1、 WORLDWIDE ENGINEERING STANDARDS Material Specification GMW15702 Plastic Molding Compounds Copyright 2013 General Motors Company All Rights Reserved September 2013 Page 1 of 15 1 Scope This standard provides a system for specifying significant properties of commonly used plastics, including unpigmen
2、ted and pigmented, unfilled and filled products. It is intended to apply to resins (not parts) primarily as used in the automotive and related industries. It is also intended to be used either as the sole descriptor of a material or within the body of a specification covering the common standard cha
3、racteristics required, whereas additional specialized requirements are detailed. Note: The resin supplier must provide a certification statement meeting the resin requirements per the callout of this standard. This certification must be loaded into the GM Material Specification File (MATSPC). 1.1 Ma
4、terial Description. 1.1.1 The material description is based on the principle that plastics should be described, insofar as is possible, in terms of specific performance characteristics desired in the resin, and that an infinite number of such descriptions can be formulated by the use of one or more
5、standard statements (based on standard tests), each designating a quality level of a property or characteristic. 1.1.2 Users of plastic resin can, by selecting different combinations of performance characteristics, specify different combinations of properties desired in various resins. 1.1.3 Possibl
6、e standard statements are defined in 8.1. 1.1.4 To permit line callout (e.g., designation on a part drawing, in the math data or in a component specification) of the material descriptions mentioned, the system includes a symbol for the general type of plastic resin to be used and a letter-number sym
7、bol for each quality level of each property or characteristic. Example: The complete GMW15702 for an automotive resin might be specified as follows: GMW15702-120014 ABSABSSymbolPA46-GF30Symbol = Symbol according to paragraph 1.2 (Coded Properties) = Properties are coded per Section 8.1. This part of
8、 the callout is optional on the part drawing/in the math data. It is required in the remarks field of the GM Materials File. Note: The addition of symbols following the 6-digit code is optional and at the discretion of the responsible Material Specialist. 8.1 System for Specifying Significant Proper
9、ties of Commonly Used Plastics. 8.1.1 Material Description. 8.1.1.1 The material description is based on the principle that plastics should be described, insofar as is possible, in terms of specific performance characteristics desired in the resin, and that an infinite number of such descriptions ca
10、n be formulated by the use of one or more standard statements (based on standard tests), each designating a quality level of a property or characteristic. 8.1.1.2 Users of plastic resin can, by selecting different combinations of performance characteristic, specify different combinations of properti
11、es desired in various resins. Suffix Symbols A through H are normally applicable to the resin as received. Suffix Symbols J through U are normally applicable to test specimens molded from the resin as received. Suffix Symbols V through Z covering environmental performance requirements are also norma
12、lly applicable to test specimens molded from the resin as received. 8.1.1.3 For a summary of all designated codes for compound properties, see Table 1. See 8.1.2 for the details of each designation. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for Res
13、aleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW15702 Copyright 2013 General Motors Company All Rights Reserved September 2013 Page 6 of 15 Table 1: Compound Properties Suffix Symbol Characteristic A Resin Type B Reinforcement and/or Fill
14、er D Specific Gravity E Viscosity F Melt Point G Moisture Content H Oxidative Stability J Hardness K Tensile Strength, Tensile Modulus L Elongation M Flexural Modulus N Flexural Strength P Stiffness Q Compressive Strength R Impact Strength S Deflection Temperature T Brittleness Temperature U Flammab
15、ility V Fogging W Heat Resistance Y Weather Resistance Z Other Characteristics 8.1.2 Detailed Description of Designations. 8.1.2.1 Resin Description (Suffix A). The resin description shall be as indicated by the numeral(s) following the suffix A-symbol (see Table 2). One or more suffix symbols may b
16、e used to describe the required resins. Example: A3, A42 = A heat stabilized, copolymer resin. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDAR
