ASTM C1336-96(2008)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: C1336 − 96(Reapproved 2008)
Standard Practice for
Fabricating Non-Oxide Ceramic Reference Specimens
Containing Seeded Inclusions
This standard is issued under the fixed designation C1336; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3.1.4 sintered specimen—formed ceramic specimen after
firing to densify and remove solvents or binders.
1.1 This practice covers a procedure for fabricating both
green and sintered test samples of silicon carbide and silicon
4. Significance and Use
nitride containing inclusions. These samples can be used to
4.1 This practice describes a method of fabrication of
determine the sensitivity and detection capability of a nonde-
known discontinuities in a ceramic specimen. Such specimens
structive examination (NDE) method.
are needed and used in nondestructive examination to demon-
1.2 The values stated in SI units are to be regarded as
strate sensitivity and resolution and to assist in establishing
standard. No other units of measurement are included in this
proper examination parameters.
standard.
1.3 This standard does not purport to address all of the
5. Apparatus
safety concerns, if any, associated with its use. It is the
5.1 Aerosol Duster, moisture-free.
responsibility of the user of this standard to establish appro-
5.2 Die, capable of exerting pressure up to 120 MPa and
priate safety and health practices and determine the applica-
will not contaminate the compacted material.
bility of regulatory limitations prior to use.
5.3 Optical Magnifier, capable of providing 10 to 30×
2. Referenced Documents
magnification.
2.1 ASTM Standards:
5.4 Tubing, latex, thin-wall, for encapsulating compact dur-
B331Test Method for Compressibility of Metal Powders in
ing isopressing.
Uniaxial Compaction
5.5 Carver Press, or similar type of apparatus capable of
C373Test Method for Water Absorption, Bulk Density,
exerting the necessary pressure to consolidate the sample.
ApparentPorosity,andApparentSpecificGravityofFired
Whiteware Products
5.6 Cold Isostatic Press, capable of maintaining 500 MPa.
5.7 Oven or Furnace, which can maintain a temperature of
3. Terminology
500°C.
3.1 Definitions of Terms Specific to This Standard:
5.8 Imaging Equipment, with the capability of producing a
3.1.1 green specimen—formed ceramic specimens as origi-
hard copy output of the image (that is, 35 mm camera, charge
nally compacted prior to high-temperature densification.
coupled device (CCD) camera outputted to a video printer, a
3.1.2 inclusion—a solid discontinuity in a specimen, with a
stereo microscope with 4 by 5 instamatic film, etc.).
composition not that of the specimen.
5.9 Sintering Furnaces,capableofreachingtemperaturesof
3.1.3 seeded inclusions—discontinuities intentionally
1400 to 2200°C. Depending on the ceramic system chosen, the
placed at prescribed locations in reference specimens.
furnace may be required to operate in a vacuum or under inert
gas atmospheres, or both, at pressures as high as 200 MPa.
1 5.10 Mettler Scale, or similar device capable of measuring
This practice is under the jurisdiction ofASTM Committee C28 on Advanced
Ceramics and is the direct responsibility of Subcommittee C28.03 on Physical within 0.01 mg. Measuring densities according toArchimedes
Properties and Non- Destructive Evaluation.
principle requires the use of a sample holder suspended in
Current edition approved Aug. 1, 2008. Published September 2008. Originally
water attached to the scale.
approved in 1996. Last previous edition approved in 2002 as C1336 – 96 (2002).
DOI: 10.1520/C1336-96R08.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or 6. Materials
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
6.1 Silicon Carbide or Silicon Nitride Powders, of appro-
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. priate purity and particle size, prepared with sintering aids and
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1336 − 96 (2008)
binder representative of the product to be inspected and in a compact (nominally 120 MPa); otherwise press at 60 MPa and
mannerappropriatefordrypressingwithgranulesizelessthan repeat 7.1.2.2-7.1.2.5 through until the desired number of
−100 mesh.
inclusion layers are obtained.
7.1.2.7 After final pressing, remove the specimen from the
6.2 Inclusion Spheres, diameters as needed. Inclusion ma-
die and place into thin-wall latex tubing, evacuate the air, and
terials selected based on applicable green and sintered inclu-
seal the end. Cold isopress at 420 MPa or a pressure most
sion that is desired to be investigated for a specific silicon
suitable for specific material.
nitride or silicon carbide application.
6.2.1 The size, shape, and composition of the inclusions
7.1.2.8 Remove the specimen from the tubing and heat to a
shall be determined a priori before seeding. The inclusion
sufficient temperature to decompose the binder if it has been
particles must be carefully selected based on the ceramic
added for powder compaction assistance.
system of interest and the purpose of the test samples.
7.1.2.9 Markthespecimenorientationwithascribemarkor
6.2.1.1 Samples fabricated to determine the sensitivity and
by beveling a corner or edge. Remove extraneous particles
resolution of the NDE test method should have inclusions that
from all surfaces with an aerosol duster or brush (adherent
represent the type that would be encountered in actual appli-
particles may require light sanding).
cations. The selection of the inclusion type should reflect the
7.1.2.10 Measure bulk density of the specimen from direct
possible impurities that are commonly seen after processing
volume and weight measurements.
and that are present in the raw material.
6.2.1.2 Test samples being fabricated for NDE calibration 7.2 For Sintered Specimens:
standards may require the use of inclusion particles with
7.2.1 Procedure:
well-defined properties (that is, geometry, density, modulus,
7.2.1.1 Follow steps in 7.1.2 to produce green specimens.
composition, etc.). Such particles may be chosen to be excep-
7.2.1.2 Sinter green samples under suitable conditions to
tionally stable during sample fabrication.
achieve full densification. Nominal sintering conditions for
silicon nitride are: 1700 to 1900°C for1hinan inert
7. Fabrication of Internal Seeded Inclusions
atmosphere at 0 to 200 MPa; for silicon carbide, sintering
7.1 For Green Specimens:
temperatures of 2000 to 2200°C for 0.5 h under vacuum are
7.1.1 The test piece geometry must be appropriate for the
commonly used. The sintering aids used will dictate the firing
size and geometry limits of the NDE test method. If the
conditions. Measure bul
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