Specification Alloyed quenched and tempered steel and. JED precipitation hardening steel 036M

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1 Specification Class: Heat-treatable steel Class No.:11 Alloyed quenched and tempered steel and JED precipitation hardening steel 036M Previous Edition Part name (for databases) Alloyed steel f. crankshaft Scope The specification refers to steels for the manufacture of crankshafts: Alloyed steel for quenching and tempering in quenched and tempered condition. Replacement for SC MAT11M specification. Precipitation hardening ferritic-pearlitic steel with addition of vanadium, in precipitation hardened condition. 2 General requirements The precipitation hardening steels must exhibit a ferritic-pearlitic precipitation hardened structure (condition BY) as a result of controlled cooling after heat forming. The marking "BY" must be applied in addition to the WABCO logo on parts which are made of precipitation hardened steel. The finished parts shall be homogeneous and free from pores, blisters and other defects. The parts shall have a smooth surface in accordance with the applied forming process. The parts must not show any defects such as cracks, voids, etc. within their structure. The requirements for finished parts can be taken from the drawing and the special part specification. All materials, even ingredients in small quantities (e.g. cadmium), which are detrimental to health or to the environment are banned from being used. In order to ensure corrosion protection, steel parts must be subjected to a surface protection treatment suited for each case of application (galvanizing, painting). If the material standards established on a national level determine narrower limits than those defined in chapter 4 of the present specification for the properties of materials released in the "Release of Suppliers" pertinent to this specification, the supplied material must correspond to these narrower limits. 3 Thermal range of application Continuous operational temperature range: -60 C to +200 C For the thermal range of application of the finished parts the range of application of a possibly applied surface coating has to be taken into consideration. Compiler Approved Product Group: 4961 Continuation page 2 to 5 Karthi S JED.dot Template version 03 Hans Voss Doc. Code Language Rev en - E

2 JED-036M : Page 2 4 Properties 4.1 Mechanical properties Steel for quenching and tempering in quenched and tempered condition On specimens according to ISO the following properties have to be guaranteed: 16 mm >16 40 mm > mm Tensile strength (ISO 6892): 900 to to to 850 [N/mm²] Hardness (ISO 6507): 280 to to to 265 [HV10] Yield stress (ISO 6892): > 650 > 590 > 460 [N/mm²] Percentage elongation at fracture (ISO 6892): > 11 > 13 > 13 [%] Notched-bar impact strength (ISO 148): > 30 > 35 > 35 [J] Dispersion bands of Rockwell-C-hardness; hardenability tested in end-quench test.

3 JED-036M : Page 3 Precipitation hardening steel in condition BY On specimens according to ISO the following properties have to be guaranteed in the direction of the fibre: Tensile strength (ISO 6892): 820 to 1000 [N/mm²] Hardness (ISO 6507): 255 to 310 [HV10] Yield stress (ISO 6892): > 550 [N/mm²] Percentage elongation at fracture (ISO 6892): > 12 [%] Reduction of area after fracture (ISO 6892): > 25 [%] 4.2 Chemical composition [%] Quenched and tempered steel Precipitation hardening steel Carbon (C): 0.28 to to 0.4 Silicon (Si): max to 0.8 Manganese (Mn): 0.5 to to 1.5 Phosphorus (P): max max Sulphur (S): max to 0.07 Chromium (Cr): 0.9 to 1.25 max Vanadium (V): 0.08 to Further properties The steels are suitable for hot forming, cold forming, hardening and quenching and tempering. 4.4 Inclusion rating and Microstructure for quenched and tempered steel (not normative) Pleaser refer the annexture 1 for recommended inclusion rating and microstructure 5 Conditions of delivery The material and the finished parts must correspond to the technical conditions of delivery defined in JED Document Versions Revision Date Changes Initial version. A Table of released steels updated B Complete update C Error correction in requirements for chemical composition D Requirements for precipitation hardening steels added E Requirement for core hardness also expressed explicitly in Vickers hardness in addition to tensile strength. Replacement for SC MAT11M.

4 JED-036M : Page 4 Annexture 1 1. Inclusion rating Inclusion rating shall be checked as per ISO 4967:2013 (IS 4163: 2004) and inclusion rating shall not exceed the following limits Type A (Sulfide type) Type B (Aluminate type) Type C (Silicate type) Type D (Globular oxide type) Fine Thick Type (DS) (Single globular type) 2. Grain size Steel shall be procured with fine grain size and minimum grain size rating of the material shall be No.7.0 ASTM E Heat treatment Hardening and tempering treatment shall be carried out in the oxygen free atmosphere and decarburization on the surface shall not exceed 1% of the finished products diameter. Microstructure shall show fine tempered martensite, free from retained austenite. Following are the acceptable and not acceptable microstructures Magnification 750X Acceptable microstructure Not Acceptable microstructure Hardened and tempered martensite Un-tempered martensite

5 JED-036M : Page 5 Magnification 500X Acceptable microstructure Not Acceptable microstructure Hardened and tempered martensite Un-tempered martensite