热挤压对喷射成形GCr15轴承钢组织和性能的影响

摘要

The GCr15 bearing steel was prepared by spray forming technology.The initial microstructure and the effects of subsequent hot extrusion on the microstructures and mechanical properties of the GCr15 bearing steel were studied.The results show that the structure of spray formed GCr15 bearing steel is equiaxed grain and homogeneous structure and there is no dendrite segregation structure;Due to the characteristics of spray deposition process,there are a large number of micro-porosity defects in the alloy matrix.When the temperature reaches 650℃,the elastic modulus of GCr15 steel after hot extrusion rises to 6520 GPa,which indicates that hot extrusion process can effectively eliminate the porosity defect.%采用喷射成形工艺制备了GCr15轴承钢,研究了热挤压工艺对喷射成形GCr15的显微组织和力学性能的影响.结果表明,喷射成形GCr15轴承钢得到的组织是等轴晶粒和细小的碳化物,基体中不存在枝晶偏析;GCr15沉积坯经过热挤压致密化后,改善了GCr15钢的显微疏松的缺陷,合金力学性能显著提高;当温度达到650oC时弹性模量达到最大值6520 GPa,表明热挤压工艺可有效消除疏松缺陷,从而充分发挥喷射沉积工艺的优越性.