ASTM C1336-96(2002)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:C 1336–96 (Reapproved 2002)
Standard Practice for
Fabricating Non-Oxide Ceramic Reference Specimens
Containing Seeded Inclusions
This standard is issued under the fixed designation C 1336; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 4. Significance and Use
1.1 This practice covers a procedure for fabricating both 4.1 This practice describes a method of fabrication of
green and sintered test samples of silicon carbide and silicon known discontinuities in a ceramic specimen. Such specimens
nitride containing inclusions. These samples can be used to are needed and used in nondestructive examination to demon-
determine the sensitivity and detection capability of a nonde- strate sensitivity and resolution and to assist in establishing
structive examination (NDE) method. proper examination parameters.
1.2 The values stated in SI units are to be regarded as the
5. Apparatus
standard. The values given in parentheses are for information
5.1 Aerosol Duster, moisture-free.
only.
1.3 This standard does not purport to address all of the 5.2 Die, capable of exerting pressure up to 120 MPa and
will not contaminate the compacted material.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro- 5.3 Optical Magnifier, capable of providing 10 to 303
magnification.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use. 5.4 Tubing, latex, thin-wall, for encapsulating compact dur-
ing isopressing.
2. Referenced Documents
5.5 Carver Press, or similar type of apparatus capable of
2.1 ASTM Standards: exerting the necessary pressure to consolidate the sample.
B331 Test Method for Compressibility of Metal Powders 5.6 Cold Isostatic Press, capable of maintaining 500 MPa.
Uniaxial Compaction 5.7 Oven or Furnace, which can maintain a temperature of
C373 Test Method for Water Absorption, Bulk Density, 500°C.
Apparent Porosity, andApparent Specific Gravity of Fired 5.8 Imaging Equipment, with the capability of producing a
Whiteware Products hard copy output of the image (that is, 35 mm camera, charge
coupled device (CCD) camera outputted to a video printer, a
3. Terminology
stereo microscope with 4 by 5 instamatic film, etc.).
3.1 Definitions of Terms Specific to This Standard:
5.9 Sintering Furnaces,capableofreachingtemperaturesof
3.1.1 green specimen—formed ceramic specimens as origi- 1400to2200°C.Dependingontheceramicsystemchosen,the
nally compacted prior to high-temperature densification.
furnace may be required to operate in a vacuum or under inert
3.1.2 inclusion—a solid discontinuity in a specimen, with a gas atmospheres, or both, at pressures as high as 200 MPa.
composition not that of the specimen.
5.10 Mettler Scale, or similar device capable of measuring
3.1.3 seeded inclusions—discontinuities intentionally within 0.01 mg. Measuring densities according toArchimedes
placed at prescribed locations in reference specimens.
principle requires the use of a sample holder suspended in
3.1.4 sintered specimen—formed ceramic specimen after water attached to the scale.
firing to densify and remove solvents or binders.
6. Materials
6.1 Silicon Carbide or Silicon Nitride Powders, of appro-
This practice is under the jurisdiction ofASTM Committee C28 onAdvanced
priate purity and particle size, prepared with sintering aids and
Ceramics and is the direct responsibility of Subcommittee C28.03 on Physical
binder representative of the product to be inspected and in a
Properties and Non-Destructive Evaluation.
Current edition approved May 10, 2002. Published August 1996. Originally
mannerappropriatefordrypressingwithgranulesizelessthan
published as C1336 – 96. Last previous edition C1336 – 96.
−100 mesh.
Annual Book of ASTM Standards, Vol 02.05.
Annual Book of ASTM Standards, Vol 15.02.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
C 1336–96 (2002)
6.2 Inclusion Spheres, diameters as needed. Inclusion ma- 7.1.2.7 After final pressing, remove the specimen from the
terials selected based on applicable green and sintered inclu- die and place into thin-wall latex tubing, evacuate the air, and
sion that is desired to be investigated for a specific silicon seal the end. Cold isopress at 420 MPa or a pressure most
nitride or silicon carbide application. suitable for specific material.
7.1.2.8 Remove the specimen from the tubing and heat to a
6.2.1 The size, shape, and composition of the inclusions
shall be determined a priori before seeding. The inclusion sufficient temperature to decompose the binder if it has been
added for powder compaction assistance.
particles must be carefully selected based on the ceramic
system of interest and the purpose of the test samples. 7.1.2.9 Markthespecimenorientationwithascribemarkor
by beveling a corner or edge. Remove extraneous particles
6.2.1.1 Samples fabricated to determine the sensitivity and
from all surfaces with an aerosol duster or brush (adherent
resolution of the NDE test method should have inclusions that
particles may require light sanding).
represent the type that would be encountered in actual appli-
7.1.2.10 Measure bulk density of the specimen from direct
cations. The selection of the inclusion type should reflect the
volume and weight measurements.
possible impurities that are commonly seen after processing
7.2 For Sintered Specimens:
and that are present in the raw material.
7.2.1 Procedure:
6.2.1.2 Test samples being fabricated for NDE calibration
7.2.1.1 Follow steps in 7.1.2 to produce green specimens.
standards may require the use of inclusion particles with
7.2.1.2 Sinter green samples under suitable conditions to
well-defined properties (that is, geometry, density, modulus,
achieve full densification. Nominal sintering conditions for
composition, etc.). Such particles may be chosen to be excep-
silicon nitride are: 1700 to 1900°C for1hinan inert
tionally stable during sample fabrication.
atmosphere at 0 to 200 MPa; for silicon carbide, sintering
temperatures of 2000 to 2200°C for 0.5 h under vacuum are
7. Fabrication of Internal Seeded Inclusions
commonly used. The sintering aids used will dictate the firing
7.1 For Green Specimens:
conditions. Measure bulk density using a method referenced in
7.1.1 The test piece geometry must be appropriate for the
2.1 (Test Methods B331 and C373) or from volume and
size and geometry limits of the NDE test method. If the
weight measurements.
purpose of the test is to determine if the NDE method is
7.3 Sintered Inclusio
...