Effect Of Abrasive Particle On Impact Wear Behavior Of TC4 And TC17 Titanium Alloy

Titanium alloys were widely used in aviation industry because of their low density,heat resistance,corrosion resistance and good processing performance.Titanium alloys were not only used as structural materials of aircraft,but also used in the fans,compressor discs and blades of aviation engine.Many kinds of working conditions of titanium alloys were affected by impact wear.The engine blades were damaged at high speed would cause huge safety risks to the aerospace vehicle.In this paper,the impact wear tests of TC4 and TC17 titanium alloy under sand condition were carried out based on the modified energy controlled impact wear tester.The impact dynamic response and wear behavior of titanium alloys under sand and no sand conditions were studied.The effects of particle size,sand type,sand proportion,impact times and impact velocity on impact wear behavior of titanium alloys were studied.The main conclusions can be drawn as follows:(1)The sand particles added to the impact interface can significantly affect the wear behavior of materials.Compared with the condition without sand,the impact contact time,energy absorption rate and wear volume of hard sand environment increased significantly,and the peak impact force decreased significantly.(2)Under the condition of soft sand,with the increased of sand particle size,the impact peak value of titanium alloy decreased,the impact contact time increased,the impact energy absorption rate and wear area increased obviously,and the volume of debris accumulation tended to increase.Under the condition of hard sand,the area of wear zone increased with the increase of sand particle size.And the peak impact force,energy absorption and wear depth first increased and then decreased.(3)With the increased of impact times,the peak impact force and impact return velocity decreased significantly,and the wear rate and wear rate increase under different sand proportions.When the proportion of sand particles was 50:50,?negative wear? would occur when the impact times was less than 5000,and ?positive wear? would occur when the impact times was more than 10000.Under pure soft condition,it always showed ?negative wear?.(4)With the increased of impact velocity,the change trend of wear volume and wear rate were different under different sand proportions.When the proportion of sand particles was 50/50,the wear volume changed from "negative" to "positive" with the increased of impact velocity.Under pure soft condition,it always showed negative wear.(5)The wear volume and wear rate increased with the increase of the proportion of hard sand particles.When the proportion was 75/25 or 100/0,the "negative wear" may occur because the soft sand was broken and adhered to the surface of the sample.The peak value of impact force and absorbed energy increased with the increase of impact velocity,while the contact time and energy absorption rate decreased.(6)In the environment without sand particles,the wear mechanism of titanium alloy was mainly delamination wear,and the wear area was obviously oxidized.In the condition of soft sand particles,the wear mechanism of titanium alloy was cutting action and debris accumulation.Under the hard sand environment,the wear mechanism was mainly micro-cutting and extrusion spalling.Under the condition of mixed sand particles,the wear mechanism mainly included cutting,extrusion and spalling of hard sand particles,and soft sand particles breaking to form shells on the surface of the sample.