基于近似原位观测的Cr5合金钢高温杨氏模量及其拉伸细观损伤机理研究  

High-Temperature Young's Modulus and Tensile Meso-Damage Mechanism of Cr5 Alloy Steel Based on Approximate In-Situ Observation

作　　者：陈学文[1] 郭乐乐 刘丙旗 周旭东[1] 司亚辉 白荣忍 CHEN Xuewen;GUO Lele;LIU Bingqi;ZHOU Xudong;SI Yahui;BAI Rongren(School of Materials Science and Engineering,Henan University of Science and Technology,Luoyang,Henan 471023,China)

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471023

出　　处：《昆明理工大学学报（自然科学版）》2022年第6期25-32,42,共9页Journal of Kunming University of Science and Technology(Natural Science)

基　　金：国家重点研发计划项目(2020YFB2008400)。

摘　　要：为研究Cr5合金钢高温成形过程的损伤机理,提出借助位移传感器测量材料高温杨氏模量值和近似高温原位观测试验研究材料高温损伤特性的方法.研究了Cr5合金钢800~1150℃的杨氏模量变化,分析了Cr5合金钢高温拉伸过程的细观损伤行为.结果表明:随着温度的升高,Cr5合金钢高温杨氏模量值急剧下降,1150℃时的杨氏模量值仅35 GPa;Cr5合金钢拉伸试样为韧性断裂,断口表面有大量韧窝,通过试验方法设计获得了材料高温拉伸过程的SEM照片,观察Cr5合金钢高温拉伸过程的SEM照片证明了材料的断裂是因为微小空洞萌生聚集长大、微裂纹延伸扩展造成的,伴随着损伤的发生,材料所能承受的载荷逐渐减小;进行XRD成分检测发现材料空洞和裂纹处的杂质含量高于基体成分,金属内部杂质含量高更易造成材料内部损伤的发生.In order to study the damage mechanism of Cr5 alloy steel during high temperature forming process,this paper proposes a method to measure the high temperature Young's modulus of the material by means of displacement sensor and approximate high temperature in-situ observation test to study the high temperature damage characteristics of the material.The change of Young's modulus of Cr5 alloy steel at 800~1150℃was stud-ied,and the micro-damage behavior of Cr5 alloy steel during high temperature tensile process was analyzed.The results show that with the increase of temperature,the Young's modulus value of Cr5 alloy steel at high temperature decreases sharply,and the Young's modulus value at 1150℃is only 3-5 GPa.The tensile specimen of Cr5 alloy steel is ductile fracture,and there are a lot of dimples on the fracture surface.The plasticity of Cr5 alloy steel increases with the increase of temperature.Observation of SEM photos of Cr5 alloy steel during high temperature tensile process proves that the fracture of the material is caused by the initiation and aggregation of tiny voids and the extension and expansion of microcracks,and the load that the material can withstand gradually decreases with the occurrence of damage.XRD composition detection shows that the impurity content in the voids and cracks of the material is higher than that of the matrix composition,and the high impurity content in the metal is more likely to cause internal damage to the material.

关 键 词：Cr5合金钢 杨氏模量值 静态拉伸 原位观测 细观损伤 

分 类 号：TG142.33[一般工业技术—材料科学与工程]