1、Designation: D2442 75 (Reapproved 2012)Standard Specification forAlumina Ceramics for Electrical and ElectronicApplications1This standard is issued under the fixed designation D2442; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers the requirements for fabricatedalumina parts suitable for electronic and electri
3、cal applicationsand ceramic-to-metal seals as used in electron devices. Thisstandard specifies limits and methods of test for electrical,mechanical, thermal, and general properties of the bodies usedfor these fabricated parts, regardless of part geometry.1.2 The values stated in SI units are to be r
4、egarded as thestandard. The values given in parentheses are for informationonly.2. Referenced Documents2.1 ASTM Standards:2C20 Test Methods forApparent Porosity, WaterAbsorption,Apparent Specific Gravity, and Bulk Density of BurnedRefractory Brick and Shapes by Boiling WaterC108 Symbols for Heat Tra
5、nsmissionC242 Terminology of Ceramic Whitewares and RelatedProductsC408 Test Method for Thermal Conductivity of WhitewareCeramicsC573 Methods for ChemicalAnalysis of Fireclay and High-Alumina Refractories3C623 Test Method for Youngs Modulus, Shear Modulus,and Poissons Ratio for Glass and Glass-Ceram
6、ics byResonanceD116 Test Methods for Vitrified Ceramic Materials forElectrical ApplicationsD149 Test Method for Dielectric Breakdown Voltage andDielectric Strength of Solid Electrical Insulating Materialsat Commercial Power FrequenciesD150 Test Methods for AC Loss Characteristics and Per-mittivity (
7、Dielectric Constant) of Solid Electrical Insula-tionD257 Test Methods for DC Resistance or Conductance ofInsulating MaterialsD618 Practice for Conditioning Plastics for TestingD1711 Terminology Relating to Electrical InsulationD1829 Test Method for Electrical Resistance of CeramicMaterials at Elevat
8、ed Temperatures3D2149 Test Method for Permittivity (Dielectric Constant)And Dissipation Factor Of Solid Dielectrics At Frequen-cies To 10 MHz And Temperatures To 500CD2520 Test Methods for Complex Permittivity (DielectricConstant) of Solid Electrical Insulating Materials at Mi-crowave Frequencies an
9、d Temperatures to 1650C4E6 Terminology Relating to Methods of Mechanical TestingE12 Terminology Relating to Density and Specific Gravityof Solids, Liquids, and Gases3E122 Practice for Calculating Sample Size to Estimate,With Specified Precision, the Average for a Characteristicof a Lot or ProcessE16
10、5 Practice for Liquid Penetrant Examination for GeneralIndustryE228 Test Method for Linear Thermal Expansion of SolidMaterials With a Push-Rod DilatometerF19 Test Method for Tension and Vacuum Testing Metal-lized Ceramic SealsF77 Test Method for Electrical Resistance of CeramicMaterials at Elevated
11、Temperatures3F109 Terminology Relating to Surface Imperfections onCeramicsF134 Test Methods for Determining Hermeticity of Elec-tron Devices with a Helium Mass Spectrometer LeakDetector31This specification is under the jurisdiction of Committee C21 on CeramicWhitewares and Related Products and is th
12、e direct responsibility of SubcommitteeC21.03 on Methods for Whitewares and Environmental Concerns.This specification also includes material and suggestions provided by ASTMCommittee D09 on Electrical and Electronic Insulating Materials.Current edition approved April 1, 2012. Published April 2012. O
13、riginallyapproved in 1965. Last previous edition approved in 2007 as D2442 75(2007).DOI: 10.1520/D2442-75R12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the sta
14、ndards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.4Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C
15、700, West Conshohocken, PA 19428-2959, United States.F417 Test Method for Flexural Strength (Modulus of Rup-ture) of Electronic-Grade Ceramics32.2 Other Standards:MIL-STD-105 Sampling Procedures and Tables for Inspec-tion by Attributes5MIL-STD-883 Test Methods and Procedures for Microelec-tronics6AN
16、SI B46.1 Surface Texture73. Terminology3.1 Definitions:3.1.1 The applicable definitions of terms in the followingdocuments shall apply to this specification: Symbols C108, andDefinitions C242, D1711, E6, E12, and F109.4. Classification4.1 Ceramics covered by this specification shall be classi-fied b
17、y alumina content as follows:TypeAlumina ContentWeight percent, minI82II 93III 97IV 995. Basis of Purchase5.1 Purchase orders for ceramic parts furnished to thisspecification shall include the following information:5.1.1 Type designation (see 3.1),5.1.2 Surface finish and allowable defect limits (if
18、 required)(Definitions F109, ANSI B46.1, and Appendix X1),5.1.3 Part drawing with dimensional tolerances (AppendixX1),5.1.4 Specific tests (if required),5.1.5 Certification (if required), and5.1.6 Packing and marking.6. Requirements6.1 This material shall conform to the electrical, mechani-cal, ther
