1、 ENGINEERING MATERIAL SPECIFICATION Date Action Revisions Rev. 1 2017 09 06 Revised See Summary of Revisions J. Schenk, EU 2012 01 10 Released D. Jordan, NA, A. Toennessen, EU Controlled document at www.MATS Copyright 2017, Ford Global Technologies, LLC Page 1 of 11 STEEL, SHEET, COLD ROLLED, HIGH S
2、TRENGTH WSS-M1A367-A11/A12/A13/A14 SOLID SOLUTION STRENGTHENED STEEL, SHEET, COLD ROLLED, HIGH STRENGTH WSS-M1A367-A21/A22/A23/A24/A25 BAKE HARDENABLE STEEL, SHEET, COLD ROLLED, HIGH STRENGTH WSS-M1A367-A33/A34/A35/A36/A37/ MICRO-ALLOYED HIGH-STRENGTH LOW-ALLOY A38/A39 STEEL, SHEET, HOT ROLLED, HIGH
3、 STRENGTH WSS-M1A367-A44/A45/A46/A47/A48/ MICRO-ALLOYED HIGH-STRENGTH LOW-ALLOY A49/A50/A51/A52 Note: Steels shown in gray typeface are not in the Global material strategy and should not be used without approval from the Global Sheet Metal Tech Club. 1. SCOPE The materials defined by these Global sp
4、ecifications are fully killed, fine grained, high strength steel sheet with specified minimum yield strength between 180 MPa and 700 MPa, suitable for cold forming such as stamping, roll forming and tube making, and use in automotive applications. The specification applies to uncoated and coated ste
5、el sheet generally categorized as high strength steels: - Cold Rolled, Solution Strengthened Variants - Cold Rolled, Bake Hardenable Variants - Cold Rolled, Micro-alloyed High-Strength Low-Alloy Variants - Hot Rolled, Micro-Alloyed High-Strength Low-Alloy Variants The steel sheet may achieve its fin
6、al thickness by cold rolling, hot rolling, continuous thin-strip casting, or other means. All requirements of the specific variant are to be met regardless of the final thickness reduction method. Specification WSS-M1P94-A shall be used where pre-coating by the steel supplier is required. All requir
7、ements of the specific variant are to be met with or without pre-coating, except as noted in these specifications or as noted as exceptions on the Engineering Drawing. 2. APPLICATION These Global specifications were released originally for automotive body and chassis parts. 2.1 LIMITATIONS Common Gl
8、obal Grade Names are provided for information purposes and are not intended to be used on Engineering Drawings or CAD files. Not all grade / gauge / width / coating combinations are available. Contact Product Development Materials Engineering for assistance or Global Materials and Fastener Standards
9、 () for help in locating the responsible engineer. Variants shown with an asterisk and gray typeface in Tables 1-4 presently are not in the Global material strategy and should not be used without approval from the Sheet Metal Tech Club. ENGINEERING MATERIAL SPECIFICATION WSS-M1A367-A11/A52 Copyright
10、 2017, Ford Global Technologies, LLC Page 2 of 11 Sources for these grades may not exist in your region. Contact Product Development Materials Engineering for assistance or for help in locating the responsible engineer. Material supplied to these specifications may contain titanium or other transit
11、ion metals as alloying additions. Such alloyed steels, if subsequently surface treated by a nitrocarburising and/or oxidizing process, risk becoming embrittled due to the formation of ultrafine TiN or other precipitates. Accordingly, special consideration should be given to low carbon steel that con
12、tains intentional additions of titanium or other transition metals for parts that may be subjected to nitrocarburising and/or oxidizing processes. 3. REQUIREMENTS Note: Drawing Precedence Any part specific exceptions or restrictions of requirements listed in paragraph 3 shall be recorded on the part
