New production process of gray iron castings produced by direct ironmaking with water slag iron is introduced. The metallographic analysis and mechanical properties of gray iron castings produced by this method are tested. The lost foam casting process of gray iron castings produced by this process method was studied by using ProCAST software and visual environment software of ESI group. The following conclusions are obtained:
- A new process method for directly producing gray iron lost foam castings by using water slag iron ironmaking has been developed jointly with ZHY casting company. This method can effectively shorten the production cycle, reduce the production cost and improve the production efficiency.
- The metallographic analysis and mechanical property experiment of gray iron castings produced by water slag iron ironmaking were carried out. The experimental results show that the metallographic structure of gray iron castings produced by this method is completely consistent with that of standard gray iron; The tensile strength, flexural strength and compressive strength of HT150 castings produced by this method fully meet the service performance requirements of HT150.
- Then, aiming at the lost foam process of producing gray iron castings by water slag iron ironmaking, the trial production schemes of bottom injection and top injection are put forward, and Pro is used_ The three-dimensional modeling of gray iron castings, gating system and riser is carried out by E software. ProCAST software is used as the numerical simulation tool of lost foam casting process to simulate the filling and solidification process of two trial production schemes of gray iron castings produced by water slag iron. The results show that the two trial production schemes can not solve the problem of significant shrinkage and porosity and achieve good slag discharge and exhaust. By comparing the simulation results with the test results, the thermophysical parameters for accurately calculating the solidification process of the gray iron casting are established.
- According to the structural characteristics and two trial production results of gray iron castings of underframe, an improved scheme of stepped pouring is proposed. The mold filling and solidification process of the improved scheme are simulated by ProCAST. The simulation results show that the stepped pouring scheme can not only solve the problems of significant shrinkage, porosity and slag inclusion of trial products, It can also effectively shorten the time required for the filling process of gray iron castings.
- Through the numerical simulation, metallographic analysis and mechanical property experiment of the lost foam process of directly producing gray iron castings by using water slag iron, it can be seen that using water slag iron to produce gray iron castings can not only meet the performance requirements of gray iron castings, but also greatly save the production cost of enterprises. Using steel-making waste slag as raw material is conducive to sustainable development and construction.