In situ self-generated nano al 2 o 3 Laser additive manufacturing method for reinforced aluminum matrix composites

Abstract

The invention discloses an in-situ self-generated nano-Al 2 o 3 A laser additive manufacturing method for strengthening an aluminum-based composite material, the method comprising the following steps: (1) mixing ZnO ceramic powder and AlSi10Mg aluminum alloy powder and ball milling to obtain a ZnO / AlSi10Mg composite powder; (2) preparing the composite powder The laser selective melting process is used for additive manufacturing forming to form a solid sheet; (3) The laser re-scans the solid sheet to form a remelted sheet; (4) Repeat steps (2) and (3) to finally form the original self-generated nano-Al 2 o 3 Reinforced aluminum matrix composites. In the present invention, laser is used to excite Al and ZnO to generate aluminum thermal reaction between them in situ. 2 o 3 Ceramic particles, and by improving the overall flow process design of the method, combining laser selective melting and laser remelting scanning, the aluminum matrix composite material obtained has high density, fine microstructure, and in-situ self-generated Al 2 o 3 The particle size is nanoscale, uniformly distributed, and its phase interface is well combined with the aluminum matrix.

Description

technical field [0001] The invention belongs to the technical field of preparation of aluminum-based composite materials, and more specifically relates to an in-situ self-generated nano-Al 2 o 3 Laser additive manufacturing method for reinforced aluminum matrix composites. Background technique [0002] Aluminum matrix composite material is an advanced material compounded by a specific process with particles, fibers or whiskers as the reinforcing phase and aluminum or aluminum alloy as the matrix. Aluminum-based composites not only have the characteristics of good wear resistance, easy processing, and low density of the aluminum matrix, but also have the advantages of high hardness, low expansion coefficient, and high-temperature stability of the reinforcing phase. Due to its excellent comprehensive properties, aluminum matrix composites have become one of the best candidate materials in aerospace, rail transit and other fields. There are many traditional methods for prepa...

AI Technical Summary

Problems solved by technology

At present, the aluminum matrix composites formed by laser selective melting mostly use the direct external method to add the reinforcement phase, and seldom use the in-situ self-generation method. The reason is that the direct external method can flexibly introduce reinforcement phases of different sizes, shapes and contents into the aluminum In the matrix, the in-situ self-generation method still has problems such as difficult to control the reaction process, easy to form coarse and harmful phases, the heat released by the reaction makes the melt unstable, difficult to spread evenly, and the formed material has low density.

However, when the reinforcing phase is introduced directly, it will easily lead to uneven distribution of the reinforcing phase, agglomeration, and poor interface bonding with the matrix.

Images