1、 ENGINEERING MATERIAL SPECIFICATION Date Action Revisions Rev. 3 2011 03 21 Revised Changed Melt flow Rate G. Kowalski, NA 2005 09 14 Revised Inserted 3.0; Deleted 3.1, 3.2, 3.3, 3.8, 3.9 & 4 1989 07 03 SM/EQ24042 TP Released M. Siewert Printed copies are uncontrolled Copyright 2011, Ford Global Tec
2、hnologies, LLC Page 1 of 5 ACETAL (POM) COPOLYMER, MODIFIED, WSK-M4D618-A2 HIGH IMPACT GRADE 1. SCOPE The material defined by this specification is a polyurethane modified thermoplastic acetal copolymer based on trioxane. 2. APPLICATION This specification was released originally for materials used f
3、or fixing grommets. 3. REQUIREMENTS Material specification requirements are to be used for initial qualification of materials. 3.0 STANDARD REQUIREMENTS FOR PRODUCTION MATERIALS Material suppliers and part producers must conform to the Companys Standard Requirements For Production Materials (WSS-M99
4、P1111-A). 3.4 MOLDING COMPOUND 3.4.1 Melt Flow Rate 3.0 - 10.0 g/ (ISO 1133/ASTM D 1238, 190 C, 2.16 kg) 10 minutes NOTE: For individual melt flow rates of approved materials see the Approved Source List. 3.5 MOLDED TEST SPECIMEN 3.5.1 Preparation of Test Specimens Unless otherwise specified all tes
5、ts shall be carried out on injection molded one-end gated test specimens. The following dimensions are required: A. 150 min x 10 x 4.0 +/- 0.2 mm (Tensile Bar, ISO 3167) B. 120 x 10 x 4.0 +/- 0.2 mm Specimens with shorter dimensions shall be cut from the center portion of the test specimen A and/or
6、B. The specimens shall be prepared according to ISO 294. No annealing allowed. ENGINEERING MATERIAL SPECIFICATION WSK-M4D618-A2 Printed copies are uncontrolled Copyright 2011, Ford Global Technologies, LLC Page 2 of 5 3.5.2 Density 1.34 - 1.39 g/cm3 (ISO 1183, Method A/ASTM D 792, Method A1) 3.5.3 T
7、ensile Strength at Yield 37 MPa min (ISO R 527/ASTM D 638M, 150 min x 10 x 4.0 +/- 0.2 mm specimen, 50 mm/minute test speed) 3.5.3.1 Elongation at Break 25% min (Test Method according to para 3.5.3) 3.5.4 Flexural Modulus 1.2 GPa min (ISO 178/ASTM D 790M, Method I, Procedure A, 80 x 10 x 4.0 +/- 0.2
8、 mm specimen, 2 mm/min test speed, 64 mm support span, the radius of the loading nose 5 +/- 0.1 mm and of the supports 2.0 +/- 0.2 mm) 3.5.5 Shear Modulus at 23 C Report Value MPa (ASTM D 4065, forced constant amplitude, fixed frequency of 1 Hz +/- 15%, strain level below 1%. Specimen approx. 60 x 1
9、0 x 4.0 +/- 0.2 mm cut from the center of specimen A. Specimen length between clamps 35-40 mm Soak time at each temperature interval 3 minutes minimum) Additionally, a Shear Modulus vs. Temperature curve shall be plotted for -50 to +130 C temperature range, at 5 C minimum intervals. The plotted curv
10、e must be within tolerance range shown on page 6. 3.5.6 Impact Strength, Izod (ISO 180, Method A/ASTM D 256, Method A, 80 x 10 x 4.0 +/-0.2 mm specimen, 10 specimens for each test) 3.5.6.1 At 23 +/- 2 C 6.5 kJ/m2 min 3.5.6.2 At -40 +/- 2 C 3.5 kJ/m2 min 3.5.6.3 At -20 +/- 2 C 5.0 kJ/m2 min The test
11、specimens must be conditioned for minimum of 6 h at the above specified temperature prior to impact test. Low temperature testing shall be done within the cold box, if not possible, test can be conducted outside, but within 5 s. 3.5.7 Heat Deflection Temperature (ISO 75/ASTM D 648, 120 x 10 x 4.0 +/
12、- 0.2 mm specimen at standard deflection of 0.32 +/- 0.01 mm) 3.5.7.1 At 1.80 MPa 66 C min 3.5.7.2 At 0.45 MPa 130 C min ENGINEERING MATERIAL SPECIFICATION WSK-M4D618-A2 Printed copies are uncontrolled Copyright 2011, Ford Global Technologies, LLC Page 3 of 5 3.5.8 Heat Aging Performance (ISO 188/AS
13、TM D 573, 150 +/- 50 air changes/h, 1000 h at 130 +/- 2 C. Unaged property values shall be determined at the time of the aged properties determination) 3.5.8 1 Tensile Strength Change +/- 20% (Test Method per para 3.5.3) 3.5.8.2 Impact Strength, Izod Change +/- 25% (Test Method per para 3.5.6.1, spe
14、cimens to be notched before heat aging) 3.6 FOGGING (SAE J1756, 3 h at 100 C heating, 21 C cooling plate, post test conditioning 1 h and 16 h) Fog Number 80 min Formation of clear film, droplets or crystals is cause for rejection. 3.7 FLAMMABILITY (ISO 3795) Burn Rate 100 mm/minute max The specimen
15、size required for material approval is 355 x 100 x 1.5 +/- 0.1 mm with a smooth surface. 4. GENERAL INFORMATION The information given below is provided for clarification and assistance in meeting the requirements of this specification. 4.1 COEFFICIENT OF LINEAR THERMAL EXPANSION 13 - 16-5/ C (ASTM D
16、 696) 4.2 MOLD SHRINKAGE (ISO 2577, approx. 150 x 100 x 3.2 +/- 0.2 mm injection molded specimen) 4.2.1 Molding Shrinkage After 48 h at 23 +/- 2 C 2.0 - 2.5% 4.2.2 Post Shrinkage (Separate specimens required for each test) After 48 h at 80 C 0.1 - 0.4% After 30 minutes at 120 C 0.1 - 0.4% ENGINEERIN
17、G MATERIAL SPECIFICATION WSK-M4D618-A2 Printed copies are uncontrolled Copyright 2011, Ford Global Technologies, LLC Page 4 of 5 4.3 WATER ABSORPTION 0.3 - 0.8% (ISO 62, 24 h/ASTM D 570, 24 h, 50 +/- 1 mm diameter, 3.1 +/- 0.1 mm thick specimen) 4.4 HARDNESS, DUROMETER D 72 - 80 (ISO 868/ASTM D 2240
18、) 4.5 DIMENSIONAL STABILITY The phrase “anneal after molding“ shall appear on engineering drawings when dimensional stability and/or improved frictional characteristics are engineering requirements. 4.6 RECYCLING CODE SAE or POM OPTIONAL 5. SUMMARY OF REVISIONS 2011 03 21 Revised Melt Flow Rate range and Heat Deflection Temperature. Shear Modulus requirement changed to report only Renumbered POM ENGINEERING MATERIAL SPECIFICATION WSK-M4D618-A2 Printed copies are uncontrolled Copyright 2011, Ford Global Technologies, LLC Page 5 of 5
