摘要
本文研究了18-8型奥氏体不锈钢的对称拉压低周疲劳行为特征及动态应变时效(DSA)预处理的影响结果表明:在所使用的应变幅(±0.5%-±1.5%)范围内,试样都经过循环硬化、饱和和循环软化过程,在相同的应变幅下DSA预处理后循环峰值应力高于固溶态及冷变形预处理状态,但疲劳断裂寿命相差不大TEM分析结果表明:材料经DSA预处理后,形成了均匀、高密度、稳定的位错组态是提高循环峰值应力的主要原因,而循环软化则是由于形成了低密度的。
Studies were made of the symmetric tensile-compressive low cyclic fatiguebehaviour and dynamic strain aging (DSA) pre-treatment influenced on 18-8 austeniticstainless steel. Within the tested amplitude range of strain: ±0.5%-±1.5%, the three pro-cesses of cyclic hardening, cyclic saturation and cyclic softening were observed. In the sameamplitude of strain, the peak stress of the samples pre-treated by DSA is higher than that ofsolid-solution and cold working pre-treatment, but almost no differences of the fatigue livesof them were found. TEM observation shows that the uniform and stable dislocation net-works with high density form after DSA pre-treatment, which increases the cyclic peak stress.The cyclic softening is resulted from the low dislocation density and elongated cell structurewith low energy.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
1993年第6期A283-A288,共6页
Acta Metallurgica Sinica
基金
福建省自然科学基金
关键词
奥氏体不锈钢
应变时效
低周疲劳
18-8 austenitic stainless steel
dynamic strain aging
low cycle fatigue
