Study on P91 Alloy Ductile Fracture Behavior Based on Compressing Experiment

Abstract

Abstract: Ductile fracture was the main fracture form in plastic processing of metal, and obtained material's critical damage value was the key to numerical simulation of plastic processing, which involved fracture behaviors. Compressing experiments were employed and the complex stress integration in upsetting process was calculated with numerical simulation herein. Under normalized C-L criteria, the critical damage value of P91, a kind of heat resisting & high tensile alloy, was obtained. Based on the calculation results, bottom-cutting process, a preforming process used in seamless steel tube production was simulated. The simulation results agree with the real engineering ones.

Key words: ductile fracture, P91 alloy(9Cr1Mo), compressibility method, bottom-cutting, normalized C-L criteria

摘要： 金属塑性加工中发生的断裂多为韧性断裂，测定材料韧性断裂时的临界损伤值是对切底、冲裁等包含断裂行为的塑性加工过程进行数值模拟的关键。采用压缩法进行了材料试验，并利用数值模拟解决了镦粗过程中应力积分较为复杂的问题，得到了Normalized C-L准则下耐热高强合金P91的临界损伤值，在此基础上，采用单元删除法对P91无缝钢管切底制坯过程进行了模拟，模拟结果与实际工程结果基本吻合。

关键词: 韧性断裂, P91合金（9Cr1Mo）, 压缩法, 切底, 归一化C-L准则

CLC Number:

TG111.91

Liu Yutong, Yuan Chaolong, Wu Rendong, Jiao Wei, Qiang Hao. Study on P91 Alloy Ductile Fracture Behavior Based on Compressing Experiment[J]. China Mechanical Engineering.

刘雨桐, 袁朝龙, 吴任东, 焦玮, 强浩. 基于压缩试验法的P91韧性断裂行为研究[J]. 中国机械工程.

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