Open AccessStudy of the structural state of the metal welded joint 2.25Cr-1Mo-V steel depending on the parameters of post-weld heat treatment
Author(s) -
T. I. Titova,
Natalya A. Shulgan,
A. S. Borovskoy
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/826/1/012016
Subject(s) - welding , bainite , materials science , metallurgy , joint (building) , carbide , brittleness , composite material , vickers hardness test , microstructure , austenite , structural engineering , engineering
The results of studies of the structural state and properties of welded joints of steel 2.25Cr-1Mo-V after various modes of post-weld heat treatment are presented. The study of all zones of the welded joint using an optical microscope at magnifications up to 1000 times was conducted. It was established that the structure of the weld metal and HAZ of the welded joint 2.25Cr-1Mo-V steel in all thermal conditions is represented by bainite with different contents and distribution of the carbide phase. The level of hardness of the welded joint in Vickers units according to ASTM E92 is studied. The following critical values of the Larsen-Miller parameter were determined: for which the weld metal and HAZ ensure the absence of brittle structures with hardness higher than 350 HV10, exposed to hydrogen and the formation of cold cracks, at which the required level of hardness for trouble-free operation is not more than 248 HV10 and at which the coagulation of carbides is too intense and leads to a decrease strength properties.