrawn 1997)
E1601 Practice for Conducting an Interlaboratory Study to Evaluate the Performance of an Analytical Method
3. Terminology
3.1 For definition of terms used in this test method, refer to Terminology E135.
4. Significance and Use
4.1 These test methods for the chemical analysis of chromium metal and ferrochromium alloy are primarily intended to test such
materials for compliance with compositional specifications such as Specifications A101 and A481. It is assumed that all who use
these test methods will be trained analysts capable of performing common laboratory procedures skillfully and safely. It is expected
that work will be performed in a properly equipped laboratory.
5. Apparatus, Reagents, and Spectrophotometric Practice
5.1 Apparatus, standard solutions, and other reagents required for each determination are listed in separate sections preceding the
procedure. Spectrophotometers shall conform to the requirements prescribed in Practice E60. (See 5.1.1.)
5.1.1 In these methods, cells utilized to contain the reference material and sample solutions in spectrophotometers are referred to
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
The last approved version of this historical standard is referenced on www.astm.org.
E363 − 23
as “absorption cells.” The radiant energy passed through the cells can be measured as absorbance or transmittance. These methods
refer to absorbance measurements. Refer to Practice E60 for details.
5.2 Spectrophotometric practices prescribed in these test methods shall conform to Practice E60.
5.3 Purity of Water—Unless otherwise indicated, references to water shall be understood to mean reagent water conforming to
Type I or Type II of Specification D1193. Type III or Type IV may be used if they effect no measurable change in the blank or
sample.
5.4 Purity of Reagents—Reagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that all
reagents conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society where such
specifications are available. Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high purity
to permit its use without lessening the accuracy of the determination.
6. Hazards
6.1 For precautions to be observed in the use of certain reagents in these test methods, refer to Practices E50.
6.2 Specific hazard statements are given in 27.1, 27.7, and 36.2.
7. Sampling
7.1 For procedures to sample the material, and particle size requirements of the sample, refer to Practices E32.
8. Rounding Calculated Values
8.1 Rounding of test results obtained using this test method shall be performed as directed in Practice E29, Rounding Method,
unless an alternative rounding method is specified by the customer or applicable material specification.
9. Interlaboratory Studies
9.1 These test methods have been evaluated in accordance with Practice E173, unless otherwise noted in the Precision and Bias
section. Practice E173 has been replaced by Practice E1601. The Reproducibility R corresponds to the Reproducibility Index R
of Practice E1601. The Repeatability R of Practice E173 corresponds to the Repeatability Index r of Practice E1601.
ARSENIC BY THE MOLYBDENUM BLUE SPECTROPHOTOMETRIC TEST METHOD
10. Scope
10.1 This test method covers the determination of arsenic in chromium and ferrochromium in compositions from 0.001 % to
0.005 %.
10. Scope
10.1 This test method covers the determination of arsenic in chromium and ferrochromium in compositions from 0.001 % to
0.005 %.
11. Summary of Method
11.1 Arsenic is first separated by distillation as the trivalent chloride. Ammonium molybdate is added to form arsenomolybdate,
which is then reduced by hydrazine sulfate to form the molybdenum blue complex. Spectrophotometric absorbance measurement
is made at 850 nm.
Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC., www.acs.org . For suggestions on the testing of reagents
not listed by the American Chemical Society, see the United States Pharmacopeia and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD,
www.usp.org.
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FIG. 1 Arsenic Distillation Apparatus
12. Concentration Range
12.1 The recommended concentration range is 0.01 mg to 0.15 mg of arsenic per 50 mL of solution using a 1 cm cell. (See Note
1.)
NOTE 1—This test method has been written for cells having a 1 cm light path. Cells having other dimensions may be used, provided suitable adjustments
can be made in the amount of sample and reagents used.
