PURPOSE:To prevent the micro crack produced at weld zone, by adding metals having melting point of their carbides and eutectic temperature of the carbides and matrixes higher than melting temperature of the matrixes, to heat resisting alloys, such as inconel type etc. CONSTITUTION:M6C of Mo is found in basic material, because Mo etc. is considerably contained in heat resisting alloys of inconel type etc. Micro crack is produced by molten deposit under heat stress of tension acting on heat-affected zone when carbide, such as M6C or MC, is melted. Thereupon, extremely small quantities of alloy elements, such as Nb, Ta etc., are added in order to prevent the production of micro crack repressing the deposit of M6C and then, melting point of carbide of alloy elements and C and eutectic starting temperature of the carbide and matrix (gamma), are made higher than melting starting temperature of the matrx. Hereby, the micro crack produced at electron beam weld zone, is prevented without giving nearly no hindrance to the physical and mechanical properties of heat reisting alloys and also, without bringing about cost up.
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