Based On Hot Rolling Ring Forming Thermal Physical Properties Of As-cast 42 Crmo Steel Research

With the development of industrial technology in these years, the large ringparts have been widely used in various fields of different trades, whichespecially play an important role in machine manufacturing and materialsprocessing. The article bases on NSFC project and mainly study thethermal-physical characteristic of casting42CrMo steel which is directly used inhot ring rolling. They can provide material model for numerical simulation ofhot ring rolling process, and also have guiding significance to actual production.To the casting42CrMo used in hot ring rolling, the paper aims to simulateits three important thermal-physical characteristic parameter curves(such asthermal conductivity, specific heat, thermal diffusivity) which change withtemperature at high temperature(500～1200℃) through the soft of JMatPro, andmeasure thermal-physical characteristics data at8point(every100℃for onepoint) at the same temperature range by using laser thermal conductivitymeter(LFA427), then utilize the soft of Origin to make the fitting curve.Comparing with two curves above, we can get the thermal-physicalcharacteristic curves of casting42CrMo steel which is closed to the real mostly.The data above can provide the following numerical simulation of ring rollingprocess with reliable technological parameter and material model.In this paper the main achievement are listed as follow: Simulatethermal-physical characteristic of casting42CrMo steel through the soft ofJMatPro to gain the change rules of these thermal-physical characteristics above in hot ring rolling, and the factors which affect thermal-physical characteristics:temperature, size of grain, microstructure transformation and percentagecomposition of microelement (Cr, Mn, Mo), uncover the reasons why the factorsabove make the change; Measure thermal-physical characteristics data of casting42CrMo steel by using laser thermal conductivity meter firstly; Comparing withtwo curves above, prove whether the results of simulation are true according toexperiment results, and we can get the thermal-physical characteristic curves ofcasting42CrMo steel which is closed to the real mostly; Put thethermal-physical characteristics curves of casting42CrMo steel into the soft ofDEFORM-3D, then build the material model of this kind of material.