预应力加载条件下零件干磨削表面强化层特征

采用预应力复合干磨削加工技术,对未调质45#钢试件在不同预应力加载条件下实施表面磨削淬硬,观测不同磨削深度和进给速度条件下的试件表层金相组织,测量并分析试件在不同预应力条件下磨削淬硬层厚度、金相组织的变化状况,并通过试件截面不同位置硬度测定显示淬硬层厚度及金相成分的变化,得到试件施加预应力对淬硬强化层厚度的影响规律.研究表明,预应力淬硬磨削能使工件表面产生强化层,且大的磨削深度和小的进给速度有利于试件表面发生相变强化以及表层塑性变形的增大.

Characteristics of Dry Grinding Surface Hardening Layer Under Pre-stressed Loading Conditions

The surface grinding hardening of non-quenched and tempered 45^# steel specimens under different pre-stressed loading conditions was carried out by using the pre-stressed hardening grinding process (PSHG). The metallographic structures of the specimens surface under different grinding depths and feed rates were observed， and the thickness of the hardening layer of the specimens and the change of its metallographic structure were measured and analyzed under different pre-stressed conditions. The influence of pre-stress on the thickness of the hardening layer was obtained by measuring the hardness of the specimens section. It was shown that the pre-stressed hardening grinding can make the workpiece surface become a hardening layer， and the larger grinding depth and the lower feed rate will be beneficial to the phase transformation hardening and plastic deformation of the surface layer.