| 摘要 |
<p>Process for manufacturing rolled steel products, for example tension steels suitable for threading or similar, according to which steels having a C content of between 0.50 and 0.80 % by weight, an Si content of between 0.20 and 0.60 % by weight, and a Mn content of between 0.30 and 0.80 % by weight are subjected, by means of cooling after hot rolling provided by the rolling heat on the output side of the finishing stand, to a surface hardening operation in such a way that the material is immediately and completely transformed into martensite in an edge region, whereas the heat content remaining in the central region causes, during subsequent cooling, the tempering of the martensitic edge region which does not go beyond the bainite region. The process is characterized in that after cooling, cold working is effected followed by tempering. The degree of elongation is preferably 0.5 to 1.5 %; tempering is preferably effected at a temperature between 350°C and 380°C and for a hold time of 5 to 60 seconds at maximum temperature. With this process it is possible to manufacture, in a simple and a profitable manner, rolled steel products, for example tension steels, which fully comply with the requirements of the building industry as regards deformability and mechanical characteristics.</p> |
