After more than 200 hours of continuous work, a super large titanium alloy complex part close to the forming space limit of the equipment was trial manufactured and formed in the additive manufacturing center of Kunming University of technology on September 7. This is also the largest single titanium alloy complex part formed by laser selective melting so far.

　　Laser selective melting is a kind of metal 3D printing method. It uses laser as the heat source to scan the paved metal powder according to the discrete shape data of parts, so as to melt and stack the metal powder point by point, so as to realize the direct manufacturing of metal parts. The metal parts manufactured by this method have excellent mechanical properties, high surface quality and dimensional accuracy, which is a research hotspot in the field of metal 3D printing. The complex titanium alloy part made by Professor Li Zhenhua's research group has a size of 250 × two hundred and fifty × 257mm, the total amount of parts and supports exceeds 21kg.

　　It is reported that titanium alloy has excellent mechanical properties and corrosion resistance, and is widely used in aerospace, chemical industry, medical treatment and other fields. In the process of metal laser 3D printing, high residual stress will be generated, and the problems such as stress deformation and cracking during the forming of complex structural parts have always been the biggest challenge faced by metal 3D printing. These problems are more prominent in titanium alloy laser 3D printing. Professor Li Zhenhua and his cooperation team have carried out a lot of preliminary work in powder and composition control, component structure and position optimization, support design and stress release, remote monitoring, etc., and finally determined the test scheme, which has accumulated valuable experience for completing the printing of large and complex titanium alloy parts.

　　In recent years, the additive manufacturing center of Kunming University of technology has made great progress in 3D printing research in aerospace, medical treatment, mold and other fields. At present, more than 5700 undergraduates enter the manufacturing center to study and carry out innovation activities every year; There are more than 50 professional and technical personnel and doctoral and master's students engaged in research in the center.