压铸模的功能梯度材料涂层性能分析

为了提高压铸模的使用寿命，用有限元方法对涂层为功能梯度材料的压铸模进行分析.梯度材料涂层分为5层，沿模具表面法向氮化钛所占的比例逐渐增加,分别为20%、40%、60%、80%、100%.在不同厚度涂层的应力分析中，涂层中氮化钛的比例不变，只增加每一层的厚度，涂层总厚度分别为0.002 mm,0.004 mm,0.006 mm,0.008 mm,0.01 mm.功能梯度材料的性能参数采用简单混合物运算法则计算.应用有限元法对有功能梯度材料涂层的模具和没有功能梯度材料涂层模具的温度场、应力场进行比较分析，并对不同厚度功能梯度材料涂层的应力进行研究.结果显示:当功能梯度材料涂层的厚度为0.006 mm时温度场分布更合理，表面剪应力及压应力变化平缓，有效延长了模具寿命.

Performance analysis of die casting mold with functionally graded material coating

To prolong the life of die casting model,a finite element method was used to analyze the performance of die casting model with functionally graded material coating.The coating was divided into 5layers.The ratio of titanium nitride was increased gradually along the surface normal of die casting model;the ratio of titanium nitride in each layer was 20%,40%,60%,80%,100%respectively.When the stress of coatings with different thickness was analyzed,the ratio of titanium nitride was invariant,but the thickness of each layer was increased by 0.002mm,0.004mm,0.006mm 0.008mm,0.01mm.The parameter of functionally graded material was calculated by simple arithmetic method.The temperature field and the stress field of die casting model with functionally graded material and without functionally graded material were studied comparatively,and the stress of different thickness of the coating was analyzed.It was found that the temperature field distribution of die casting mold with functionally graded material coating is more reasonable,and the shear stress and the compression stress of die casting model change smoothly,which extends the life of die casting mold when the thickness of functional gradient material coating is 0.006mm.