19、mal, and general property requirements specified inTable 1, Table 2, Table 3, and Table 4.6.2 Dimensional and surface finish requirements of the partsshall be as agreed between the supplier and the purchaser;however, guidance for establishing such an agreement isprovided in Appendix X1.6.3 Visual Re
20、quirements:6.3.1 Parts shall be uniform in color and texture. Cracks,blisters, holes, porous areas, inclusions, and adherent foreignparticles shall not be permitted. The limits of surface imper-fections such as pits, pocks, chips (open or closed), surfacemarks, fins, ridges, and flow lines shall be
21、set by mutualagreement between the supplier and the purchaser. Limitingdimensions for these defects, when required for clarification,will be listed in the parts drawing or purchase description. Fordefinitions of the surface imperfections enumerated above, seeDefinitions F109.6.3.2 For hermetic seal
22、applications at least34 of the widthof the seal surface shall remain intact at the location of anydefect.6.3.3 On other surfaces the limits for defects are such thatthe dimensional tolerances of the part are not affected at thelocation of the defect.7. Test Specimens7.1 The preferred specimens for t
23、est are, where possible, theactual part. When necessary, however, specific test specimensshall be prepared from the same batch of material and by thesame processes as those employed in fabricating the ceramicpart insofar as possible.8. Specimen Preparation8.1 The specimens for tests described in 9.1
24、-9.3 shall bepreconditioned in accordance with Procedure A of Test Meth-ods D618.9. Test Methods9.1 Dielectric Constant and Dissipation FactorDetermine in accordance with Test Methods D150. Determinevalues at higher frequencies in accordance with Test Methods5Available from the Superintendent of Doc
25、uments, Government Printing Office,Washington, D.C. 20402.6Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.7Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, htt
26、p:/www.ansi.orgTABLE 1 Electrical RequirementsProperty Type I Type II Type III Type IVDielectric constant,max 25C:at 1 MHzat 10 GHz8.88.79.69.69.89.810.110.1Dissipation factor,max 25C:at 1 MHzat 10 GHzVolume resistivity,min Vcm:0.0020.0020.0010.0010.00050.00050.00020.0002at 25C 1014101410141014at 30
27、0C 1 3 10101 3 10101 3 10107 3 1010at 500C 4 3 1072 3 1078 3 1071 3 108at 700C 4 3 1062 3 1066 3 1061 3 107at 900C 4 3 1052 3 1058 3 1051 3 106Dielectricstrength:3.175 mm(0.125 in.)min kV/mm9.85(250 V/mil)9.85(250 V/mil)9.85(250 V/mil)9.85(250 V/mil)TABLE 2 Mechanical RequirementsProperty Type I Typ
28、e II Type III Type IVFlexural strength,min avg,AMPa (psi)240(35 000)275(40 000)275(40 000)275(40 000)Modulus ofelasticity, min,GPa (psi)215(31 3 106)275(40 3 106)310(45 3 106)345(50 3 106)Poissons ratio,average0.20 to 0.25 0.20 to 0.25 0.20 to 0.25 0.20 to 0.25AMaximum permissible coefficient of var
29、iation is 10 percent.D2442 75 (2012)2D2520.8Determine values at higher temperatures in accor-dance with Test Method D2149.9.2 Volume ResistivityDetermine in accordance with TestMethods D257. For elevated temperature measurements useProcedure A of Test Method D1829.9.3 Dielectric StrengthRun this tes
30、t under oil in accor-dance with 6.1.1 ofTest Methods D149, with a rise rate of 1000V/s on a 3.175-mm (0.125-in.) thick test specimen.9.4 Flexural StrengthDetermine in accordance with TestMethod F417 or Methods D116. Somewhat lower values willresult if Methods D116 are used. The method to be used sha
31、llbe agreed upon between the supplier and the purchaser.9.5 Modulus of Elasticity and Poissons RatioDeterminein accordance with Test Method C623.9.6 Thermal ExpansionDetermine in accordance withTest Method E228.9.7 Thermal ConductivityDetermine in accordance withTest Method C408. For temperatures in
32、 excess of 149 C (300F), use a suitable method.99.8 Thermal Shock ResistanceThis test is to be agreedupon between supplier and purchaser. It is suggested that thecold end of the cycle be ice water at 0C. Methods of heatingand conditions at elevated temperatures shall be negotiated.The transfer from
33、one temperature extreme to another shall beimmediate.9.9 Temperature DeformationDetermine deformation at1500C in accordance with Appendix X2.9.10 Apparent DensityDetermine in accordance with TestMethod F77. For large ceramic parts not covered by thismethod, determine in accordance with Test Methods
34、C20.9.11 Compositional AnalysisUse either quantitative emis-sion spectrographic analysis of the fired ceramic with aluminacontent determined by difference or Methods C573 afterassuming that all determined metallic and reactive elementsoriginally are present as their highest form of oxide.9.12 Gas Im
