ASTM F356-75(1996)

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
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Designation: F 356 – 75 (Reapproved 1996)
Standard Specification for
Beryllia Ceramics for Electronic and Electrical Applications
This standard is issued under the fixed designation F 356; 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 at Commercial Power Frequencies
D 150 Test Methods for A-C Loss Characteristics and
1.1 This specification covers fabricated beryllia parts suit-
Permittivity (Dielectric Constant) of Solid Electrical Insu-
able for electronic and electrical applications. This standard
6 ,7
lating Materials
specifies limits and methods of test for electrical, mechanical,
D 257 Test Methods for D-C Resistance or Conductance of
thermal, and general properties of the bodies used for these
Insulating Materials
fabricated parts, regardless of geometry.
D 618 Practice for Conditioning Plastics and Electrical
1.2 The values stated in inch-pound units are to be regarded
Insulating Materials for Testing
as the standard. The values in parentheses are provided for
D 1711 Terminology Relating to Electrical Insulation
information only.
D 1829 Test Method for Electrical Resistance of Ceramic
2. Referenced Documents Materials at Elevated Temperatures
D 2149 Test Method for Permittivity (Dielectric Constant)
2.1 ASTM Standards:
and Dissipation Factor of Solid Ceramic Dielectrics at
C 20 Test Methods for Apparent Porosity, Water Absorp-
Frequencies to 10 MHz and Temperatures to 500°C
tion, Apparent Specific Gravity, and Bulk Density of
D 2520 Test Methods for Complex Permittivity (Dielectric
Burned Refractory Brick and Shapes by Boiling Water
Constant) of Solid Electrical Insulating Materials at Mi-
C 108 Symbols for Heat Transmission
crowave Frequencies and Temperatures to 1650°C
C 242 Terminology of Ceramic Whitewares and Related
E 6 Terminology Relating to Methods of Mechanical Test-
Products.
ing
C 351 Test Method for Mean Specific Heat of Thermal
E 12 Terminology Relating to Density and Specific Gravity
Insulation
of Solids, Liquids, and Gases
C 408 Test Method for Thermal Conductivity of Whiteware
E 122 Practice for Choice of Sample Size to Estimate a
Ceramics
Measure of Quality for a Lot or Process
C 573 Methods for Chemical Analysis of Fireclay and
E 165 Practice for Liquid Penetrant Inspection Method
High-Alumina Refractories
E 228 Test Method for Linear Thermal Expansion of Solid
C 623 Test Method for Young’s Modulus, Shear Modulus,
Materials with a Vitreous Silica Dilatometer
and Poisson’s Ratio for Glass and Glass-Ceramics by
F 19 Test Method for Tension and Vacuum Testing Metal-
Resonance
ized Ceramic Seals
C 773 Test Method for Compressive (Crushing) Strength of
F 77 Test Method for Apparent Density of Ceramics for
Fired Whiteware Materials
Electron Device and Semiconductor Application
D 116 Methods of Testing Vitrified Ceramic Materials for
F 109 Terminology Relating to Surface Imperfections on
Electrical Applications
Ceramics
D 149 Test Methods for Dielectric Breakdown Voltage and
F 134 Test Methods for Determining Hermeticity of Elec-
Dielectric Strength of Solid Electrical Insulating Materials
tron Devices with a Helium Mass Spectrometer Leak
Detector
This specification is under the jurisdiction of Committee C-21 on Ceramic
Whitewares and Related Products and is the direct responsibility of Subcommittee
C21.03 on Fundamental Properties.
Current edition approved June 30, 1975. Published August 1975. Originally Annual Book of ASTM Standards, Vol 10.02.
published as F356 – 72 T. Last previous edition F356 – 72 T. Annual Book of ASTM Standards, Vols 08.01 and 10.01.
2 9
Annual Book of ASTM Standards, Vol 15.01. Annual Book of ASTM Standards, Vol 03.01.
3 10
Annual Book of ASTM Standards, Vol 15.02. Annual Book of ASTM Standards, Vol 15.05.
4 11
Annual Book of ASTM Standards, Vol 04.06 Annual Book of ASTM Standards, Vol 14.02.
5 12
Annual Book of ASTM Standards, Vol 03.05. Annual Book of ASTM Standards, Vol 03.03.
6 13
Annual Book of ASTM Standards, Vol 10.01. Annual Book of ASTM Standards, Vol 10.04.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
F 356
F 417 Test Method for Flexural Strength (Modulus of Rup- 5.1.6 Packaging and marking.
ture) of Electronic-Grade Ceramics
NOTE 2—Toxicity of Beryllia—In working with beryllia ceramics,
2.2 Military Standards:
personnel should avoid exposure to dust or fume producing operations
MIL-STD-105 Sampling Procedures and Tables for Inspec-
such as sawing, grinding, drilling, or processing moist atmospheres at
tion of Attributes
temperatures in excess of 1200°C. Specialized equipment is necessary to
MIL-STD-883 Test Methods and Procedures for Microelec- prevent the dispersal of dust and fumes into the air.
tronics
6. Requirements
2.3 American National Standard:
ANSI B46.1 Surface Texture
6.1 This material shall conform to the electrical, mechani-
cal, thermal, and general property requirements specified in
3. Terminology
Table 1, Table 2, Table 3, and Table 4.
