Welding of stainless steels-physical metallurgy aspects
- 作者：Staffan Hertzman
- 会议时间：2013-06-01
- 关键词：stainless ; weld metallurgy ; physical metallurgy ; thermodynamics
- 作者单位：Outokumpu Stainless Research Foundation,Brinellv(a)gen 23,SE114 28 Stockholm,Sweden
- 母体文献：第五届宝钢学术年会论文集
- 会议名称：第五届宝钢学术年会
- 会议地点：上海
- 主办单位：中国金属学会
- 语种：chi
摘要
From the early non-weldable duplex grades and the more modern 22Cr duplex steels developed in the seventies,a variety of new steels have emerged on the market place with different corrosion resistance and mechanical properties.The process and alloy development is facilitated by the application of thermodynamic databases.The physical metallurgy of stainless steels,in particular the thermodynamic descriptions of phase equilibria and kinetics,is fairly well described at higher temperatures.However when such phenomena as low temperature precipitation of e.g alpha prime in the iron-chromium and higher systems are described,the extrapolation from original assessments is very large.The need of experimental low temperature data is thus crucial and unfortunately limited.Also experimental data is needed to illuminate mechanisms e.g.for the low temperature embrittlement ( 475℃ embrittlement) causing limitations,primarily by the weldment performance,in the upper service temperature of duplex stainless steels.In the presentation examples from high temperature phase transformations as well as attempts to simulate low temperature transformations are given.