In October 2019, HEHT Titanium Alloy Technology Co., Ltd. innovatively used cold crucible vacuum induction melting gas atomization technology to produce TA15 titanium alloy powder.
The nominal composition of the TA15 titanium alloy is Ti-6.5Al-2Zr-1Mo-1V, which is a near-alpha titanium alloy with high aluminum equivalent. It not only has good thermal strength and weldability of α-type titanium alloy, but also has process plasticity close to that of α-type titanium alloy. It is mainly used to manufacture load-bearing parts that work for less than 500 ℃ for a long time, such as various cabins, rudder wings, and engine air intakes of space vehicles.
With the development of metal 3D printing technology in the aerospace field, the demand for new titanium alloy powders such as TA15 is gradually increasing. Due to the high activity of titanium alloys, the production technology of spherical titanium powder is relatively high. Traditional electrode induction smelting gas atomization and rotating electrode atomization and other powder production technologies have problems of low fine powder rate, high cost, and plasma tungsten electrode pollution. Limit the application and promotion of titanium powder.
Advantages of cold crucible vacuum induction melting gas atomization technology for preparing metal 3D printing powder materials
HEHT uses cold crucible vacuum induction melting gas atomization technology to successfully produce and prepare TA15 titanium alloy powder suitable for metal 3D printing process. This technology combines water-cooled copper crucible vacuum induction suspension melting technology with supersonic gas atomization technology. Its advantages are:
(1) The water-cooled copper crucible is used for alloy smelting. During the smelting process, the melt is in a suspended state, the temperature of the crucible wall is in a cold state, and no reaction will occur between the melt and the crucible wall. high;
(2) Electromagnetic stirring can be used to obtain uniform melt superheat and chemical composition during alloy smelting, and a higher superheat melt can be obtained by increasing the induction coil power. The melt atomization effect is sufficient and the fine powder rate is high .
(3) After the alloy liquid is smelted, a small continuous liquid flow is formed through the diversion tube, which is crushed and solidified by the high-speed air flow generated by the atomizing nozzle to form fine powder particles. .
Features of TA15 titanium alloy powder produced
TA15 titanium alloy powder produced by cold crucible vacuum induction melting gas atomization technology has excellent properties such as low oxygen content, high sphericity, high loose package and tap density. After testing, the median particle size d50 of TA15 powder in the 15-53μm particle size range is 35μm, the oxygen content is less than 1000ppm, the bulk density and tap density reach 2.3g / cm3 and 2.8g / cm3, respectively. The 3D printing process requires low comprehensive cost and can be widely used in the field of 3D printing and powder metallurgy.
The mechanical properties of TA15 titanium alloy parts formed by the three techniques of laser selective melting forming (SLM), electron beam selective melting forming (EBM) and laser melting deposition (LENS) were tested. The results showed that the sample room temperature strength and elongation index were TA15 titanium alloy forgings are consistent, the tensile strength at 500 ℃ is higher than 770MPa, which meets the performance requirements of aerospace parts.
TA15 powder 3D printed parts performance
Established in 2013, HEHT Co., Ltd. is a titanium industry base under China Aerospace Corporation that specializes in the research, development, design, manufacture and service of high-end titanium alloy products. The company uses advanced cold crucible vacuum induction melting gas atomization and pulverization technology to produce The aerospace standard high-performance titanium alloy powder product has now fully built a spherical titanium alloy powder production line with a capacity of 30 tons per year. With the completion of the HEHT titanium powder production line, it will significantly improve the domestic high-end titanium alloy powder R & D and manufacturing level. And promote the rapid development of titanium alloy 3D printing and powder metallurgy technology.