17、DS GMW15702 Copyright 2013 General Motors Company All Rights Reserved September 2013 Page 7 of 15 Table 2: Resin Description Designation Characteristic 1 Alloy 2 Blend 3 Copolymer 4 General Purpose/Homopolymer 5 Impact Modified 6 Single Stage 7 Transparent 8 Two Stage 9 Reprocessed 20 Flake 21 Liqui
18、d 22 Pellet 23 Powder 24 Sheet 25 Rope 26 Bulk 27 Granular 40 Blowing Agent 41 Fungicide 42 Heat Stabilizer 43 Lubricated 44 Nucleating Agent 45 Plasticizer 46 UV Stabilized 47 Reinforcement and/or Filler 60 Blow Molding 61 Coating 62 Extrusion 63 Foaming 64 Injection Molding 65 Plating 66 Rotocasti
19、ng 67 Slush Molding 68 Compression Molding 69 Transfer Molding 70 Cold Runner 71 Rim Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW1570
20、2 Copyright 2013 General Motors Company All Rights Reserved September 2013 Page 8 of 15 Note: Designations 1 thru 9 describe resin type, 20 thru 27 describe compound, 40 thru 47 describe additives, and 60 thru 71 describe process grade. 8.1.2.2 Reinforcement and/or Filler (Suffix B). Shall be descri
21、bed by amending the suffix B-symbol using letter designations in Table 3. Table 3: Reinforcement and/or Filler Designation Reinforcement/Filler A Glass Fibers B Glass Fibers (Coupled) C Glass Spheres (Solid) D Glass Spheres (Hollow) E Asbestos Fibers F Carbon Fibers G Graphite H Wood Flour J Mineral
22、 Filler K Calcium Carbonate L Talc M Carbon Black N Molybdenum Disulfide P Cotton Flock R Sisal T Dimethyl Polysiloxane (Polymeric Silicone) U Fluorocarbon Fiber V Fluorocarbon Granules 8.1.2.3 The reinforcement, expressed as mass percent (%), shall be specified by the second and third numeral(s) fo
23、llowing the amended suffix B-symbol with a tolerance as indicated by the first numeral following the amended suffix B-symbol (see Table 4). Examples: BA730 = 30% 3% glass fibers. BA725, BN45 = 25% 3% glass with 5% 0.5% molybdenum disulfide. Copyright General Motors Company Provided by IHS under lice
24、nse with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW15702 Copyright 2013 General Motors Company All Rights Reserved September 2013 Page 9 of 15 Table 4: Tolerances for Reinforcement and/or Filler Nume
25、ral Designation Tolerance BA1-BV1 Minimum Value BA2-BV2 Maximum Value BA3-BV3 0.1 BA4-BV4 0.5 BA5-BV5 1.0 BA6-BV6 2.0 BA7-BV7 3.0 Note: In the case of most reinforcement, the value shall be determined by ISO 3451-1 or ISO 3451-4 for polyamides. Otherwise, the test method shall be agreed upon between
26、 purchaser and supplier. 8.1.2.4 Density (Suffix D). As determined by ISO 1183 (Method A) or ASTM D792 (Method A), density shall be within the tolerance indicated by the letter following the D suffix (see Table 5), and the value shall be as indicated by the numerals following the D suffix times the
27、factor 0.001. Example: DH895 = 0.895 0.003. Table 5: Tolerances for Density Designation Tolerance DA Minimum Value DB Maximum Value DC 0.02 DD 0.03 DE 0.05 DF 0.001 DG 0.002 DH 0.003 DJ 0.004 DK 0.005 8.1.2.5 Viscosity (Suffix E). When the suffix E symbol is not amended by a letter, then the followi
28、ng method shall apply: 8.1.2.5.1 Relative Viscosity. As determined by ASTM D789, the relative viscosity shall be no less than the numeral(s) following the E-symbol times the factor 10 and no greater than an additional 25% of the suffix E-symbol numeral(s) times the factor 10. Example: E8 = 80 to 100
29、. 8.1.2.5.2 Viscosity Number. As determined by ISO 307, the viscosity number shall be no less than the numeral(s) following the EN-symbol. Example: EN100 - 100 cm3/g. 8.1.2.5.3 Melt Volume Flow Rate (Suffix EV). As determined by the test method for volume flow rate listed in ISO 1133, volume flow ra
30、te shall be within 30% of the value indicated by the numeral of the E-suffix symbol times the factor 0.01 cm/10 minutes. The standard test conditions for the test shall be given by the numbers for temperature and load following the suffix EV-symbol. Example: EV190/2.16/80 = 190 C/2.16 kg load/0.8 30
31、% cm/10 minutes. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW15702 Copyright 2013 General Motors Company All Rights Reserved Septembe
32、r 2013 Page 10 of 15 8.1.2.5.4 Melt Mass Flow Rate (Suffix EM). As determined by the test method for flow rate listed in ISO 1133, mass flow rate shall be within 30% of the value indicated by the final numerals of the E-suffix symbol times the factor 0.01 g/10 minutes. The standard test conditions f
33、or the test shall be given by the numbers for temperature and load following the suffix EM-symbol. Example: EM190/2.16/80 = 190 C/2.16 kg load/0.8 30% g/10 minutes. 8.1.2.6 Melting Point (Suffix F). 8.1.2.6.1 As determined by the test method for melting point listed in ISO 3146, Methods A or B, or I
