ASTM D4628-23

Standard Test Method for Analysis of Barium, Calcium, Magnesium, and Zinc in Unused Lubricating Oils by Atomic Absorption Spectrometry

SIGNIFICANCE AND USE
5.1 Some oils are formulated with metal-containing additives that act as detergents, antioxidants, antiwear agents, etc. Some of these additives contain one or more of these metals: barium, calcium, zinc, and magnesium. This test method provides a means of determining the concentration of these metals that gives an indication of the additive content in these oils.  
5.2 Several additive metals and their compounds are added to the lubricating oils to give beneficial performance. (See Table 1.)
SCOPE
1.1 This test method is applicable for the determination of mass percent barium from 0.005 % to 1.0 %, calcium and magnesium from 0.002 % to 0.3 %, and zinc from 0.002 % to 0.2 % in lubricating oils.  
1.2 Higher concentrations can be determined by appropriate dilution. Lower concentrations of metals such as barium, calcium, magnesium, and zinc at about 10 ppm level can also be determined by this test method. Use of this test method for the determination at these lower concentrations should be by agreement between the buyer and the seller.  
1.3 Lubricating oils that contain viscosity index improvers may give low results when calibrations are performed using standards that do not contain viscosity index improvers.  
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.5 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 warning statements are given in 4.1, 7.3, and 9.1.  
1.6 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-Apr-2023
• ICS: 71.040.50 - Physicochemical methods of analysis
• ICS: 75.100 - Lubricants, industrial oils and related products
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.03 - Elemental Analysis

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: D4628 − 23
Standard Test Method for
Analysis of Barium, Calcium, Magnesium, and Zinc in
Unused Lubricating Oils by Atomic Absorption
1
Spectrometry
This standard is issued under the fixed designation D4628; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope* 2. Referenced Documents
2
2.1 ASTM Standards:
1.1 This test method is applicable for the determination of
D4175 Terminology Relating to Petroleum Products, Liquid
mass percent barium from 0.005 % to 1.0 %, calcium and
Fuels, and Lubricants
magnesium from 0.002 % to 0.3 %, and zinc from 0.002 % to
D6299 Practice for Applying Statistical Quality Assurance
0.2 % in lubricating oils.
and Control Charting Techniques to Evaluate Analytical
1.2 Higher concentrations can be determined by appropriate
Measurement System Performance
dilution. Lower concentrations of metals such as barium,
3. Terminology
calcium, magnesium, and zinc at about 10 ppm level can also
3.1 Definitions:
be determined by this test method. Use of this test method for
3.1.1 For definitions of terms used in this test method, refer
the determination at these lower concentrations should be by
to Terminology D4175.
agreement between the buyer and the seller.
4. Summary of Test Method
1.3 Lubricating oils that contain viscosity index improvers
may give low results when calibrations are performed using
4.1 A sample is weighed and base oil is added to 0.25 g 6
standards that do not contain viscosity index improvers.
0.01 g total mass. Fifty millilitres of a kerosene solution,
containing potassium as an ionization suppressant, are added,
1.4 The values stated in SI units are to be regarded as
and the sample and oil are dissolved. (Warning—Hazardous.
standard. No other units of measurement are included in this
Potentially toxic and explosive.) Standards are similarly
standard.
prepared, always adding oil if necessary to yield a total mass of
1.5 This standard does not purport to address all of the 0.25 g. These solutions are burned in the flame of an atomic
safety concerns, if any, associated with its use. It is the absorption spectrophotometer. An acetylene/nitrous oxide
flame is used. (Warning—Combustible. Vapor harmful.)
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
5. Significance and Use
mine the applicability of regulatory limitations prior to use.
5.1 Some oils are formulated with metal-containing addi-
Specific warning statements are given in 4.1, 7.3, and 9.1.
tives that act as detergents, antioxidants, antiwear agents, etc.
1.6 This international standard was developed in accor-
Some of these additives contain one or more of these metals:
dance with internationally recognized principles on standard-
barium, calcium, zinc, and magnesium. This test method
ization established in the Decision on Principles for the
provides a means of determining the concentration of these
Development of International Standards, Guides and Recom-
metals that gives an indication of the additive content in these
mendations issued by the World Trade Organization Technical
oils.
Barriers to Trade (TBT) Committee.
5.2 Several additive metals and their compounds are added
to the lubricating oils to give beneficial performance. (See
Table 1.)
1
This test method is under the jurisdiction of ASTM Committee D02 on
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of
2
Subcommittee D02.03 on Elemental Analysis. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved May 1, 2023. Published June 2023. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 1986. Last previous edition approved in 2016 as D4628 – 16. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/D4628-23. the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D4628 − 23
TABLE 1 Lubricants and Additive Materials
Element Compounds Purpose/Application
Barium Sulfonates, phenates Detergent inhibitors, corrosion inhibitors, detergents, rust
inhibitors, automatic trans
...

