MS-264 S克莱斯勒高强钢规范

Chrysler Group LLC Document Number: MS-264 Material Standard Date Published: 2010-06-09 Category Code: B-1 Change Level: AE EASL Requirement: Yes

Restricted: No

HIGH STRENGTH AND STRUCTURAL QUALITY STEELS - SHEET, STRIP, PLATE, FLAT BAR AND

WELDED MECHANICAL TUBING

1.0 GENERAL

CAUTION: Fasteners, springs or clips manufactured from this material that are surface treated to improve their cleanliness, appearance or corrosion resistance, may become hydrogen embrittled when exposed to the chemicals and coating methods used in processing. Consequently, if these parts are surface treated, it is required that they be hydrogen embrittlement relieved according to the procedures described in PS-9500.

1.1 Purpose of the Standard

This standard specifies the requirements for medium strength, high strength and ultra high strength cold rolled or hot rolled sheet, strip, plate and welded tubing. This standard follows much of the format and nomenclature of SAE-J1392 and SAE-J2340 but is different in several respects.

1.2 Purpose of the Material

High strength and structural quality steels are intended for use on parts which require specific minimum mechanical properties in order to meet applicable performance and safety standards. Typical applications include body panels, body structure components, bumpers, reinforcements, and chassis components.

1.3 Coverage of the Standard

High strength and structural quality steels are specified by strength level, type, and deoxidation practice. Available grades range from 25 ksi (172 MPa) to 120 ksi (827 MPa) minimum yield strength. Ultra-high strength, martensitic grades are specified by minimum tensile strength. Available grades range from 190 ksi (1300 MPa) to 220 ksi (1500 MPa). Formability of high strength materials can be more challenging than with low carbon mild steels because of greater springback concerns and reduced ductility. Advanced High Strength Steels (AHSS) include dual phase steels, partial martensitic steels, and TRIP steels, and are specified by minimum tensile strength. Available grades range from 490 MPa to 980 MPa minimum tensile strength materials.

Inclusion shape controlled grades as well as other chemistry requirements may be specified when special considerations apply, i.e., freedom from aging and stretcher strains or specific properties needed for dimensional control and forming. Most – if not all - automotive sheet steels are fully killed, and most of these are continuously cast.

High strength and structural quality steels achieve their properties through chemical composition and special thermo-mechanical processing and are generally not suitable for heat treatment by the part manufacturers. Subjecting these grades to heat treatment may lower the mechanical properties. Metallic Materials Engineering shall be consulted to specify the proper grade if annealing, normalizing, stress relief, or welding is to be performed.

This standard covers the mechanical properties, chemical composition, weldability, cleanability, and surface requirements for high strength steels.