Numerical simulation and experimental study of melting process of titanium wire based on high frequency induction melting gas atomization

Additive manufacturing is an advanced manufacturing technology that uses continuous physical layers of additive to create three-dimensional objects. The additive manufacturing technology characterized by digitalization, networking, personalization and customization will promote the third industrial revolution. Additive manufacturing technology of titanium alloy is widely used in aerospace, biomedical and high-end industrial manufacturing fields. Titanium alloy powder is the basis of additive manufacturing of titanium alloy and also the most important component of industrial chain P. Based on the characteristics of the chemical nature very lively, titanium alloy at high temperature with the most elemental and compound, so the titanium alloy during smelting are highly susceptible to pollution. High purity titanium alloy powder preparation, the main reason lies in the melting technology of titanium alloy, thus severely restricts the application in the field of titanium alloy in material manufacturing. Suitable for raising material made of high quality titanium alloy powder should have low oxygen content, no impurity pollution characteristics, therefore, based on the requirement of titanium alloy smelting of aerosol for non-contact smelting technology.

At present, the main preparation methods of spherical titanium and titanium alloy powder for additive manufacturing are inert gas atomization, plasma atomization and electrode induction melting gas atomization.

Conclusion:
1) The optimal parameter of titanium wire induction melting model is obtained through simulation study: the output frequency of power supply is 450 kHz.

2) The critical wire feeding speed of the liquid flow with a length of 15 mm was obtained from the simulation study, which was 45 mm/s. Under this condition, the critical output power of the power supply is 34 kW when the melt superheat is 350 ℃.

3) Experimental study shows that the critical wire feeding speed of the liquid flow with a length of 15 mm for TC4 titanium wire is 50 mm/s, and the error between the experimental value and the simulated value is 10.0%.Under this condition, the critical output power of the power supply is 38 kW, and the error between the experimental value and the simulated value is 10.5%.The experimental results and simulation results are mutually verified, and the engineering application basis of titanium wire melting is obtained.