13. Stability of Color
13.1 The color is stable for at least 2 h.
14. Interferences
14.1 The elements ordinarily present do not interfere if their compositions are under the maximum limits shown in 1.1.
15. Apparatus
15.1 Distillation Apparatus, Fig. 1.
15.2 Zirconium Crucibles, 30 mL capacity.
16. Reagents
16.1 Ammonium Bromide (NH Br).
16.2 Ammonium Molybdate Solution (10 g ⁄L)—Dissolve 2.5 g of ammonium heptamolybdate tetrahydrate ((NH ) Mo O •
4 6 7 24
4H O) in 40 mL of warm water. Add 128 mL of H SO (1(1 + 3), dilute to 250 mL, and mix.
2 2 4
16.3 Ammonium Molybdate-Hydrazine Sulfate Solution—Dilute 100 mL of ammonium molybdate solution to 900 mL, add 10 mL
of hydrazine sulfate solution, dilute to 1 L, and mix. Do not use a solution that has stood more than 1 h.
E363 − 23
16.4 Arsenic, Standard Solution A (1 mL = 0.10 mg As)—Transfer 0.1320 g of arsenic trioxide (As O ) to a 1 L volumetric flask,
2 3
dissolve in 100 mL of HCl, cool, dilute to volume, and mix.
16.5 Arsenic, Standard Solution B (1 mL = 0.01 mg As)—Using a pipet, transfer 100 mL of arsenic solution A (1 mL =
0.10 mg As) to a 1 L volumetric flask, dilute to volume, and mix.
16.6 Hydrazine Sulfate ((NH ) •H SO ).
2 2 2 4
16.7 Hydrazine Sulfate Solution (1.5 g ⁄L)—Dissolve 1.5 g of hydrazine sulfate ((NH ) •H SO ) in water, dilute to 1 L, and mix.
2 2 2 4
Do not use a solution that has stood more than 1 day.
16.8 Sodium Carbonate (Na CO ).
2 3
16.9 Sodium Peroxide (Na O ).
2 2
17. Preparation of Calibration Curve
17.1 Calibration Solutions:
17.1.1 Using pipets, transfer (1, 2, 5, 10, and 15) mL of arsenic Solution B (1 mL = 0.01 mg As) to 125 mL Erlenmeyer flasks.
17.1.2 Add 10 mL of HNO and evaporate the solution to dryness on a hot plate. Bake for 30 min at 150 °C to 180 °C. Remove
from the hot plate. Add 45 mL of ammonium molybdate-hydrazine sulfate solution to each flask, warm gently to dissolve the
residue, and transfer the solution to a 50 mL volumetric flask. Proceed as directed in 17.3.
17.2 Reference Solution—Transfer 10 mL of HNO to a 125 mL Erlenmeyer flask and proceed as directed in 17.1.2.
17.3 Color Development—Heat the flask in a boiling water bath for 15 min. Remove the flask, cool to room temperature, dilute
to volume with ammonium molybdate-hydrazine sulfate solution, and mix.
17.4 Spectrophotometry:
17.4.1 Multiple-Cell Spectrophotometer—Measure the cell correction using absorption cells with a 1 cm light path and a light band
centered at 850 nm. Using the test cell, take the spectrophotometric absorbance readings of the calibration solutions.
17.4.2 Single-Cell Spectrophotometer—Transfer a suitable portion of the reference solution to an absorption cell with a 1 cm light
path and adjust the spectrophotometer to the initial setting, using a light band centered at 850 nm. While maintaining this
adjustment, take the spectrophotometric absorbance readings of the calibration solutions.
17.5 Calibration Curve—Plot the net spectrophotometric absorbance readings of the calibration solutions against milligrams of
arsenic per 50 mL of solution. Follow the instrument manufacturer’s instructions for generating the calibration curve.
18. Procedure
18.1 Test Solution:
18.1.1 Select and weigh a sample to the nearest 0.2 mg as follows:
As, % Sample Mass, g
0.001 to 0.015 0.500
0.01 to 0.04 0.250
0.035 to 0.10 0.125
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18.1.1.1 Transfer the sample to a 30 mL zirconium crucible containing 10 g of Na O and 1 g of Na CO if ferrochromium, or
2 2 2 3
8 g of Na O plus 2 g of Na CO if chromium metal.
