Study On The Mechanism Of Ultrasonic Welding Of Zr Based Amorphous Alloys

In the recent years, BMG attracted much attention because of their excellent mechanical proties, magnetic proties, electrical properties,etc.. Zr 41.2Ti13.8Ni10-Cu12.5Be22.5(Vit1) is a typical example of Zr-base amorphous materials with advantages of good ductility, resistance to acid attac k, Argon ion beam irradiation resistance, so it looks like a kind of promising material. But because the limit of materials and equipment, the amorphous alloy size dimensions have been relatively small, it is hard for real industrial applications. This greatly limits the use of amorphous alloys. Bulk amorphous alloy obtained by connection of small scale bulk amorphous alloys may be one of the most effective methods. Using ultrasonic welding method can solve some problem s in traditional ways, in this article we use the ultrasonic welding to salve some problems above and do some research on the mechanism of it.This article works on the different experimental conditions, such as welding time, welding power and their influence on welding quality. Experiments sh ow that shear strength is proportional to the change of welding pressure within a certain range. When welding pressure is 0.2MPa the shear strength can reach up to 17.25 MPa, the longer welding time is, the better the surface morphology and shear strength change. When welding time is 3.5s the shear strength reaches maximum, 23 MPa nearby, Welding power can be represented by amplitude of welding indenter, welding amplitudes reach 40% when we get the optimal performance of the welded joints, and its shear strength is approximately 26 MPa. Surface roughness also has some influence on welding performance. When Ra is 10μm the shear strength can be achieved with a performance of 15 MPa. Preheating and aging treatment were also studied, both kinds of treatment can change the welding heat-affected zone, stress-relieving, improves mechanical properties of metallic glass. Data indicate that the shear strength could change and individually can be improved up to 17.85% and 15.38%.Mechanism of ultrasonic welding has not yet reached a consensus. In this article we want to analyse from the large number of tests and intended to confirm the mechanism of ultrasonic welding of Zr-based amorphous, namely that temperature of metal climbs to a constant range and get into supercold temperature zone and act as the so-called superplastic deformation. Amorphous alloys in the welding process have not melted, but the atoms reaches a certain distance so that they can get together rely on atomic forces. Good properties of amorphous alloys can remain in the whole process. We also made a good attempt on the connections of different kinds of amorphous materials.