35、permeabilityWhen air fired at 900C for 30min and handled with tweezers only, then tested on a heliummass spectrometer leak detector capable of detecting a leak of109atmcm3/s, the ceramic is considered impermeable if aspecimen 0.254 mm (0.010 in.) thick shows no indication ofhelium leakage when an ar
36、ea of 322.6 mm2(0.5 in.2) is testedfor 15 s at room temperature (Method 1014, Seal, of MIL-STD-883 and Test Methods F134).9.13 Liquid ImpermeabilityDetermine in accordance withMethods D116.9.14 Surface ImperfectionsExamine visually for surfaceimperfections with or without the aid of a dye penetrant
37、as inPractice E165. Agreement by purchaser and supplier regardingspecific techniques is strongly recommended.9.15 Surface FinishIf surface finish is specified, it shallbe determined by any appropriate method agreed upon bypurchaser and supplier.10. Inspection10.1 When agreed upon between the manufac
38、turer and thepurchaser, the purchaser may inspect the ceramic parts and8For another suitable method see Dielectric Materials and Applications, editedby Von Hippel, A., John Wiley and Sons, Inc., New York, N.Y., 1954.9For a suitable method see Francl, J., and Kingery, W. D., “An Apparatus forDetermin
39、ing Conductivity by a Comparative Method,” Journal of the AmericanCeramic Society, JACTA Vol 37, 1954, p. 80.TABLE 3 Thermal RequirementsPropertyType I Type II Type III Type IVmin max min max min max min maxMean coefficient of linear thermalexpansion, m/mC:25200C 5.4 6.2 5.2 6.7 5.2 6.5 5.5 6.725500
40、C 6.5 7.0 6.6 7.4 6.7 7.5 6.8 7.625800C 7.0 7.7 7.3 8.1 7.4 8.1 7.3 8.1251000C 7.4 8.2 7.5 8.3 7.6 8.3 7.5 8.4Thermal conductivity, cal/scmC:at 100C 0.023 0.049 0.031 0.077 0.048 0.073 0.052 0.090at 400C 0.015 0.022 0.014 0.036 0.022 0.033 0.023 0.047at 800C 0.009 0.018 0.009 0.021 0.014 0.021 0.014
41、 0.025Thermal shock resistance pass pass pass passMaximal deformation at 1500C . . 0.51 mm(0.02 in.)0.51 mm(0.02 in.)TABLE 4 General RequirementsAPropertyTypeI II III IVDensity, apparent minBg/cm33.37 3.57 3.72 3.78Composition, minweight percent82 93 97 99Gas Impermeability gas tightLiquid Impermeab
42、ility passMetallizabilityACAVendors shall, upon request, provide information on these properties as wellas a visual standard of a typical microstructure of their specific ceramic bodydepicting its grain size and pore volume. Changes in microstructure of the ceramicare not acceptable as they can affe
43、ct the behavior of the ceramic toward ametallizing process.BThe apparent density of a ceramic body is a function of the amount and thedensity of the primary Al2O3phase and the secondary phase plus the amount ofpores inherent to that body. The acceptable density limits for a specific aluminabody must
44、 be consistent with the composition and the pore volume of the ceramicsupplied by supplier and shall be agreed upon between the purchaser and thesupplier. Variation in the apparent density of a specific ceramic body shall be within61 percent of the nominal value.CGenerally, very high alumina content
45、 results in increased difficulty of metalliz-ing; however, variations in metallizing compositions and techniques can produceexcellent seals in all four types of alumina ceramics. Because of a wide variationin materials and techniques, no specific test is recommended. A referee test forseal strength
46、is Method F19.D2442 75 (2012)3verify the test results at the manufacturers facility. Otherwisethe purchaser shall inspect and test the ceramic parts within onemonth of the date of receipt by the purchaser or at such othertimes as may be agreed upon between the purchaser and themanufacturer.10.2 When
47、 agreed upon between the manufacturer and thepurchaser, the manufacturer shall supply, prior to fabrication,duplicate test specimens to the purchaser for his testingpurposes. These specimens shall be identical with those testedby the manufacturer, insofar as it is possible.11. Lot Acceptance Procedu
48、re11.1 Unless otherwise specified Practice E122 shall be used.When so specified, appropriate sample sizes shall be selectedfrom each lot according to MIL-STD-105. Each quality char-acteristic shall be assigned an AQL value in accordance withMIL-STD-105 definition for critical, major, and minor class
49、i-fications. Inspection levels shall be agreed upon between thesupplier and the purchaser.12. Certification12.1 Any test results requiring certification shall be explic-itly agreed upon, in writing, between the purchaser and themanufacturer.13. Packing and Marking13.1 Special packing techniques shall be subject to agree-ment between the purchaser and the manufacturer. Otherwiseall parts shall be handled, inspected, and packed in such amanner as to avoid chipping, scratches, and contamination, andin accordance with the best pra
