ASTM B665-03

Standard Guide for Metallographic Sample Preparation of Cemented Tungsten Carbides

SIGNIFICANCE AND USE
This sample preparation procedure may be used to prepare metallographic samples for Test Method B 657 and Practice B 390. It does not include all variations of sample preparation.
SCOPE
1.1 This guide prescribes a method for preparing cemented carbides for metallographic examination.
1.2 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 health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 09-Apr-2003
• ICS: 77.160 - Powder metallurgy
• Technical Committee: B09 - Metal Powders and Metal Powder Products
• Drafting Committee: B09.06 - Cemented Carbides

Relations

• Replaces: ASTM B665-92(1997) - Standard Practice for Metallographic Sample Preparation of Cemented Tungsten Carbides
• Effective Date: 10-Apr-2003
• Replaced By: ASTM B665-08 - Standard Guide for Metallographic Sample Preparation of Cemented Tungsten Carbides
• Effective Date: 01-Nov-2008
• Referred By: ASTM B930-03(2021) - Standard Test Method for Rating Grain Size and Frequency of Abnormally Large Grains in Cemented Tungsten Carbides (Hardmetals)
• Effective Date: 10-Apr-2003
• Referred By: ASTM B276-21 - Standard Test Method for Apparent Porosity in Cemented Carbides
• Effective Date: 10-Apr-2003
• Referred By: ASTM B657-23 - Standard Guide for Metallographic Identification of Microstructure in Cemented Carbides
• Effective Date: 10-Apr-2003

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:B665–03
Standard Guide for
Metallographic Sample Preparation of Cemented Tungsten
1
Carbides
This standard is issued under the fixed designation B 665; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope nation. Basically, they all use diamond wheels for grinding and
diamond powders for lapping. The grinding practices differ, to
1.1 This guide prescribes a method for preparing cemented
a minor degree, with respect to grit size of diamond. In all
carbides for metallographic examination.
practices, however, the final polish is produced by extremely
1.2 This standard does not purport to address all of the
fine diamond powder lapping, and in all practices care must be
safety concerns, if any, associated with its use. It is the
exercised to retain the microstructure in its true form and to
responsibility of the user of this standard to establish appro-
avoid pull-out of the softer matrix material (usually cobalt).
priate safety and health practices and determine the applica-
While it is accepted that other procedures may be used
bility of regulatory limitations prior to use.
successfully, this procedure has proved satisfactory in many
2. Referenced Documents laboratories.
5.1.1 Mounting—Where possible, specimens should be
2.1 ASTM Standards:
mounted in a plastic material such as phenol-formaldehyde or
B 390 Practice for Evaluating Apparent Grain Size and
2
poly(methyl methacrylate) to facilitate polishing without
Distribution of Cemented Tungsten Carbides
rounding the edges. Larger specimens may be polished without
B 657 Test Method for Metallographic Determination of
2
mounting. When specimens are too large they may be sec-
Microstructure in Cemented Tungsten Carbides
tioned using a diamond cut-off wheel or they may be fractured
3. Significance and Use
(appropriate safety precautions should be used when fracturing
specimens). The area selected for examination should repre-
3.1 This sample preparation procedure may be used to
sent, as nearly as possible, the entire cross section.
prepare metallographic samples for Test Method B 657 and
5.1.2 Rough Grinding—The surface to be examined may be
Practice B 390. It does not include all variations of sample
ground flat on a surface grinder with a resin-bonded diamond
preparation.
wheel (100 to 220 grit) operated at 5000 to 5500 surface feet
4. Selection of Specimen
per minute (25 to 28 m/s). After the surface is flat, several
clean-up passes are required; the maximum depth of cut should
4.1 Cemented tungsten carbides are very often in the form
be 0.0005 in. (13 µm) per pass and copious amounts of coolant
of relatively small pieces; it is possible to select and mount the
should be used.
entire piece in such manner as to permit examination of the
5.1.3 Polishing—Polishing in three steps using diamond
entire cross section. When pieces are too large for this,
powder or paste on a synthetic short-napped cloth (the reverse
however, they should be sectioned, using a diamond cutoff
side of photographic paper, or manila file folders may also be
wheel, to allow viewing as much of a represe
...