Abstract: In this paper, 45# steel supports prepared by liquid forging showed excellent performances and the effects of processing techniques on the development of microstructures and mechanical properties of these steel supports were researched. The liquid forging process was simulated and technological parameters were optimized via a ProCAST simulation software. The solidification time, temperature distribution, first principal stress distribution of the 45# steel supports varied with time, temperatures, and position. Two principal parameters, pouring temperature and dwell time, were assessed for their effects on microstructures, mechanical properties, and wear resistance properties of 45# steel supports. Results showed that the optimal pouring temperature of the molten metal and the pressure-holding time were between 1540 °C and 1560 °C and between 35 s and 40 s, respectively. The microstructure, mechanical properties, and fracture behavior of different positions in the support were also discussed, and the central position performed better than the edge because of plastic deformation. Finally, the dynamic solidification process was also investigated and the liquid forging process of 45# steel supports was complex and contained some special metal liquid convection and several plastic deformation stages.

45#钢支座的液态模锻制备工艺及组织性能分析

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