汽轮机低压叶片用20Cr13马氏体钢异种钢接头的组织性能分析

Microstructure and mechanical properties of dissimilar welded joints of 20Cr13 martensitic steel for low pressure steam turbine blade without PWHT

对Ni基焊材的20Cr13马氏体耐热钢焊态异种钢接头的组织与力学性能进行了试验研究,分析了此类焊接接头的薄弱部位,提出了工艺改进措施。试验结果表明,焊态异种钢接头的抗拉强度可以达到母材的90%以上,热影响区粗晶区是此类接头的薄弱部位;采用多层多道的小规范焊接工艺并补加焊接回火焊道,可以使20Cr13钢热影响区粗晶区的性能得到改善。

Experimental study on microstructure and mechanical properties of dissimilar steel wel-ded joints of 20Cr13 martensitic heat-resistant steel for steam turbine blade without PWHT were conducted.Moreover,the weak parts of these kinds of j oints were analyzed and process improve-ment measures were proposed.The results show that,the tensile strength of 20Cr13 steel welded joints using Ni base filler metal without PWHT can reach over 90% of parent metal＆#39;s and coarse grain HAZ are weak zone of the welded joints.Multi-pass welding process of low welding heat input and temper bead should be used with the purpose of coarse grain regions＆#39;brittlement reduction.