Surface Morphology And Cold Bending Properties Study Of Hot Rolled Titanium Plate By EPS Sand-blasting Process

Titanium alloys are commonly used in aerospace and marine engineering.During the hot forming process,titanium alloy will form a layer of oxide skin on the surface,which will affect the processing performance of the titanium alloy,or even damage the processing equipment.At present,pickling is a common descale process,while it will cause serious environmental pollution.Considering that the pollution caused by pickling,the EPS sand-blasting process is an efficient surface technology which is environmentally friend.Nowadays,the EPS sand-blasting technology is mainly applied to the steel plate descaling.Herein,our study is focused on the titanium plate descaling by EPS sand-blasting technology.In this paper,two typical titanium alloys TC4 and TA1 are used to EPS sand-blasting and bending test.The effect of EPS sand-blasting on the surface morphology,microstructure,surface micro hardness and cold bending properties of TC4 and TA1 hot rolled titanium plates are studied for exploring the best EPS sand-blasting technology to provide theoretical guidance in practical production.The main conclusions are as follows:(1)The EPS sand-blasting technology can effectively remove the oxide skin on the surface of the hot rolled titanium plate.However,due to the impact of sand-blasting,cracks,pits,peeling and other defects appear on the surface of the sample.Moreover,with the increase of sandblasting times,the surface damage of titanium plate increases,and the cold bending property of titanium material becomes worse.(2)The hardened layer on the surface of TC4 hot rolled titanium plate is caused by solid solution strengthening of oxygen element,while the hardened layer on the surface of TA1 is caused by sand-blasting strengthening.The EPS sandblasting process can effectively remove the oxide skin on the surface,but it cannot remove the surface oxygen rich layer of TC4 titanium plate.The existence of oxygen rich layer will lead to the decrease of cold bending properties of materials.(3)The surface damage of TC4 titanium plate with 4 times EPS sand-blasting is the smallest,resulted a better cold bending property.The cold bending properties of TA1 samples with different EPS sand-blasting technology can reach the standard of use.The EPS sand blasting technology is a kind of environmentally friendly descaling technology which can instead of pickling for TA1 titanium plate.