Analysis of Deformation Features of Titanium Alloy Waste during Briquetting under Hydrogen Plasticization Conditions

The article presents an analysis of the application features of the hydrogen plasticization effect during cold briquetting of titanium chips and subsequent thermocompression processing of the briquettes. The expediency of hydrogenation of the material of already formed briquettes, rather than of the loose mass of chip waste, has been established. Due to the developed surface of the chip objects and the small thickness of the fractions, the effect of hydrogen plasticization is maximal, which allows for thermocompression processing at relatively low temperatures. Rational concentrations of material saturation with hydrogen, which ensure the greatest effect of hydrogen plasticization for various grades of titanium alloys, have been found. In particular, the optimal range of hydrogen saturation for the VT3-1 alloy is 0.50–0.75 wt %, for the VT6 alloy 0.38–0.50 wt %, for the VT20 alloy 0.40–0.65 wt %. It has been established that when processing chips of titanium alloys of grades VT3-1, VT6, VT20, the use of the thermocompression treatment operation and the effect of hydrogen plasticization allows not only to increase the average relative density of the briquette from ρrel = 0.79–0.84 to ρrel = 0.92–0.93, but also promotes the appearance and growth of centers of solid-phase bonding between the fractions of titanium chips already at the stage of thermocompression of the briquette. The recommended rational technological parameters of the thermocompression treatment process, ensuring sufficient compaction of the briquette, have the following values: temperature range of ∼400–450°C, holding time of ∼4.0–4.5 h, specific force (pressure) of thermocompression of ∼600–650 MPa