Honor No.1
Method for directly obtaining martensite die steel through laser 3D printing technology
The invention provides a method for directly obtaining martensite die steel through a laser 3D printing technology. According to the method, a defined amount of Mn, Ni, Cr and other alloy elements are added to iron powder, and within a wide temperature range, martensite transformation is facilitated. The influence rules of laser linear energy density eta (the ratio between laser power and scanning speed) on the density, microscopic structure and mechanical property of an SLM forming part are analyzed, parameters of the laser 3D printing technology are optimized, and a mold of a complex structure in any shape is obtained. Moreover, the forming mold has high hardness, abrasion resistance and good impact toughness, and is better in performance than a mold manufactured in a traditional method. Accordingly, the method is particularly suitable for rapid forming of molds of a complex structure.Honor No.2
Method for manufacturing high-performance in-situ TiC reinforced titanium-based composite workpiece on basis of CNTs and laser additive manufacturing and processing technology
The invention discloses a method for manufacturing a high-performance in-situ TiC reinforced titanium-based composite workpiece on the basis of CNTs and a laser additive manufacturing and processing technology. The method includes the following steps that (1) the carbon nano tubes are subjected to preliminary ultrasonic dispersion treatment; (2) pure titanium powder with the average particle size of 45-75 microns is mixed with the carbon nano tubes to obtain a mixture, and CNTs/Ti mixed powder is obtained by ball-milling the mixture through a ball mill under the protection of argon; and (3) the ball-milled CNTs/Ti mixed powder is shaped through a laser additive manufacturing and processing method so as to obtain a high-performance in-situ TiC reinforced titanium-based composite body. The method has the advantages that in-situ TiC reinforcement phases are formed on the basis of a CNTs in-situ reaction and evenly distributed in a titanium substrate, and the interface bonding strength is high; grains of a composite are refined remarkably; net forming or near-net forming of a test piece can be achieved; any complex heterogeneous part can be formed.
