The Research On The Resistance Of The Cavitation Performance Of Pure Titanium And TC4Titanium Alloy

As early as in1985, people have found the cavitation erosion phenomenon in thefluid machine, the cavitation erosion damage can affect the life of the materialseriously. Cavitation is involved in many other areas such as the ship, hydraulic,machine, chemistry, power generation, and biomedical. Titanium and titanium alloyhave been widely used in those areas. However, the research on the cavitation erosionbehavior of pure titanium and TC4titanium alloy is very less. Due to the low hardness,the anti-cavitation performance of pure titanium and TC4titanium alloy is not good,therefore, how to effectively improve the anti-cavitation performance of pure titaniumand TC4titanium alloy is an urgent problem to solve.In this paper, we used the ultrasonic cavitation testing machine to simulate thecavitation process, and examined the cumulative loss, microstructure, surfaceappearance, hardness during the cavitation erosion. In the experiment, we used theboriding and ion implantation surface treatment to improve the anti-cavitationperformance of pure titanium and TC4titanium alloy, on the basis of optimization ofprocess to discuss the mechanism of cavitation. The experimental results show that:(1)The results show that the cumulative weight loss of TC4titanium alloy is lowerthan pure titanium, TC4titanium alloy has better anti-cavitation performance thanpure titanium.(2)After treating the pure titanium and TC4titanium alloy in different temperaturesand time,we got a biphasic borided layer on the surface of the material. The boridedlayer and the substrate is metallurgical bonding, the surface hardness is significantlyimproved. In the cavitation, the weight loss is very low even after8h and the samplesurface is not completely off after8h. The borided layer plays a good protectionagainst cavitation destruction.(3)After the Nb ion implantation surface modification, the hardness of the surface hasbeen improved for50%and the cavitation erosion-resistance of the material has alsobeen improved. But the ion implantation layer is very thin (nearly100nm). Alongwith the increase of the time, the ion implantation layer will fall off completely until8h, and the cavitation erosion will be accelerated.