42CrMo模铸钢锭凝固场数值仿真与超声检测分析

采用大型商业软件ProCAST建立了钢锭凝固传热数值仿真，钢锭模在凝固过程中的温度场是空间和时间的变化量，属于三维不稳定态传热。为了验证钢锭凝固过程温度场变化对钢锭冶金缺陷的影响，本文采用24寸42CrMo钢种钢锭模进行数值仿真。采取钢锭浇注过热度、断面温度梯度、液相线和固相线的分析，模拟了钢锭凝固过程中温度场、凝固分数、缩松率及Niyama的分布。通过仿真与实际操作工艺相结合，以及钢锭的超声检测和解剖验证的低倍检验，证明了仿真技术和超声检测可以提高钢锭的冶金质量。

Numerical simulation and ultrasonic testing analysis of solidification field of 42CrMo ingot

The commercial software ProCAST was used to establish the numerical simulation of heat transfer in ingot solidification. The temperature field of ingot mold in solidification was the variable of space and time, which belonged to three-dimensional unsteady heat transfer. In order to verify the influence of temperature field change on the metallurgical defects of ingot in solidification process, the 24-inch ingot mold made of 42CrMo steel was selected for numerical simulation. The temperature field, solidification fraction, shrinkage porosity and Niyama distribution in ingot solidification were simulated by analyzing the superheat degree of ingot pouring, temperature gradient in cross section, liquidus and solidus. Through the combination of simulation and actual operation process, as well as the ultrasonic testing and macroscopic inspection of anatomical verification of ingot, it was proved that the simulation technology and ultrasonic testing could improve the metallurgical quality of ingot.