warmarbeits - tool steel, esp. for use at temperatures above 600 amp; amp; uarr; * amp; amp; uarr; c

摘要

A hot work steel with very high resistance to tempering and a very high strength at elevated temperatures, a good ductility and a comparatively low content of expensive alloying elements; the steel contains in weight percent: 0.30-0.45 C, 0.2-1.0 Si, 0.3-2.0 Mn, 2.0-3.5 Cr, 1.5-2.5 (W/2+Mo), 0.8-1.5 V, 0-0.01 B, balance essentially only iron and impurities in normal quantities; for a further embodiment the steel contains a maximum of 1.0, preferably a maximum of 0.5 and suitably a maximum of 0.3% coba in the hardened and tempered condition the steel has a fine grain lath-martensitic or partly bainitic microstructure which is free from retained austenite, and which contains a very finely dispersed intergranular precipitation of carbides, among which vanadium carbides are the dominating carbide phase.