3D printing aluminum-lithium alloy and application thereof

Abstract

The invention relates to the field of 3D printing metal materials, in particular to a 3D printing aluminum-lithium alloy and application thereof.The 3D printing aluminum-lithium alloy comprises, by mass, 2.1%-3.5% of Li, 3.5%-6.8% of Zn, 1.8%-2.5% of Cu, 1.8%-3.0% of Mg, 0.05%-0.15% of Zr and Filt; , 0.05%, Silt; 0.05%, Nat; 0.001%, Cat, 0.001%, Cat; 0.001%, Hlt; the 3D printing aluminum-lithium alloy disclosed by the invention has the characteristics of high alloying, alloy economy, light weight and 3D printing adaptability, can be used for printing light metal structural parts in the field of aerospace, and particularly realizes the application of manufacturing aircraft components by utilizing a powder bed electron beam 3D printing technology.

Description

technical field [0001] The invention relates to the field of 3D printing metal materials, in particular to a 3D printing aluminum-lithium alloy and its application. Background technique [0002] The lightweight characteristics of aerospace vehicle products are crucial to its development and application. For example, if the power system remains unchanged, the rocket’s own weight can be reduced by 1 kg, which can save nearly 100,000 yuan in launch costs; Can increase the range of 15 kilometers. With the development of major projects in the aerospace field at home and abroad, such as large aircraft, manned spaceflight, moon fire detection, space station, cargo spacecraft, and new-generation weapons and equipment, lightweight materials and their preparation technology updates are imminent. Aluminum-lithium alloy is recognized as the most ideal lightweight structural material in the world, with great potential economic benefits. Many countries attach great importance to the deve...

AI Technical Summary

Problems solved by technology

However, there are currently several outstanding problems: (1) All aluminum-lithium alloys currently in use are deformed alloys, which need to be combined with plastic forming processes such as forging, rolling, and extrusion, and there is no real cast aluminum-lithium alloy. , cannot be used to prepare components with complex structures in aerospace vehicles, such as products with ribs, irregular channels, variable cross-sections, concave-convex tables, etc.

(2) In order to pursue comprehensive performance, the new generation (third generation) aluminum-lithium alloy reduces the content of lithium, and the alloy density is greater than 2.7g / cm 3 , Compared with other aluminum alloys, the advantages are not obvious enough

(3) The current aluminum-lithium alloy production line has a long process, a long product preparation cycle, many technical difficulties, difficult product quality control, and it is difficult to adapt to the characteristics of aerospace small batches and multiple varieties

(4) Our country has not fully mastered the core technology in the conventional aluminum-lithium alloy smelting process, and the production lines that can realize the industrialization of aluminum-lithium alloys are all from abroad. At present, there is no completely independent and controllable aluminum-lithium alloy production line

The density of aluminum alloy is low, it is easy to powder in laser 3D printing, it is not easy to control, the density of aluminum-lithium alloy is lower, it is more difficult to control, and the strength of aluminum-lithium alloy in this patent is higher, cooling too fast during the printing process, solidification High stress, easy to crack

Therefore, the laser 3D printing of the aluminum-lithium alloy described in the patent has shortcomings in its own characteristics and technical difficulties, and its materials and preparation methods are not suitable for 3D printing of high-demand aircraft components.

[0005] Metal 3D printing methods are divided into laser, arc and electron beam according to the heat source; Among them, the powder bed electron beam 3D printing technology (SEBM) has the advantages of high energy utilization rate, high power, fast processing speed, low operating cost, and high vacuum protection. The preheating process provided by the high scanning speed can effectively reduce the thermal stress during the forming process. However, due to the rapid movement of the heat source, the rapid heating, melting, solidification and cooling speed of this technology, the serious heating imbalance and high temperature gradient, the tissue and thermal stress Large, and with the accumulation of thermal stress, it is easy to produce large deformation or even cracking, and at the same time, it is subject to changes in the solidification process of the alloy, so this greatly limits the printing materials that can be used for SEBM

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