Abstract

This work is devoted to transformations in tool steel for hot pressing after isothermal holding in the bainite range and heating in the range of 500–780°C. Medium carbon steel (0.44% C) is investigated: Si–Cr–Ni–Mn–Mo–V–Ti–Nb. It is shown that, at heating to 630°C after isothermal holding, when the amount of newly formed austenite is comparatively low, the properties of steel are determined mainly by structural variations in bainite sectors and its hardness continuously decreases. At higher heating temperatures, the amount of austenite sharply increases, and its subsequent decomposition upon cooling leads to a significant increase in steel hardness.

中文翻译：

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贝氏体区等温保温后加热时热压工具钢的组织和硬度变化

摘要

这项工作致力于在贝氏体范围内等温保持并在500–780°C范围内加热之后，进行热压模具钢的转变。研究了中碳钢（0.44％C）：Si–Cr–Ni–Mn–Mo–V–Ti–Nb。结果表明，在等温保温后加热到630℃时，当新形成的奥氏体的量相对较低时，钢的性能主要由贝氏体扇区的结构变化决定，并且其硬度持续降低。在较高的加热温度下，奥氏体的量急剧增加，并且其随后在冷却时分解导致钢硬度的显着增加。