| 摘要 |
<p>A powder metallurgy article, which is particularly adapted to the manufacture of hot working rolls and tooling as well as high toughness cold work tooling such as shear blades and slitter knives, formed from compacted prealloyed powder of an alloy consisting essentially of, in weight percent, manganese 0.2 to 1.5, silicon 2 max., chromium 1.5 to 6, molybdenum 0.50 to 6, sulfur 0.30 max., vanadium 7 to 10, carbon expressed by the formula (.25 minimum, .40 maximum + .16 x percent vanadium), optional carbide forming elements such as tungsten and columbium m amounts up to 5 percent (with the corresponding stoichiometric carbon required for balance) may partially replace vanadium, optional cobalt additions may be included for heat resistance and balance iron and incidental impurities; the article is characterized by a fully martensitic structure with essentially no carbon in the steel matrix in excess of the carbon necessary to combine with the vanadium present to form vanadium carbides and to insure said fully martensitic structure.</p> |
