金属凹模中半埋藏环形裂纹电磁热止裂的数值模拟  

Numerical Simulation of Cracking Prevention by Electromagnetic Heating for the Half-Embedded Looped Crack of the Metal Matrix

作　　者：郑丽娟[1] 付宇明[1] 白象忠[1] 

机构地区：[1]燕山大学,河北秦皇岛066004

出　　处：《模具工业》2003年第10期6-9,共4页Die & Mould Industry

基　　金：国家自然科学基金资助项目 (50275128) ;河北省自然科学基金资助项目 (599255)

摘　　要：采用有限元方法研究了带半埋藏环形裂纹的Cr12MoV圆筒形凹模的电磁热止裂问题 ,建立了超强脉冲电流放电瞬间 ,环形裂纹尖端附近电场、温度场和热应力场的藕合关系。数值模拟分成热—电藕合 (焦耳热问题 )和热—机械藕合两个过程来实现 ,通过数值解析轴对称模型 ,给出了脉冲放电瞬间Cr12MoV凹模中电流—温度—热应力的求解过程 ,得到了脉冲放电瞬间带半埋藏环形裂纹凹模的温度场和热应力场。Cracking Prevention for the semi-embedded looped crack in the cylindrical Cr12MoV matrix by electromagnetic heating was studied with the finite element method. The coupling relationship between the electric, temperature and thermal stress fields close to the tip of the looped crack at the extra-strong impulse current discharging moment was built up. The numerical simulation was realized by two processes of thermal-electrical coupling (Joule heat) and thermal-mechanical coupling. Through numerical analysis of the axis-symmetric model, the resolving process for the current-temperature-thermal stress of the Cr12MoV matrix at the discharging moment was deduced and the temperature field and thermal stress field of the matrix with a semi-embedded looped crack at the impulse discharging moment were obtained.

关 键 词：环形裂纹 止裂 电磁热效应 温度场 热应力场 

分 类 号：O482.6[理学—固体物理] O346.1[理学—物理]