Reducing titanium alloy forgings surface oxidation method!

2022-01-25

The effective method of less oxidation and no oxidation of titanium alloy die forging blank during heating is an important direction to improve metal utilization rate and reduce product cost. The billet of bT3-1 titanium alloy was used in the study. The billet was stripped bare before forging and heated to 950℃ ~ 980℃ in an electric furnace. The sheet samples of BT20 and п T7M alloy and pipe samples of THE "WISE" and "wise" alloy were also compared and heated together with the molded blank. Bt3-1 alloy billet molded elbow, three-way, four-way accessories. Titanium forgings manufacturers have studied the influence of the following factors on the physical and mechanical properties of parts: pre-low temperature oxidation treatment, glass enamel protective coating, heating medium and heating method, surface treatment after die forging.


Titanium alloy forgings manufacturer did not do pre - oxidation treatment of the billet, its surface is fish scale, pre - oxidation treatment of the billet surface smooth. In addition, the glass enamel coating on the surface of the pre-oxidized hot-molded blank is very easy to remove. The state of the surface layer (oxidized and aspirated) has a great influence on the mechanical properties, especially the plasticity of the hot-die forging billet. Sand blasting treatment can improve the plasticity. On the basis of preoxidizing the blank, glass enamel coating can also improve the surface plasticity of the blank.


When titanium forgings are heated titanium alloy billets in ordinary electric furnace, if the temperature exceeds the allotropic crystal transition temperature and the holding time is within 1h, it will not cause obvious suction on the surface, and the suction layer is easily removed by conventional sandblasting treatment. The method of heating billet before die forging in the pseudo-liquefied layer of loose material is worth special attention. This heating method is the most effective way to enhance the heat exchange process between particles, gases and billet surfaces. The heat transfer efficiency in the loose material pseudo-liquefaction layer is 1.5 orders of magnitude higher than that in the forced convection furnace, and roughly equivalent to that in the molten salt furnace.