【摘要】 在分析了预置式激光表面熔覆边界传热特点的基础之上,建立了简化的三维温度场分析模型,模拟激光熔覆模压预置层时工件的瞬态温度场;同时,在温度场模拟的基础上提出了以界面定点热循环曲线的最高温度达到特定金属的熔点作为判断预置层与基体间形成良好冶金结合的标准,并依据此标准预测了预置式激光表面熔覆时的工艺参数范围。结果表明,模拟预测的工艺参数范围与实际加工的最佳参数较为接近,对预置式激光表面熔覆的工艺参数选择具有指导意义。更多还原

【Abstract】 Based on the analysis of heat transfer in pre-coated layer for laser cladding, a simple three dimensional model was built up to simulate the transient temperature field in workpiece under different parameters.A criterion that is whether the peak of thermal cycle of some special points at interface reaches melting point of certain element is proposed,and this criterion is used to estimate whether the pre-coated layer is bound to substrate metallurgically and predict the range of processing parameters in laser cladding.The optimal range of processing parameters predicted from simulation is agreement with the results obtained from experiments,which proves that this method of simulation is feasible and can be used to predict processing parameters in pre-coated laser cladding.更多还原