| 摘要 |
Method for reducing the segregated seams of a steel which has high mechanical strength and high wear resistance and whose composition comprises by weight: 0.30%≦̸C≦̸1.42%; 0.05%≦̸Si≦̸1.5%; Mn≦̸1.95%; Ni≦̸2.9%; 1.1%≦̸Cr≦̸7.9%; 0.61%≦̸Mo≦̸4.4%; optionally V≦̸1.45%, Nb≦̸1.45%, Ta≦̸1.45% and V+Nb/2+Ta/4≦̸1.45%; less than 0.1% of boron, less than 0.19% of (S+Se/2+Te/4), less than 0.01% of calcium, less than 0.5% of rare earths, less than 1% of aluminum, less than 1% of copper; the balance being iron and impurities resulting from the production operation. The composition further complies with: 800≦̸D≦̸1150 with D=540(C)0.25+245(Mo+3V+1.5Nb+0.75Ta)0.30+125Cr0.20+15.8Mn+7.4Ni+18Si. According to the method, the molybdenum is completely or partially replaced with double the proportion of tungsten so that W>0.21%, and Ti, Zr, C are adjusted so that, after adjustment, Ti+Zr/2≧0.2W, (Ti+Zr/2)×C≧0.07, Ti+Zr/2≦̸1.49% and D is unchanged at approximately 5%. Steel obtained and method for producing a steel workpiece. |
