Welding Metallurgy of

Analytical approach for describing the collapse of surface asperities under compressive stress during rapid solid state bonding

Effect of micromorphology at the fatigue crack tip on the crack growth in electron beam welded Ti-6Al-4V joint

Characterization and mechanical properties of thick TC4 titanium alloy sheets welded joint by vacuum EBW

Modeling fluid dynamics of vapor plume in transient keyhole during vacuum electron beam welding

A comparative study on electron beam welding and rigid restraint thermal self-compressing bonding for Ti6Al4V alloy

Study on rigid restraint thermal self-compressing bonding – A new solid state bonding method

The invention provides a rigidity restraint hot self-extruding connection method. The method includes the steps of conducting rigidity restraint on butt joint materials to be connected, heating the interface areas of the materials to be connected through non-melt scanning so that the temperature difference can be produced between hot metal in the heating area and the surrounding cold metal, generating a thermal elastoplastic stress-stain field under the common action of the temperature difference and the rigidity restraint, and conducting self-extruding on the metal, in the thermoplasticity state, in the interface areas so that diffusion and connection can be achieved. According to the rigidity restraint hot self-pressing connection method, rigidity constraint hot self-extruding connection is achieved through the external rigidity constraint and butt joint face non-melt local heating, relying on external pressure is avoided in the solid phase connection process such as the diffusion welding process, in-furnace overall heating is avoided due to local heating, the technological process is simple, and limits to the sizes of workpieces in existing diffusion connection are also eliminated.

Rigidity restraint hot self-extruding connection method

Method of connecting sheets by thermal self-pressing

Thermal self-compressing bonding (TSCB) is a new solid-state bonding method pioneered by the authors. With electron beam as the non-melted heat source, previous experimental study performed on titanium alloys has proved the feasibility of TSCB. However, the thermal stress–strain process during bonding, which is of very important significance in revealing the mechanism of TSCB, was not analysed. In this paper, finite element analysis method is adopted to numerically study the thermal elasto-plastic stress–strain cycle of thermal self-compressing bonding. It is found that due to the localized heating, a non-uniform temperature distribution is formed during bonding, with the highest temperature existed on the bond interface. The expansion of high temperature materials adjacent to the bond interface are restrained by surrounding cool materials and rigid restraints, and thus an internal elasto-plastic stress–strain field is developed by itself which makes the bond interface subjected to thermal compressive action. This thermal self-compressing action combined with the high temperature on the bond interface promotes the atom diffusion across the bond interface to produce solid-state joints. Due to the relatively large plastic deformation, rigid restraint TSCB obtains sound joints in relatively short time compared to diffusion bonding.

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Bing Wu

Papers

A comparative study on electron beam welding and rigid restraint thermal self-compressing bonding for Ti6Al4V alloy

Study on rigid restraint thermal self-compressing bonding – A new solid state bonding method

Rigidity restraint hot self-extruding connection method

Method of connecting sheets by thermal self-pressing

Numerical Study on the Stress–Strain Cycle of Thermal Self-Compressing Bonding