3.1 Definitions:
6.2 Dimensional and surface finish requirements of the parts
3.1.1 The definitions of terms found in the following ASTM
shall be as agreed between manufacturer and purchaser;
standards apply to this specification: Symbols C108 and
however, guidance for establishing such agreement is provided
Definitions C 242, D 1711, E 6, E 12, and F 109.
in Appendix X1.
6.3 Visual Requirements:
4. Classification
6.3.1 Parts shall be uniform in color and texture. Cracks,
4.1 Ceramics covered by this specification shall be classi-
blisters, holes, porous areas, inclusions, adherent foreign par-
fied by beryllia content as follows:
ticles and surface imperfections, such as pits, pocks, chips
Beryllia Content, Weight
(open and closed), surface marks, fins, ridges, and flow lines
Type Percent Minimum
shall be limited by mutual agreement between the manufac-
I95
turer and purchaser. Limiting dimensions for these defects,
II 98
III 99
when required for clarification, will be listed in the parts
drawing or purchase description. For definitions of the surface
NOTE 1—Beryllia content alone does not control physical and electrical
properties. Both purchaser and manufacturer must be in accord where imperfections enumerated above, see Definitions F 109.
stricter control of additives is required as additives affect the chemical 3
6.3.2 For hermetic seal applications at least ⁄4 of the width
resistance, thermal, mechanical, and electrical properties as well as
of the seal surface shall remain intact at the location of any
microstructure.
defect.
6.3.3 On other surfaces the limits for defects are such that
5. Ordering Information
the dimensional tolerances of the part are not affected at the
5.1 Purchase orders for ceramic parts furnished to this
location of the defect.
specification shall include the following information:
5.1.1 Type designation (see 3.1),
7. Test Specimens
5.1.2 Surface finish and allowable defect limits, if required
7.1 The preferred specimens for test are, where possible, the
(Definitions F 109, ANSI B46.1, and Appendix X1),
actual part. When necessary, however, specific test specimens
5.1.3 Part drawing with dimensional tolerances (Appendix
shall be prepared from the same batch of material and by the
X1),
same processes as those employed in fabricating the ceramic
5.1.4 Specific tests (if required),
part insofar as possible.
5.1.5 Certification (if required), and
8. Specimen Preparation
Available from Standardization Documents, Order Desk, Bldg. 4 Section D,
8.1 The specimens for tests described in 9.1-9.3 shall be
700 Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.
preconditioned in accordance with Procedure A of Methods
Available from American National Standards Institute, 11 W. 42nd St., 13th
D 618, unless otherwise specified.
Floor, New York, NY 10036.
TABLE 1 Electrical Requirements
Property Type I Type II Type III
Dielectric constant, max 25°C:
at 1 MHz 7.0 7.0 7.0
at 10 GHz 6.8 6.8 6.9
Dissipation factor, max 25°C:
at 1 MHz 0.0005 0.0005 0.0004
at 10 GHz 0.001 0.001 0.001
Volume resistivity, min,V· cm:
14 15 15
at 25°C 10 10 10
11 12 12
at 300°C 10 10 10
10 11 11
at 500°C 10 10 10
8 9 9
at 700°C 10 10 10
6 8 8
at 900°C 10 10 10
T Value, °C (°F) 1100 (2012) 1200 (2192) 1250 (2282)
e
Dielectric strength, min, 3.18 mm (0.125 in.) kV/mm (V/mil) 11.9 (300) 11.9 (300) 11.9 (300)
F 356
TABLE 2 Mechanical Requirements
Property Type I Type II Type III
AB
Flexural strength, min, avg MPa (ksi) 138 (20) 166 (24) 186 (25)
Compressive strength, min, avg MPa (ksi) 1380 (200) 1520 (222) 1660 (240)
4 4 4
Modulus of elasticity, min, MPa (ksi) 30.4 3 10 31.4 3 10 33.3 3 10
3 3 3
(44 3 10 ) (45 3 10 ) (49 3 10 )
Poisson’s ratio, typical 0.27 0.27 0.27
A
Maximum permissible coefficient of variation is 10 percent.
B
1 MPa = 0.145 ksi.
TABLE 3 Thermal Requirements
Type I Type II Type III
Property
min max min max min max
Mean coefficient of linear thermal expansion μm/m·°C:
25 to 1000°C 9.0 10.0 8.7 9.4 8.7 9.4
Thermal conductivity (min) cal/cm·s·°C:
at 25°C 0.35 0.52 0.60
at 100°C 0.30 0.40 0.41
at 400°C 0.14 0.15 0.15
at 800°C 0.05 0.05 0.06
Specific heat (100°C) cal/g·°C (Typical) 0.30 0.30 0.31
Thermal shock resistance pass pass pass
A
TABLE 4 General Requirements
specimens may be employed such as Methods D 116, although
Property Type I Type II Type III somewhat lower values will result.
B 3
9.5 Modulus of Elasticity and Poisson’s Ratio—Determine
Density, apparent, min, g/cm 2.80 2.80 2.85
Gas impermeability gas tight
in accordance with Test Method C 623.
Liquid impermeability pass
9.6 Therm
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