材料科学
应变硬化指数
硬化(计算)
马氏体
复合材料
奥氏体
冶金
极限抗拉强度
碳化物
铁氧体(磁铁)
微观结构
图层(电子)
作者
K.D. Challenger,J. Moteff
出处
期刊:Scripta Metallurgica
[Elsevier]
日期:1972-02-01
卷期号:6 (2): 155-160
被引量:29
标识
DOI:10.1016/0036-9748(72)90268-2
摘要
Stratified tensile tests were performed to quantitatively investigate strain hardening behavior along a dissimilar metal welded joint (DMWJ) with buttering layer of ultra-supercritical turbine rotor. The results show weld region has lower tensile strength but better strain hardening capacity than base metals (BMs). The buttering layer (BL) exhibits higher strain hardening capacity than weld metal (WM). Two strain hardening exponents were found based on the fitted stress-strain curves using Hollomon equation. The lower exponent is related to the ferrite matrix, whereas the larger exponent is related to the precipitation phase, including martensite, bainite and sorbite. The gradient distribution of strain hardening exponent in heat affected zones (HAZs) is related to the gradient change of tempered martensite and grain size. The strain hardening mismatch in interface is related to the drastic changes in microstructure and amount of carbides. The dislocation cell structure and sub grain were observed after tensile tests, and carbides were elastic during tensile deformation. Kocks–Mecking (K–M) type plots of strain hardening rate versus true stress presented two hardening stages (stages III and IV) in welded joint. More ferrite and finer tempered martensite are conductive to extending the strain hardening period. Local strain hardening parameters play an important role in the accurate evaluation of crack behavior in HAZ and interface.
科研通智能强力驱动
Strongly Powered by AbleSci AI