34、SO 11357-3 shall be within a tolerance of 3 C of the value indicated by the numeral of the suffix F-symbol expressed in degrees Celsius. Example: F185 = 185 C 3 C. 8.1.2.6.2 When the F-suffix symbol is amended by a letter following the F-symbol, then the following method shall apply: 8.1.2.6.2.1 Vic
35、at Softening Point per ISO 306. Using a heating rate of 50 C/h at a load of 50 N, Vicat softening point shall be indicated by the letter C following the F-symbol. Example: FC90 = Vicat per ISO 306 of 90 C 3 C. 8.1.2.7 Moisture Content (Suffix G). 8.1.2.7.1 As determined by the test method for moistu
36、re content ISO 15512, Method A or Method B, for polyamides and measured on the resin as received, moisture content shall not exceed the value shown following the suffix G-symbol times the factor 0.01%. Example: G30 = 0.3% maximum. 8.1.2.7.2 When the G-suffix symbol is amended by a letter following t
37、he G-symbol, then the following method shall apply: 8.1.2.7.2.1 Volatile Loss. As determined by the test method described in ISO 176 (Method B) or ASTM D1203 (Method B), volatile loss shall not exceed the value indicated by the numeral or numerals following the suffix symbol expressed as mass percen
38、t (%). 8.1.2.7.2.2 Where the test temperature is not appropriate, other temperatures may be specified by amending the suffix symbol as follows: GA = 70 C GB = 80 C GC = 100 C GD = 105 C GE = 120 C GF = 150 C Example: GA2 = 2 mass percent volatile loss when tested at 70 C. 8.1.2.8 Oxidative Stability
39、 (Suffix H). 8.1.2.8.1 Only for Polypropylene. Resin specimens taken from incoming shipment, or test plaque molded in the same manner as intended method of processing shall be tested. 8.1.2.8.2 Specimen shall be tested for thermal oxidative stability in an air ventilation oven at 150 C 3 C for the p
40、eriod of time indicated by the number behind the suffix H-symbol in hours (tolerance 1 h). 8.1.2.8.3 Test specimens shall not become crazed, friable in appearance, and shall not become brittle. Brittleness shall be determined by removing specimens from test apparatus, placing on a flat surface, and
41、subjecting to a light compressive force. 8.1.2.8.4 Test to ISO 4577 or ASTM D3012. Examples: H168 = 168 h 1 h. H336 = 336 h 1 h. 8.1.2.9 Shore Hardness (Suffix JS). Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking p
42、ermitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW15702 Copyright 2013 General Motors Company All Rights Reserved September 2013 Page 11 of 15 8.1.2.9.1 When the suffix JS-symbol is amended by the letters A or D, hardness shall be determined by the test method described in
43、ISO 868 using either the Shore A or Shore D scale as indicated by the final amending letter. 8.1.2.9.2 The hardness shall be as shown by the numerical value following the amending letter with a tolerance of 5 points for Shore A values and 3 points for Shore D values. Examples: JSA55 = (55 5) (Shore
44、A). JSD45 = (45 3) (Shore D). 8.1.2.10 Tensile Modulus (Suffix KM). 8.1.2.10.1 Tensile Modulus shall be determined by ISO 527 between 0.05% to 0.25% strain using specimens as defined in ISO 3167, 4 mm thick, Type A bar. 8.1.2.10.2 Speed of test shall be 1 mm/minute. 8.1.2.10.3 The value determined s
45、hall be no less than the numeral or numerals following the suffix KM-symbol times the factor 10 MPa. Example: KM12 = 120 MPa minimum. 8.1.2.11 Tensile or Yield Strength (Suffix KS). 8.1.2.11.1 Tensile Strength at Break (for materials which do not exhibit a definite yield point) and Yield Strength (f
46、or materials which do exhibit this property) shall be determined by ISO 527 using specimens as defined in ISO 3167, Type A bar. ISO 37 shall be followed for thermoplastic elastomer (TPE) materials. 8.1.2.11.2 Speed of test shall be 50 mm/minute for unfilled materials or 5 mm/minute for filled grades
47、, or as agreed upon between purchaser and supplier for those materials not listed. For TPE materials, speed of test shall be 500 mm/minute. 8.1.2.11.3 The value determined shall be no less than the numeral or numerals following the suffix KS-symbol times the factor 0.1 MPa. 8.1.2.12 Elongation (Suff
48、ix LS). 8.1.2.12.1 Elongation at Break (for materials which do not exhibit a definite yield point) and Elongation at Yield (for materials which do exhibit this property) shall be determined by ISO 527 and shall be no less than the numeral value following the suffix LS-symbol times the factor 0.1%. I
49、SO 37 shall be followed for TPE materials. 8.1.2.12.2 Speed of test shall be 50 mm/minute for unfilled materials or 5 mm/minute for filled grades, or as agreed upon between responsible GM Materials Engineer and supplier for those materials not listed. For TPE materials, speed of test shall be 500 mm/minute. 8.1.2.13 Flexural
