Shark-Skin-Inspired Micro-Riblets Forming Mechanism of TC17 Titanium Alloy with Belt Grinding

Abstract

Belt grinding could improve the surface integrity of titanium alloys, but it is difficult to achieve breakthroughs in the grinding mechanism due to the lack of grinding mechanism of titanium alloy micro-riblets structure. The characteristics of micro-riblets structure are discussed, and the belt grinding method for the micro-riblets is proposed based on the structural features. On this basis, the corresponding relationship model between the belt grinding and the surface parameters of the micro-riblets structure is established. The standard experimental platform was built and the belt grinding experiment was completed. The typical structural characteristics based on the method were obtained. The influence of the belt grinding process parameters on the formation of micro-riblets structures was analyzed. The results show that the micro-riblets structure achieved by the belt grinding method is dominated by sawtooth riblets. The width of the trench ( s) is between 2.5μ m and 8μ m , the average value is 4.91μ m , the height of the trench ( h ) is between 3.5μ m and 9μ m , the average value is 5.91μ m , and the angle of the trench ( α ) is between 28° and 68°, the average is 42.3°. At the same time, it can be seen that increasing the grinding positive pressure ( F-n ), the feed step ( P ), and reducing the grinding feed rate ( vp ) can increase the sawtooth riblets width ( s ), the groove height ( h ), and the trench angle ( α ) of the micro-riblets structure surface. It can also increase the surface of the micro-riblets structure surface sawtooth riblets b1 , b2. Moreover, the groove ratio h/s and the groove bearing side length ratio b1/b2 have a sinusoidal fluctuation tendency, and the ratio mainly jumps up and down at a fixed value.