2 2 2 3
18.1.2 Mix thoroughly with a metal spatula. Fuse carefully over a free flame by holding the crucible with a pair of tongs and
slowly revolving it around the outer edge of the flame until the contents have completely melted; raise the temperature gradually
to avoid spattering. When the contents are molten, give the crucible a rotary motion to dissolve any undissolved particles of the
alloy adhering to the bottom or sides. Finally, increase the temperature until the crucible is bright red for 1 min. Cool the crucible
to room temperature. Transfer the crucible to an 800 mL beaker containing 60 mL of H SO (1 + 1) and 200 mL of water. Dissolve
2 4
the melt; remove and rinse the crucible.
18.1.3 If manganese dioxide is present, add H SO drop-wise until the solution clears.
2 4
18.1.4 Heat to boiling, and cool. While stirring vigorously, add NH OH until the solution is alkaline to litmus, and then add 3 mL
to 5 mL in excess. Heat to boiling, remove from the heat, and allow the precipitate to settle. Filter on a coarse filter paper and wash
five times with hot water. Discard the filtrate. Remove the filter paper, carefully open it, and place it on the inside wall of the
original 800 mL beaker. Wash the precipitate from the paper using a fine stream of water. Pass 25 mL of HNO (1 + 1) over the
paper, and wash well with water but do not exceed a total volume of 40 mL. Discard the paper. Warm gently until the precipitate
dissolves.
18.1.5 Transfer the solution to the distillation flask, add 1 g of NH Br and 0.75 g of hydrazine sulfate. Add 20 mL of HNO (1
4 3
+ 1) to the receiving flask, and place the flask in an 800 mL beaker containing cold water. Assemble the apparatus (Fig. 1), heat
the distillation flask, and distill into the receiving flask.
18.1.6 Distill until the volume is reduced to 10 mL or until oxides of nitrogen are noted in the distillation flask. Remove the
distillation flask from the heat source. Place the receiving flask on a hot plate and evaporate the solution to dryness. Bake for
30 min at 150 °C to 180 °C. Add 45 mL of ammonium molybdate-hydrazine sulfate solution to the flask, warm gently to dissolve
the residue, and transfer the solution to a 50 mL volumetric flask. Proceed as directed in 18.3.
18.2 Reference Solution—Carry a reagent blank through the entire procedure using the same amounts of all reagents with the
sample omitted. Proceed as directed in 18.3.
18.3 Color Development—Proceed as directed in 17.3.
18.4 Spectrophotometry—Take the spectrophotometric absorbance reading of the test solution as directed in 17.4.
19. Calculation
19.1 Convert the net spectrophotometric absorbance reading of the test solution to milligrams of arsenic by means of the
calibration curve. Calculate the percentage of arsenic as follows:
Arsenic ,%5 A/ B ×10 (1)
~ !
where:
A = milligrams of arsenic found in 50 mL of final test solution, and
B = grams of sample represented in 50 mL of final test solution.
A = milligrams of arsenic found in 50 mL of final test solution,
B = grams of sample represented in 50 mL of final test solution, and
10 = conversion factor from mg to percent.
20. Precision and Bias
20.1 Precision—Nine laboratories cooperated in testing this test method and obtained the data summarized in Table 1. Samples
with arsenic compositions near the upper limit of the scope were not available for testing. The user is cautioned to verify, by the
use of reference materials, if available, that the precision of this test method is adequate for the contemplated use.
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TABLE 1 Statistical Information—Arsenic
Repeatability Reproducibility
Ferroalloy Type As Found, % (R , Practice (R , Practice
1 2
E173) E173)
1. 70Cr-1Si-5C 0.0015 0.0001 0.0005
20.2 Bias—No information on the bias of this is known because at the time of the interlaboratory study, suitable reference
materials were not available or were not tested. The user of this method is encouraged to employ accepted reference materials, if
available, to determine the presence or absence of bias.
