Szwajka Krzysztof, Zielińska-Szwajka Joanna, Trzepieciński Tomasz
Faculty of Mechanics and Technology, Department of Integrated Design and Tribology Systems, Rzeszow University of Technology, ul. Kwiatkowskiego 4, 37-450 Stalowa Wola, Poland.
Faculty of Mechanics and Technology, Department of Component Manufacturing and Production Organization, Rzeszow University of Technology, ul. Kwiatkowskiego 4, 37-450 Stalowa Wola, Poland.
Materials (Basel). 2023 Apr 28;16(9):3460. doi: 10.3390/ma16093460.
Bioimplants should meet important surface integrity criteria, with the main goal of the manufacturing process to improve wear and corrosion resistance properties. This requires a special approach at the cutting stage. During this research, the impact of the cutting parameters on improving the surface integrity of AISI 316L steel was evaluated. In this context of bioimplant applications, the mean roughness Sa value was obtained in the range of 0.73-4.19 μm. On the basis of the results obtained, a significant effect was observed of both the cutting speed and the feed rate on changes in the microstructure of the near-surface layer. At a cutting speed of 150 m/min, the average grain size was approximately 31 μm. By increasing the cutting speed to 200 m/min, the average grain size increased to approximately 52 μm. The basic austenitic microstructure of AISI 316L steel with typical precipitation of carbides on the grain boundaries was refined at the near-surface layer after the machining process. Changing the cutting speed determined the hardness of the treated and near-surface layers. The maximum value of hardness is reached at a depth of 20 μm and decreases with the depth of measurement. It was also noted that at a depth of up to 240 μm, the maximum hardness of 270-305 HV1 was reached, hence the height of the machining impact zone can be determined, which is approximately 240 μm for almost all machining conditions.
生物植入物应满足重要的表面完整性标准，制造过程的主要目标是提高耐磨性和耐腐蚀性。这在切削阶段需要一种特殊的方法。在本研究中，评估了切削参数对改善AISI 316L钢表面完整性的影响。在生物植入物应用的背景下，平均粗糙度Sa值在0.73 - 4.19μm范围内获得。基于所得结果，观察到切削速度和进给速度对近表层微观结构变化均有显著影响。在切削速度为150 m/min时，平均晶粒尺寸约为31μm。将切削速度提高到200 m/min时，平均晶粒尺寸增加到约52μm。加工过程后，AISI 316L钢具有典型晶界碳化物析出的基本奥氏体微观结构在近表层得到细化。改变切削速度决定了处理层和近表层的硬度。硬度最大值在20μm深度处达到，并随测量深度减小。还注意到，在深度达240μm时，达到了270 - 305 HV1的最大硬度，因此可以确定加工影响区的高度，对于几乎所有加工条件，该高度约为240μm。
