Yıldıran Avcu Yasemin, Yetik Okan, Guney Mert, Iakovakis Eleftherios, Sınmazçelik Tamer, Avcu Egemen
Department of Mechanical Engineering, Kocaeli University, Kocaeli 41001, Turkey.
School of Materials, The University of Manchester, Manchester M13 9PL, UK.
Materials (Basel). 2020 Sep 30;13(19):4363. doi: 10.3390/ma13194363.
Ti6Al4V alloy was shot peened by using stainless-steel shots with different sizes (0.09-0.14 mm (S10) and 0.7-1.0 mm (S60)) for two durations (5 and 15 min) using a custom-designed peening system. The shot size was the main parameter modifying the roughness (0.74 µm for S10 vs. 2.27 µm for S60), whereas a higher peening time slightly increased roughness. Hardness improved up to approximately 35% by peening with large shots, while peening time was insignificant in hardness improvement. However, longer peening duration with large shots led to an unwanted formation of micro-cracks and delamination on the peened surfaces. After dry sliding wear tests, the mass loss of peened samples (S60 for 15 min) was 25% higher than that of un-peened samples, while the coefficient of friction decreased by 12%. Plastically deformed regions and micro-scratches were observed on the worn surfaces, which corresponds to mostly adhesive and abrasive wear mechanisms. The present study sheds light on how surface, subsurface and tribological properties of Ti6Al4V vary with shot peening and peening parameters, which paves the way for the understanding of the mechanical, surface, and tribological behavior of shot peened Ti6Al4V used in both aerospace and biomedical applications.
使用定制设计的喷丸系统，采用不同尺寸（0.09 - 0.14毫米（S10）和0.7 - 1.0毫米（S60））的不锈钢丸对Ti6Al4V合金进行喷丸处理，持续时间为两个（5分钟和15分钟）。喷丸尺寸是改变粗糙度的主要参数（S10为0.74微米，S60为2.27微米），而较长的喷丸时间会略微增加粗糙度。使用大尺寸丸粒喷丸可使硬度提高约35%，而喷丸时间对硬度提高影响不大。然而，使用大尺寸丸粒进行较长时间的喷丸会导致喷丸表面出现不希望的微裂纹和分层。干滑动磨损试验后，喷丸样品（S60，15分钟）的质量损失比未喷丸样品高25%，而摩擦系数降低了12%。在磨损表面观察到塑性变形区域和微划痕，这主要对应粘着磨损和磨粒磨损机制。本研究揭示了Ti6Al4V的表面、亚表面和摩擦学性能如何随喷丸及喷丸参数变化，为理解航空航天和生物医学应用中喷丸处理的Ti6Al4V的力学、表面和摩擦学行为铺平了道路。