13、 drawing and have to be considered in all engineering testing and attribute confirmation checklists. 3.1 APPROVED SOURCES This specification requires the use of approved sources. Only the sources identified on the Ford Approved Source List (ASL) can be used when this specification is listed on the d
14、rawing, CAD file, or other documents. The list of approved sources is located within Ford at or available externally through a Ford Materials Engineer. See also paragraph 4.1. 3.2 CHEMICAL COMPOSITION AND MICROSTRUCTURE (ASTM E112, JIS G0320, ISO 4967 / ASTM E45) 3.2.1 Chemical Composition The uppe
15、r and lower limits of chemical composition of the controlled elements shall be established by the supplier and included in the suppliers Control Plan. Guidelines for chemical composition are provided in section 4.4. Heat and/or check analyses shall be provided as part of the initial material source
16、approval process in a format suitable for upload into the Ford Material Database. The choice of strengthening mechanism and the method of inclusion control, inclusion shape control, and/or stabilization shall be identified for the specific process path in the suppliers Control Plan. 3.2.2 Microstruc
17、ture The grain size number shall be established as part of the initial material source approval process and shall be consistent (within 1 unit) throughout the thickness of the sheet. The steel sheet shall be free from internal defects that adversely affect manufacturing or part functionality. Exampl
18、es of defects may include: pipe laminations, non-metallic inclusions, segregation, and blowholes. Non-metallic inclusion content shall not exceed a rating of 2.0 for thin and 2.0 for heavy when tested in accordance with ASTM E 45 Method D, Plate I-r, by analysis at 100X. ENGINEERING MATERIAL SPECIFI
19、CATION WSS-M1A367-A11/A52 Copyright 2017, Ford Global Technologies, LLC Page 3 of 11 3.3 MECHANICAL PROPERTIES (ASTM E8M, ASTM E517, ISO 6892-1, EN 10325, ISO 10113, ISO 10275, JIS Z 2241, JIS Z 2254, ASTM E 646) For initial approval requirements see paragraph 4.1. Mechanical properties are valid in
20、 the longitudinal direction. Certification of ongoing production material shall be in accordance with regional and/or local requirements. Yield Strength is defined as lower yield stress or 0.2% proof stress (for materials without marked yield point). For the determination of mechanical properties, t
21、he material cross sectional area shall be defined as that of the steel substrate only; contribution of any metallic and/or organic coating to the cross-sectional area used for stress calculation is neglected. (i.e. Zn, e-coat and/or paint are not included). This method of determining the cross secti
22、onal area of the test bar will be used as the referee method in all cases where the mechanical properties of the incoming material are in dispute. Note: UTS max values for Table 1-4 grades are not required attributes from the steel supplier but can be used as representative values for calculations t
23、hat require a max value. ASTM Total Elongation is measured with an ASTM (50 mm) test bar (ASTM E 8M). EN Total Elongation is measured with an ISO II (80 mm) test bar (ISO 6892-1). JIS Total Elongation is measured with a JIS #5 test bar (JIS Z 2241). Plastic Strain Ratio (r-value) is defined for a sp
24、ecific test direction with respect to the rolling direction. It is measured at 20% total elongation (or maximum uniform elongation if less than 20%). See ASTM E 517, ISO 10113, or JIS Z 2254. Average Plastic Strain Ratio (ravg) is calculated as a weighted average of the individual r-values, i.e., (
25、0o + 90o + 2 x 45o ) / 4 For grades with ravg requirements, data is collected for initial source approval. Ongoing certification to ravg requirements is not required for all coils. However, disputes will be settled using longitudinal, transverse and diagonal test bars sampled from the suspect materi
