Low-temperature rapid diffusion welding device and method based on pulse current auxiliary heating

Abstract

The invention discloses a low-temperature rapid diffusion welding device and method based on pulse current auxiliary heating. The device comprises a graphite body heating power supply, a graphite body, electrodes, an interface heating pulse power supply and a sample. According to the method, graphite body radiant heat is mainly used, welding interface contact resistance heat and discharge heat are used as accessory, an original liquid phase is formed by the resistance heat and discharge heat which are formed at an interface to be connected by the pulse current, and diffusion welding is realized by virtue of less externally-applied extrusion force. The device and the method can be used for reducing the residual stress, obviously shortening the welding time, requiring smaller applied pressure and preventing workpieces from being subjected to serious deformation in a pressurization direction, are conductive to crushing oxidation films on the surfaces of materials and simultaneously can be used for reducing the material surface processing precision requirement; and the device disclosed by the invention is simple in process, smart in design and convenient in use, and can be widely applied to the diffusion welding of various nonmetals and metals.

Description

technical field [0001] The invention relates to a material connecting device and a connecting method thereof, in particular to a low-temperature rapid diffusion welding device and a welding method assisted by pulse current heating. Background technique [0002] At present, the diffusion welding method is suitable for the welding of most materials, especially for materials that are difficult to weld by other welding methods, such as Ni-based superalloys, superalloys, intermetallic compounds, metal matrix composites, and ceramics. The diffusion welding method has the following significant advantages: it is suitable for the connection between insoluble materials, and the high temperature performance of the joint is excellent; but the traditional diffusion welding method also has the following disadvantages: high requirements for the processing quality of the joint surface, large welding deformation, and long welding heat cycle time (connected materials Both the material and the...

AI Technical Summary

Problems solved by technology

The diffusion welding method has the following significant advantages: it is suitable for the connection between insoluble materials, and the high temperature performance of the joint is excellent; but the traditional diffusion welding method also has the following disadvantages: high requirements for the processing quality of the joint surface, large welding deformation, and long welding heat cycle time (connected materials and the materials to be joined must go through exactly the same welding thermal cycle process, which inevitably leads to high welding residual stress), thus limiting the application range of diffusion welding

In China, Peng Yong and others also use pulsed high current diffusion welding of AL-Li alloy 1420 (see literature Peng Yong, Fu Zhengyi, Wang Weimin, Wang Hao. Pulse high current diffusion welding of AL-Li alloy 1420. Journal of Welding, 2008, 29( 1): 57-60.), but the following problems have appeared in the above studies: the use of pulsed high-current thermal processing diffusion welding can form a connection point at the interface in a short period of time, but due to the use of high-current welding, it is easy to form a connection point inside the material Causes a large residual stress, which affects the improvement of the performance of the joint, and at the same time, the longer holding time affects the welding speed

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