基于Fluent的钛合金激光氮化机理及数值模拟  

Mechanism of Titanium Laser Nitriding and Numerical Simulation Based on Fluent

作　　者：赵辉[1] 许京荆[1] 陈志磊[2] 张永彬[2] 

机构地区：[1]上海大学机电工程与自动化学院,上海200072 [2]表面物理与化学重点实验室,四川绵阳621907

出　　处：《材料科学与工程学报》2016年第6期1004-1009,共6页Journal of Materials Science and Engineering

基　　金：中国工程物理研究院科学技术发展基金资助项目(9090701)

摘　　要：基于非等温产生的表面张力梯度导致熔池区域内的马兰戈尼对流对激光氮化传热和传质过程有重大的影响。本文采用计算流体软件Fluent对钛的激光氮化过程进行探究和重现,结合传热过程中材料温升引起的相变模型及流体体积函数(VOF)模型分析气—液降膜传质机理,通过建立瞬态激光氮化温度场和浓度场的耦合模型,对激光氮化过程的传热,熔池流动和传质机理进行数值模拟。分析结果给出了钛工件的熔池形成、内部流动、氮化层的氮含量及其分布与激光参数之间的关系,为激光氮化工艺参数优化提供了理论依据。Based on the major effect of Marangoni convection of molten pool region produced of nonisothermal surface tension gradient on the progress of heat transfer and mass transport of laser nitriding,the study on the mechanism of titanium laser nitriding is described using fluid dynamic analysis technique of FLUENT program.The progress of gas-liquid falling film desorption is presented by combining phase-change model with fluid volume function（VOF）model.According to the transient coupled model of temperature field and concentration field,the laser nitriding process involving heat transfer,fluid flow and mass transport is simulated.The relationships among forming of melt pool of titanium workpiece,internal flow,content and distribution of nitrogen in nitrided layer and laser parameters are expressed.The mechanism and used methods can be applied for parameter optimization of laser nitriding process.

关 键 词：激光氮化 马兰戈尼对流 传热传质 数值模拟 VOF 

分 类 号：TG17[金属学及工艺—金属表面处理]