26、al. Strain Hardening Exponent (n-value) is measured over the range 10-20% strain (or 10% to end of uniform elongation if less than 20%). See ASTM E646 or ISO 10275. If uniform elongation is less than 12%, n-value shall be reported as nUE = UE (n at uniform elongation equals true strain at uniform el
27、ongation.) Required n-value measurements are only valid for material thicknesses up to 6.4 mm. For gauges over 6.4 mm n-values are not required. BHI (Bake Hardening Index) is defined as the increase in lower yield strength due exclusively to the baking portion of the following: Strain 2% in the long
28、itudinal direction, note stress and release load. Bake at 170 (+/- 2) deg C peak metal temperature for 20 (+/- 1) minutes. Determine post-bake yield strength per ASTM E 8M, ISO 6892-1, EN 10325, or JIS Z 2241. BHI is the difference between the pre-bake stress at 2% strain and the post-bake yield str
29、ength. BHI neglects the contribution of work hardening to yield strength and includes only the contribution due to thermal response. Actual processing conditions (temperature profiles and strain conditions) dictate the observed strength levels of individual parts. ENGINEERING MATERIAL SPECIFICATION
30、WSS-M1A367-A11/A52 Copyright 2017, Ford Global Technologies, LLC Page 4 of 11 Aging: Maximum storage time (“Aging limits”) for BH grades have to be agreed with regional manufacturing / purchasing activities. See e.g. technical delivery conditions document in Europe. Mechanical properties are reporte
31、d following standard rounding rules. Table 1: Mechanical Properties for Cold Rolled, Solution Strengthened Variants Variant A11 A12 A13 A14 Common Global Grade Name CR180 CR210 CR240 CR270 Yield Strength, MPa (min) 180 210 240 270 Yield Strength, MPa (max) 240 270 300 330 Tensile Strength, MPa (min)
32、 300 320 340 360 Tensile Strength, MPa (max) 400 420 440 460 ASTM Total Elongation, % (min) 35 33 30 28 EN Total Elongation, % (min) 33 31 28 26 JIS Total Elongation, % (min) 39 37 34 32 ravg (min) 1.3 1.3 1.1 1.0 r0 (min) 1.2 1.1 1.0 1.0 n value (min) 0.20 0.19 0.15 0.14 Table 2: Mechanical Propert
33、ies for Cold Rolled, Bake Hardenable Variants Variant A21 A22 A23 A24* A25 * Common Global Grade Name CR180B2 CR210B2 CR240B2 CR270B2 CR300B2 Yield Strength, MPa (min) 180 210 240 270 300 Yield Strength, MPa (max) 240 270 300 330 360 Tensile Strength, MPa (min) 300 320 340 360 390 Tensile Strength,
34、MPa (max) 370 400 440 460 490 BHI, MPa(min) 30 30 30 30 30 ASTM Total Elongation, % (min) 35 33 30 28 26 EN Total Elongation, % (min) 33 31 28 26 24 JIS Total Elongation, % (min) 39 37 34 32 30 ravg (min) 1.3 1.1 1.1 0,9 0.9 r0 (min) 1.1 1.1 1.0 0.9 0.9 n value (min) 0.19 0.17 0.17 0.15 0.14 * Varia
35、nts shown with an asterisk and gray typeface are not in the Global material strategy and should not be used without approval from the Sheet Metal Tech Club. Sources for these grades may not exist in your region. Contact Product Development Materials Engineering for assistance or for help in locatin
36、g the responsible engineer. ENGINEERING MATERIAL SPECIFICATION WSS-M1A367-A11/A52 Copyright 2017, Ford Global Technologies, LLC Page 5 of 11 Table 3: Mechanical Properties for Typically Cold Rolled, Micro-alloyed High-Strength Low-Alloy Variants Variant A33 A34 A35 A36 A37 A38 A39 * Common Global Gr
37、ade Name CR240LA CR270LA CR300LA CR340LA CR380LA CR420LA CR500LA Yield Strength MPa (min) 240 270 300 340 380 420 500 Yield Strength MPa (max) 320 350 380 420 460 520 600 Tensile Strength MPa (min) 320 330 370 410 450 480 560 Tensile Strength MPa (max) 430 460 490 530 570 600 700 ASTM Total Elongati
