Aluminum-silicon-copper-yttrium solder for silicon carbide particle reinforced aluminum matrix composite soldering and preparation method for aluminum-silicon-copper-yttrium solder

Abstract

The invention discloses aluminum-silicon-copper-yttrium solder for SiC particle reinforced aluminum matrix composite soldering and a preparation method for the aluminum-silicon-copper-yttrium solder, and belongs to the technical field of welding solder. The solder comprises, by mass, 20.0%-28.0% of Cu, 6.5%-10.0% of Si, 0.05%-0.5% of Y, and the balance Al. The preparation method includes the following steps that A, Al and Al-Si alloy are placed in a crucible of a vacuum induction melting furnace, and high-purity argon is introduced after vacuumizing; B, the temperature is increased to 700 DEG C-800 DEG C through heating, and Al-Si-Cu alloy is formed; C, at the temperature of about 700 DEG C, Al-Y alloy is added, and after heat preservation is conducted at the temperature of 600 DEG C and standing is conducted, casting is conducted through a forming mold; and D, solder alloy is taken out, and after surface oxide skin is removed, remelting is conducted twice according to the same method. The solder is low in preparation temperature, good in wettability, capable of being well combined with a matrix and easy to control.

Description

technical field [0001] The invention relates to a silicon carbide particle reinforced aluminum matrix composite material (SiC for short) p / Al) welding filler metal and a preparation method thereof, in particular to an aluminum-silicon-copper yttrium filler metal used for brazing SiC particle-reinforced aluminum matrix composite materials and a preparation method thereof, belonging to the technical field of welding filler metal. Background technique [0002] High volume fraction SiC p Al / Al composites have broad application prospects in electronic packaging due to their excellent properties such as high thermal conductivity, low thermal expansion coefficient, and low density. Especially in the field of aerospace, it has irreplaceable advantages. Under the background of national energy conservation and emission reduction and continuous upgrading of military equipment, this type of composite material shows its important position as an excellent electronic packaging material. ...

AI Technical Summary

Problems solved by technology

In order to increase the wettability of this series of alloys, active elements that can improve the fluidity of the solder are mostly added, forming a multi-element alloy with more complex components, resulting in cumbersome and difficult smelting processes for the solder alloy and poor microstructure uniformity

Another study used the method of adding trace rare earth (Ce, Er) to Al-Si-Cu non-eutectic alloy to improve the wettability of solder, but the test showed that trace rare earth could not reduce the melting point of the alloy, and in the existing In the current technology, the method of molten salt protection is generally used for the smelting of solder alloys. This method is poor in standardization and operability, and it is easy to introduce elements such as Na and K, which also have negative metamorphic effects. Existing research has not solved the problem of rare earth species. , the amount of rare earth added, and the optimal coordination between alloy components, and there is no report on the influence of different rare earths on the structure and properties of Al-Si-Cu alloys. predict

Chinese patent application number 201310405563.4 discloses an Al-5.5Si-28Cu eutectic solder alloy containing rare earth cerium and its preparation method. By adding rare earth Ce, it is optimized on the basis of the original Al-5.5Si-28Cu solder Its mechanical properties improve the wetting properties of the solder. Experiments have proved that the addition of this rare earth Ce has the greatest effect on the modification of the solder of the Al-5.5Si-28Cu alloy composition, and to a certain extent meets the requirements for the reinforcement of silicon carbide particles. Aluminum-based composite material brazing filler metal requirements, but in practice it is found that this solder has the following disadvantages, one is that it has a very large brittleness and hardness, which will split the continuity of the alloy matrix, and cannot Coordinated and synchronized deformation with the base metal, it is easy to generate cracks and expand inside the solder alloy, and the brittleness of the solder alloy increases the difficulty of stripping the solder, that is, the formability of the ribbon solder is poor and the brittleness is extremely high

When brazing composite materials in the later stage, the brittle ribbon-shaped solder is easily crushed during the assembly stage, and micro-cracks appear, resulting in loose brazing joint structure after welding, and there are defects such as holes and micro-cracks, which affect the airtightness of the packaging material sex

At the same time, due to the high brittleness of the brazed joint alloy, the stress at the joint is relatively large, which will also cause the shear strength of the brazed joint to be low. The second is that the melting temperature of the solder is relatively high; Higher temperature and process time, the fourth is that the rare earth Ce has a high and unstable burning loss rate during the preparation process, resulting in uncontrollable and unstable product quality in the alloy preparation process. It can be seen from the above that although a small amount of rare earth is on The modification of materials is generally understood by technical personnel, but it is applied to the specific welding filler metal of silicon carbide particle reinforced aluminum matrix composite material. Although the doping of Ce has achieved a good effect on the solder alloy composition of Al-5.5Si-28Cu It has a certain effect, but there are still many shortcomings. Not every kind of rare earth can achieve good results when doping the solder. In this solder, in order to achieve good results, the type of rare earth elements, doping Impurities, raw materials, and preparation methods are not predictable, so in order to improve the benign efficiency of rare earth modification of the solder, finding suitable alloy components, doping elements, raw materials, and preparation methods is a blank that needs to be filled in this field

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