Method for making rock bits

摘要

Segments of a rock bit are secured together by electron-beam welding. The segments are slightly spaced apart prior to welding by a thin shim of alloying metal such as titanium which improves ductility of the weld and is a strong carbide-former during welding. The shim is positioned between adjacent segments in the region of the crown or dome of the bit. The resulting welded interface is a fine-grain stress-relieved structure with good ductility and resistance to cracking.