EXPLOSIVE WELDING AND ITS PROCESS

In explosive welding, strong metallurgical bonds can be produced between metal combinations which cannot be welded by other methods or processes. For example , tantalum can be explosively welded to steel although the welding point of tantalum is higher than the vaporization temperature of steel.

Explosive welding is carried out by bringing together properly paired metal surfaces with high relative velocity at a high pressure and a proper orientation to each other so that a large amount of plastic interaction occurs between the surfaces. The work piece, held fixed is called the target plate and the other called flyer plate. While a variety of procedures have been successfully employed , the major techniques of the explosive welding can be divided into the contact techniques and Impact techniques.

In critical space and nuclear application, explosive welding permits fabrication of structures that cannot be made by any other means ; and in some commercial applications, explosive joining is the least costly method.

The major advantage of this welding includes the simplicity of the process, and the extremely large surface that can be welded. Also incompatible materials can be bonded, and thin foils can be bonded to heavier plating.

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Mechinopedia For Mechanical Engineers

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