Experimental study on the high-speed impact of a sand particle on Ti–6Al–4V

Abstract

When sand is ingested by a helicopter engine, it collides with the compressor blades at a high relative speed, causing severe erosion damage. A test was conducted on the high-speed impact of sand particles on the target of Ti–6Al–4 V alloy to enhance the understanding of high-speed impact damage mechanism. The test apparatus was used to create supersonic airflow, which was produced by normal temperature air flowing through a special Laval nozzle. The supersonic airflow produced the drag force to increase the velocity of sand particles up to about 400 m/s. The experiment demonstrated that fractured sand particle caused less damage than nonfractured particle under similar impact conditions. The nonfractured particle directly cut the target more easily than the fractured at a relatively low impact velocity. When the impact speed exceeded 300 m/s, the crater depth increased exponentially with the increase of velocity. Impact angle determined the mode of material failure.