相似理论在焊接温度场和应力场及应变场中的应用

Application of Similitude Principles to Study in Welding Temperature,Strain and Stress Fields

从焊接热效应为焊接残余应力和残余变形的根本原因出发 ,认为相似温度场是相似应力场及应变场的前提。利用因次分析法 ,忽略弹、塑性形变能及相变引起的能量变化 ,推导出焊接温度场相似应满足的条件。在此基础上 ,利用方程分析法导出应力场及应变场的对应关系。为了进行数值验证 ,还推导出为满足相似温度场高斯热源应具备的必要条件。为了表明所推导相似条件的可行性 ,本论文利用平板表面堆焊的数值模拟进行验证 ,得到较好的结果。

In this paper the similitude temperature field is considered as prerequisite to the similitude stress and strain fields because welding heat effect is the essential reason for residual strain and stress.The similitude principles for welding temperature field are deduced by dimensional analysis method.On the basis of similitude temperature field,the correspondence relationship between stress and strain fields is deduced by equatioanl analysis method.The essential conditions of Gauss heat resource for similitude temperature field are also deduced for numerical simulation.In this paper plates with surfacing welding are simulated by numerical method to testify feasibility of the deduced similitude principles and the results show satisfactory coincidences.