Open AccessEffect of precipitation under long-term aging at 650 °C on the tensile strength of advanced 10%Cr heat-resistant steel
Author(s) -
Nadezhda Dudova,
Roman Mishnev,
Marina Tikhonova,
Rustam Kaibyshev
Publication year - 2019
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/672/1/012062
Subject(s) - materials science , ultimate tensile strength , microstructure , precipitation , martensite , metallurgy , dispersion (optics) , composite material , creep , precipitation hardening , physics , meteorology , optics
The effect of long-term aging for 10 3 to 3.9·10 4 h at 650 °C on the microstructure, dispersion of secondary phases, and tensile strength properties was studied in a low-nitrogen 10%Cr martensitic steel with 3%Co and 0.008%B additives. Tensile tests of small specimens cut from grip portions of creep tested specimens were carried out at ambient and elevated (650 °C) temperatures. An increase in the yield stress and ultimate tensile strength after 10,000 h of aging was revealed to be associated with the precipitation of V-rich MX carbonitrides, which compensated for the coarsening of the boundary particles and depletion of W and Mo solutes from the ferritic matrix. The effect of changes of the microstructure and dispersion of secondary phases on strengthening of the steel is discussed.