模具沉积层应变的模拟

为分析沉积层应变的变化情况，并找出温度与形变的变化规律，采用有限元分析软件ANSYS计算并绘制不同时刻以及不同位置沉积层内的温度及应力应变曲线，在建立传热模型过程中考虑了金属液滴向沉积层的传热以及沉积层向系统外的热量散失等问题．采用在厚度方向以微小层逐层叠加来模拟涂层的增厚，并以此为基础构造沉积层有限元计算模型，应用单元生与死逐层激活层单元参与计算过程．实现移动边界以充分模拟真实的喷涂沉积过程．通过分析不同时刻以及不同位置沉积层内的应力应变曲线，获得了沉积层应力应变变化规律．结果表明，沉积层内存在残余塑性应变，且沉积层与母模接触部位等效应力最大，是最易翘曲的地方，验证了沉积层失稳的一般形式．

Simulation and Discussion of Mold Deposit Strain

In order to analyze the strain field of the deposit, and to identify the changes of temperature and deformation, the ANSYS software was used for the curves of temperature and stress-strain curves at different times and different locations in the deposit. The transfer of heat and mass from metal spray to coating and the heat loss by radiation were taken into ac- count when the mathematical model was put forward. The geometry model was built through the micro-thickness increase of the coatings. In the model, the micro-thickness lamellas were activated gradually to participate in the calculation. Movable boundary condition was used to simulate the practical deposition process. By analyzing the stress-strain curves at different times and different locations in the deposit, we Obtained stress-strain variation of deposit. The results show that the residual plastic strain exist in the deposit, and maximum equivalent stress exist in contact area between deposit and mold, where is the most vulnerable to warping, verify the general form of deposit instability.