GB865658A - Improvements in or relating to solid-phase bonding of metals - Google Patents

Abstract

865,658. Making composite metal strip; jointing by rolling. TEXAS INSTRUMENTS Inc. May 28, 1957, No. 16971/57. Classes 83 (2) and 83 (4). In a method of solid-phase bonding of composite strip-metal, partial-strength bonds are formed by a sequence of at least two squeezing operations followed by a final sintering to form the permanent bond. In one example, metal strips 1, 3, Fig. 1, to be bonded pass through heating and scratch brushing apparatus 11 to remove surface film and through a dust-removing sweep chamber 13 before a two-stage reduction in roll stands 9, 23 to produce partial bonding prior to sintering. