【作者】 史丽婷； 于敦吉； 石守稳； 张喆； 陈旭；

【Author】 Shi Liting;Shi Shouwen;Yu Dunji;Zhang Zhe;Chen Xu;School of Chemical Engineering and Technology,Tianjin University;

【机构】 天津大学化工学院；

【摘要】 316LN奥氏体不锈钢在500℃长期热老化过程中,在晶界处产生了长条状的碳化产物。且随着老化时间的增长碳化物逐渐增多。之后从单拉性能及棘轮疲劳行为两方面研究了热老化对316LN不锈钢机械性能的影响,并从微观角度解释了热老化导致机械性能改变的原因。结果表明,热老化对316LN不锈钢的屈服强度和抗拉强度无影响,但是延伸率会随着老化时间的增长而降低。其次,由于老化后试样塑性降低且表面碳化物的增多,导致塑性应变累积增大,从而增大棘轮应变,降低棘轮疲劳寿命。更多还原

【Abstract】 During the 500 ℃ long-term aging process of 316 LN austenitic stainless steel,long strip of carbide products were produced at the grain boundary.With the increase of aging time,the number of carbide products increased.After that,the effect of thermal aging on the mechanical properties of 316 LN stainless steel was studied from two aspects of uniaxial tensile property and ratcheting fatigue behavior and the reasons for the change of mechanical properties caused by thermal aging were explained from the microscopic point of view.The results show that the thermal aging has no effect on the yield strength and tensile strength of 316 LN stainless steel,but the elongation decreases with the increase of aging time.Secondly,due to the decrease of plasticity and increase of the carbide,the plastic strain increase which increases the ratcheting strain and reduces the fatigue life.更多还原