38、on, % (min) 28 26 24 22 20 18 16 EN Total Elongation, % (min) 26 24 22 20 18 16 14 JIS Total Elongation, % (min) 32 30 28 26 24 22 20 n value (min) 0.15 0.15 0.14 0.13 0.12 0.11 0.09 Table 4: Mechanical Properties for Typically Hot Rolled, Micro-Alloyed High-Strength Low-Alloy Variants Variant A44 A
39、45 A46 A47 A48 A49 A50 A51* A52 Common Global Name HR270LA HR300LA HR340LA HR380LA HR420LA HR500LA HR550LA HR600LA HR700LA Yield Strength, MPa (min) 270 300 340 380 420 500 550 600 700 Yield Strength, MPa (max) 350 380 420 460 520 600 650 720 850 Tensile Strength MPa (min) 330 370 410 450 480 560 61
40、0 680 750 Tensile Strength, MPa (max) 470 500 540 570 600 700 750 850 950 ASTM Total Elongation, % (min) 29 27 25 23 22 20 18 16 12 EN Total Elongation, % (max) 27 25 23 21 20 18 16 14 10 JIS Total Elongation, % (max) 33 31 29 27 26 24 22 - - n value (min) 0.15 0.14 0.13 0.12 0.11 0.09 0.08 - - * Va
41、riants shown with an asterisk and gray typeface are not in the Global material strategy and should not be used without approval from the Sheet Metal Tech Club. Sources for these grades may not exist in your region. Contact Product Development Materials Engineering for assistance or for help in loca
42、ting the responsible engineer. ENGINEERING MATERIAL SPECIFICATION WSS-M1A367-A11/A52 Copyright 2017, Ford Global Technologies, LLC Page 6 of 11 3.4 DIMENSIONS AND DIMENSIONAL TOLERANCES 3.4.1 Thickness and Thickness Tolerance Unless otherwise specified by Ford Motor Company on the Engineering Drawin
43、g or Purchase Order, the tolerance for thickness shall comply with ESBAU5-1N260-AA or latest level. 3.4.2. Other Dimensional Tolerances Length, width, flatness, camber, out-of-square, mass and other tolerances for the material as delivered by the steel supplier are defined by the relevant local manu
44、facturing activity, e.g. by referring to the “Sheet Metal Coils and Blanks - Technical Delivery Conditions” document used by Ford Europe or regional industry standards like the ASTM A 568M, A 635M, JFS A 1001, JFS A 2001, EN 10051, EN 10131 and EN 10143 if applicable. 3.5 FORMABILITY In conjunction
45、with the material supplier and Product Development Materials Engineering, the affected local manufacturing activity shall approve the formability of this material by means of laboratory test(s), manufacturing trial(s), and/or another mutually acceptable alternative, using the equipment and methods t
46、hat are proposed for production. If needed to enable the fabrication of a specific component, restricted tolerances and/or additional materials property requirements (i.e., the “quality level“ of the steel) shall be developed by the affected manufacturing activity and the steel supplier. Examples in
47、clude, but are not limited to: restricted yield strength range, restricted gauge tolerance, specified minimum n-value, and specified surface roughness. The “quality level“ of the steel for a specific component: shall not conflict with specified requirements in paragraph 3 of this Engineering Materia
48、l Specification shall be described and documented in detail by the local manufacturing activity by using the Metal Specification sheets (i.e., GSHT3, EU55, EU2066) shall be a mandatory extension of these Engineering Material Specifications Acceptance of subsequent orders by the steel supplier for a
49、given component at the agreed upon quality level implies that all steel supplied will be of a comparable quality level and will form that part satisfactorily as defined and recorded by the manufacturing activity. 3.6 JOINABILITY In conjunction with the material supplier and Product Development Materials Engineering, the affected local manufacturing activity shall, as part of the initial material source approval process, app
