Patent ID: 6280685
Filing Date: 2001-08-28
Classification: C21D,C22C

Abstract:
A tool steel composition for making tools that withstand heat and that work under high levels of stress, said tool steel containing a set of alloying elements which is balanced so as to provide sufficient quenchability for obtaining uniform properties throughout the thickness of parts of large size comprising in weight percentage:a) carbon as a basic hardening element in the range of 0.33 to 0.37%,b) complementary hardening elements chromium and molybdenum in the ranges of:Cr 2.0%-4.0%Mo 1.2%-2.2%such that said tool steel does not include a preponderance of chromium carbides which are harmful for stability in operation,c) complementary hardening elements vanadium and tungsten are present in the ranges of:V 0.4%-1.0%W 1.5%-3.0%which provides for increasing structural resistance to heating and for raising the highest acceptable operating temperatures, andd) the following elements in the following ranges:Co 1.0%-5.0%Si 0%-1.0%Mn 0%-1.0%Ni 0%-1.0%the balance being mainly constituted by iron and inevitable impurities.