1、 ENGINEERING MATERIAL SPECIFICATIONMaterial Name Specification NumberDate Action Changes1995 06 23 Activated L. MeralaWP 3948-a Page 1 of 3 THERMAL CONDUCTOR, SILICONE RUBBER COATED ALUMINUM FOIL, WSS-M99G170-AADHESIVE COATED, ONE SIDE1. SCOPEThe mate rial defined by this specification is an aluminu
2、m foil substratecoa ted on both sides with graphite loaded silicone rubber coating andadhesive coating on one side. This material is used as a thermal conductorwhere electrical insulation is not required.2. APPLICATIONThis s pecification was released originally for material used as a thermalco nduct
3、or between the amplifier or voltage regulator integrated circuitsand the heat sink in an audio module. The pad is to rep lace thermal greasewhich contaminates the electronic components.3. REQUIREMENTSAll t ests are conducted with adhesive coated material unless otherwisespecified on the engineering
4、drawing.3.1 QUALITY SYSTEM REQUIREMENTSMaterial suppliers and part producers must conform to Quality SystemRequirements, QS-9000. Material specification r equirements are to beused fo r initial qualification of materials. A Control Plan forong oing production verification is required. This plan must
5、 bereviewed and approved b y the relevant Ford Materials activity and/orFor d Supplier Technical Assistance (STA) prior to production partssubmission. Appropriate statistical tools must be used to analyzepr ocess/product data and assure consistent processing of thematerials.Part producers using this
6、 material in their products, must use Fordapproved materials and must conform to a process control plan whichhas been approved by STA and/or the relevant Materials Activity.3.2 INFRARED SPECTROPHOTOMETRY AND/OR THERMAL ANALYSISFord Motor Company, at its option, may conduct infrared and/ortherma l an
7、alysis of material/parts supplied to this specification.The IR spectra and thermograms established for i nitial approval shallconst itute the reference standard and shall be kept on file at thedesignated material laboratory. All samples sha ll produce IR spectraand thermograms that correspond to the
8、 reference standard when testedunder the same conditions.ENGINEERING MATERIAL SPECIFICATIONWSS-M99G170-AWP 3948-b Page 2 of 3 3.3 CONDITIONING AND TEST CONDITIONSAll test values indicated herein are based on ma terial conditioned ina control led atmosphere of 23 +/- 2 C and 50 +/- 5 % relativehumidi
9、ty for not less than 24 h prior to testing and tested under thesame conditions unless otherwise specified.3.4 VOLUME RESISTIVITY, ohm-cm, min 1 E3(ASTM D 257)3.5 APPARENT THERMAL CONDUCTIVITY, W/m-K, min 3.2(ASTM D 5470)3.6 TENSILE STRENGTH, N/mm2, min 21.0(ASTM D 412)3.7 BREAKING STRENGTH, N/mm, mi
10、n 3.0(ASTM D 1458)3.8 ADDITIONAL REQUIREMENTSSpecific requirements for material and/or manufa ctured parts shall bespecified on the Engineering drawing, Engineerin g parts specificationand/or performance specification. All critical areas with respect tothese properties shall be clearly designated on
11、 the engineeringdrawing.3.9 SUPPLIERS RESPONSIBILITYAll materials supplied to this specification must be equivalent inal l characteristics to the material upon which approval wasoriginally granted.Pri or to making any change in the properties, composition,constr uction, color, processing or labeling
12、 of the materialorig inally approved under this specification, whether or not suchchange s affect the materials ability to meet the specificationrequir ements, the Supplier shall notify Purchasing, Toxicology andthe affected Materials Engineering activity of the proposed changesand obtain the writte
13、n approval of the Materials Engineeringactivity. Test data, t est samples and a new code identification areto be submitted with the request.Substance restrictions imposed by law, regulations or Ford, apply tothe materials addressed by this document. The restrictions aredefined in Engineering Materia
14、ls Specification WSS-M99P9999-A1.ENGINEERING MATERIAL SPECIFICATIONWSS-M99G170-AWP 3948-b Page 3 of 3 4. APPROVAL OF MATERIALSMat erials defined by this specification must have prior approval by theresp onsible Materials Engineering activity. Suppliers desiring approvalof thei r materials shall firs
15、t obtain an expression of interest from theaffec ted Purchasing, Design and Materials Engineering activity. Uponrequest, the Supplier shall submit to the affected Materials Engineeringactivity a completed copy of their laboratory test reports, signed by aqualified and authorized representative of th
16、e test faci lity, demonstratingful l compliance with all the requirements of this specification (testresults, not nominal values), the material designation a nd code number, andtes t specimens for Ford evaluation. Fords engineering approval of amateri al will be based on its performance to this spec
17、ification and on anassessment of suitability for intended processes and/or applications. Uponapprov al, the material will be added to the Engineering Material ApprovedSource List.5. GENERAL INFORMATIONThe information given below is provided for clarification and assistancein meeting the requirements
18、 of this specification.5.1 THERMAL RESISTANCEThe t hermal performance of a thermal conductor prepared from thesilicone rubber coated aluminum foil sheet stock specified herein canbe determined using var ious test methods called “thermal resistance“or “th ermal impedence“ tests. These tests take into
19、 accountvariations in the thermal conductivity of the conducting andinsulating materials caused by the adhesive and its filler, componentsurface finish, and clamping forces. For modeling purposes, thisda ta may be more appropriate than thermal conductivity which is aproperty of the bulk material. Th
20、ermal impedence and thermalinterf acial impedance can be obtained from the apparent thermalconductivity measurements from paragraph 3.5 using test method ASTMD 5470.5.2 THICKNESS*, ADHESIVE COATED, nominal, mm 0.173(ASTM D 374)*Thickn ess originally approved. Other thicknesses may be used asspecified on the engineering drawing.
