R180高钒耐磨弯管的凝固数值模拟

Numerical Simulation of Solidification Process of High Vanadium Wear-resistant R180 Bend-pipe

采用Pro-CAST软件对R180弯管三维建模,基于铸造工艺参数对弯管内胆凝固过程的温度场、应力-应变场进行耦合数值模拟,并将优化后的铸造工艺应用于试验生产。采用扫描电镜、显微硬度计、冲击试验机、超声波探测仪等手段,研究了模拟优化后的铸造工艺参数对铸造缺陷和碳化物析出的改善作用。结果表明,将钢液冷却至200℃以下,最大等效应力为128 MPa,较大缩孔出现在铸件与冒口、浇铸口交汇处;铸件中铸造缺陷少,组织均匀,碳化物分布均匀。

The three-dimensional modeling of R180 pipe bend inner bladder was established by Pro-CAST software,coupling numerical simulation of temperature field and stress-strain field in the solidification process of the pipe bend based on casting process parameters were carried out,and the optimized casting process parameters were applied to test production.The improvement of casting defects and carbide precipitation by optimization of casting process parameters with numerical simulation were investigated by the scanning electron microscope,the microhardness instrument,the impact testing machine,the ultrasonic depth finder and other methods.The results show that the maximum effective stress is128 MPa when cooling the molten steels to below 200 ℃.The large shrinkage cavity appears at the intersection of casting,risers and pouring gating.The casting defects are less,and more uniform microstructure and carbide distribution.