Kunčická Lenka, Kocich Radim, Benč Marek, Dvořák Jiří
Institute of Physics of Materials, Czech Academy of Sciences, Žižkova 22, 61600 Brno, Czech Republic.
Faculty of Materials Science and Technology, VŠB-Technical University of Ostrava, 17. listopadu 2172/15, 70800 Ostrava, Czech Republic.
Materials (Basel). 2022 Sep 9;15(18):6291. doi: 10.3390/ma15186291.
The presented work focused on the development of the microstructural and mechanical properties of a AISI 316L stainless steel workpiece prepared through additive manufacturing and subsequently processed by hot rotary swaging. In order to characterize the effects of swaging on the structural development, samples were taken for electron microscopy scanning and microhardness measurements were taken after each swaging reduction. The as-built and final swaged pieces were also subjected to tensile testing at room temperature and at 900 °C. The structural analyses showed that the hot swaging introduced a substructural formation; low angle grain boundaries prevailed over high angle ones after each pass. The swaging also imparted an almost complete elimination of the porosity and significant grain size; the average grain area decreased from the original value of 365.5 µm to 4.4 µm after the final swaging pass. The changes in the texture between the passes were negligible, however, the grain refinement went hand in hand with the microhardness increase (up to almost 300 HV1). The results of the tensile testing confirmed that the mechanical properties of the swaged pieces which improved dramatically and remained favorable up to high temperatures.
所展示的工作聚焦于通过增材制造制备并随后进行热旋锻加工的AISI 316L不锈钢工件的微观结构和力学性能的发展。为了表征旋锻对结构发展的影响，在每次旋锻减径后取样进行电子显微镜扫描，并进行显微硬度测量。所制备的工件和最终旋锻后的工件还在室温及900℃下进行了拉伸试验。结构分析表明，热旋锻引入了亚结构形成；每次旋锻后，低角度晶界比高角度晶界更为普遍。旋锻还几乎完全消除了孔隙率并显著细化了晶粒尺寸；最终旋锻道次后，平均晶粒面积从原始值365.5 µm减小至4.4 µm。道次间织构的变化可忽略不计，然而，晶粒细化与显微硬度增加（高达近300 HV1）同步发生。拉伸试验结果证实，旋锻后工件的力学性能显著改善，并且在高温下仍保持良好。
