Performance Characteristics: Hardening in air, featuring a fine combination of hot strength, cracking resistance and impact toughness in work 600 Centigrade; Applications: Be used for cold mould such as punch die 、wire-drawing die、thread rolling mould 、cold heading mould and cold extrusion mould. Chemical Composition (%) C Si W Mo Cr S P 2.00~2.30 �0.40 0.60~0.90 �0.35 11.00~12.50 �0.030 �0.030 Heat Treatment:Annealing : 800 - 850 centigrade. Hardness after annealing : Max. 250 HB Stress relieving : 650 - 700 centigrade. Hot forming : 1050 - 850 centigrade. Hardening : 950 � 980 centigrade. Quenching media : Oil, Salt bath ( 220 - 250 centigrade or 500 - 550 centigrade ). Hardness after quenching : 64 - 66 HRC. Delivery condition: EAF or ESR; hot rolled or forging;black,machined surface;Annealing.