LEAD BY THE DITHIZONE SPECTROPHOTOMETRIC TEST METHOD
21. Scope
21.1 This test method covers the determination of lead in chromium and ferrochromium in compositions from 0.001 % to 0.05 %.
21. Scope
21.1 This test method covers the determination of lead in chromium and ferrochromium in compositions from 0.001 % to 0.05 %.
22. Summary of Test Method
22.1 After dissolution of the sample, lead is precipitated with NH OH. Interfering metals are complexed with sodium citrate and
sodium cyanide, and the lead dithizone complex is extracted with chloroform. Spectrophotometric absorbance measurement is
made at 520 nm.
23. Concentration Range
23.1 The recommended concentration range is from 0.001 mg to 0.025 mg of lead per 10 mL of solution, using a 1 cm cell.
24. Stability of Color
24.1 The color is quite stable if the solution is protected against evaporation and decomposition of chloroform. Because of the
volatility of the solvent, it is advisable to make all readings promptly. The color develops almost immediately.
25. Interferences
25.1 The elements ordinarily present do not interfere if their compositions are under the maximum limits shown in 1.1. If more
than 0.005 % bismuth is present, it must be removed as directed in 28.3.3 to avoid high results for lead.
26. Apparatus
26.1 Glassware—Use only borosilicate beakers, covers, and funnels. Wash all glassware with hot HNO (1 + 1) and reserve for
this determination only. Before using separatory funnels, rinse them with dithizone solution and then with water. Store all reagents
in glass-stoppered borosilicate bottles which have been previously washed with hot HNO (1 + 1) and rinsed with distilled water.
26.2 pH Meter—A pH meter for measurements to within 60.10 pH units is required.
27. Reagents
27.1 Chloroform (CHCl )—(Warning—Chloroform is highly toxic and must be used in a well-ventilated hood. Consult the Safety
Data Sheet or other source of data prior to use. Refer to the Hazards Section of Practices E50.)
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27.2 Dithizone Solution (0.04 g ⁄L in chloroform)—Dissolve 0.02 g of dithizone (diphenylthiocarbazone) in 80 mL of CHCl in
a 500 mL conical separatory funnel, add 100 mL of cold water and 10 mL of NH OH, stopper, and shake vigorously for 1 min to
2 min. Draw off the CHCl layer and discard. Wash the aqueous layer with 5 mL of CHCl and discard the latter. Add HCl (1 +
3 3
9) to the aqueous layer until it is just acidic to litmus paper, cool, and extract with three 50 mL portions of CHCl . Combine the
CHCl extracts, wash several times with water until the aqueous phase does not give an acid test with pH paper, and discard the
aqueous layer. Dilute the CHCl layer to 500 mL with CHCl and store in an amber glass bottle preferably in a refrigerator.
3 3
27.3 Hydroxylamine Hydrochloride Solution (10 g ⁄L)—Dissolve 0.5 g of hydroxylamine hydrochloride (NH OH·HCl) in 50 mL
of water. Prepare fresh as needed.
27.4 Iron Solution—Dissolve 1 g of iron (lead content 0.001 % maximum) in 10 mL of HCl (1 + 1) and 10 mL of HNO . Add
10 mL of HClO , heat to strong fumes, cool, and dilute to 100 mL.
27.5 Lead Standard Solution (1 mL = 0.001 mg Pb)—Dissolve 0.2000 g of lead (purity 99.9 % minimum) in 20 mL of HNO (1
+ 1), and heat moderately to expel oxides of nitrogen. Cool, transfer to a 1 L volumetric flask, dilute to volume, and mix. Using
a pipet, transfer 5 mL of this solution to a 1 L volumetric flask, dilute to volume, and mix.
27.6 Sodium Citrate Solution—Dissolve 30 g of sodium citrate dihydrate in 100 mL of distilled water. Add NH OH until th
...