METHOD OF MAKING ARTICLES WITH INNER SPACES BY EXPLOSION WELDING Russian patent published in 1999 - IPC

FIELD: mechanical engineering. SUBSTANCE: protective coating, thickness of 0.1-1.0 mm is applied to face surface and surface of die channels. Protective coating is formed by application of chalk suspension in liquid glass at the following relation of components, mass %: chalk 1-10, liquid glass - the rest. Tubular space-forming members with filler are placed in die channels. Blank is installed parallel to die with clearance in between. Blasting charge is placed on blank, and explosion welding is done. Mixture of sodium chloride and sodium thiosulfate is used as filler. Content of components in mixture is, mass %: sodium chloride 30-70, sodium thiosulfate, the rest. Steel die with trapezoidal or V-shaped channels is used. EFFECT: prevention of welding of articles to die, enhanced quality of joints, reduced labour input in manufacturing of articles with inner spaces. 10 cl, 1 tbl, 2 dwg, 5 ex