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: D4628 − 16 D4628 − 23
Standard Test Method for
Analysis of Barium, Calcium, Magnesium, and Zinc in
Unused Lubricating Oils by Atomic Absorption
1
Spectrometry
This standard is issued under the fixed designation D4628; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope*
1.1 This test method is applicable for the determination of mass percent barium from 0.005 % to 1.0 %, calcium and magnesium
from 0.002 % to 0.3 %, and zinc from 0.002 % to 0.2 % in lubricating oils.
1.2 Higher concentrations can be determined by appropriate dilution. Lower concentrations of metals such as barium, calcium,
magnesium, and zinc at about 10 ppm level can also be determined by this test method. Use of this test method for the
determination at these lower concentrations should be by agreement between the buyer and the seller.
1.3 Lubricating oils that contain viscosity index improvers may give low results when calibrations are performed using standards
that do not contain viscosity index improvers.
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 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 and healthsafety, health, and environmental practices and determine
the applicability of regulatory limitations prior to use. Specific warning statements are given in 3.14.1, 6.37.3, and 8.19.1.
1.6 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
2.1 ASTM Standards:
D4175 Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants
D6299 Practice for Applying Statistical Quality Assurance and Control Charting Techniques to Evaluate Analytical Measure-
ment System Performance
3. Terminology
3.1 Definitions:
1
This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of Subcommittee
D02.03 on Elemental Analysis.
Current edition approved Dec. 1, 2016May 1, 2023. Published January 2017June 2023. Originally approved in 1986. Last previous edition approved in 20142016 as
D4628 – 14.D4628 – 16. DOI: 10.1520/D4628-16.10.1520/D4628-23.
2
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.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D4628 − 23
TABLE 1 Lubricants and Additive Materials
Element Compounds Purpose/Application
Barium Sulfonates, phenates Detergent inhibitors, corrosion inhibitors, detergents, rust
inhibitors, automatic transmission fluids
Calcium Sulfonates, phenates Detergent inhibitors, dispersants
Magnesium Sulfonates, phenates Detergent inhibitors
Zinc Dialkyldithiophosphates, dithiocarbamates, Anti-oxidant, corrosion inhibitors, antiwear additives,
phenolates carboxylates detergents, crankcase oils, hypoid gear lubricants, aircraft
piston engine oils, turbine oils, automatic transmission
fluids, railroad diesel engine oils, brake lubricants
3.1.1 For definitions of terms used in this test method, refer to Terminology D4175.
4. Summary of Test Method
4.1 A sample is weighed and base oil is added to 0.25 g 6 0.01 g total mass. Fifty millilitres of a kerosene solution, containing
potassium as an ionization suppressant, are added, and the sample and oil are dissolved. (Warning—Hazardous. Potentially toxic
and explosive.) Standards are similarly prepared, always adding oil if necessary to yield a total mass of 0.25 g. These solutions
are burned in the flame of an a
...