冷挤压高强钢抗疲劳性能研究

Anti Fatigue Performance of Cold Extruded High Strength Steel

采用车削加工和冷挤压的方法,对Q460高强度钢的内螺纹进行机械加工,研究了两种机械加工工艺下的内螺纹的表面组织和抗疲劳性能,并对疲劳断口形貌进行了观察。结果表明,经过冷挤压加工后的螺牙区域的晶粒尺寸相对车削加工更为细小;当最大载荷为150 k N和125 k N时,经过车削加工的内螺纹的疲劳寿命都要比经过冷挤压加工的内螺纹疲劳寿命低;经过冷挤压加工得到的内螺纹的疲劳寿命远大于经过车削加工得到的内螺纹,主要与表面加工质量和螺牙内部组织形态与形变有关。

Using turning and cold extrusion method,the internal thread of Q460 high strength steel was machined,the surface microstructure and fatigue resistance of the internal thread were researched under the two kinds of processing method,and the fatigue fracture morphology was observed.The results show that,after cold extrusion,the grain size of thread region is relatively small compared with turning processing method.When the maximum load of 150 k N and 125 k N,the fatigue life of the internal thread through cold extrusion processing is much larger than that through turning processing,which is mainly related to the surface quality and internal thread microstructure morphology and deformation.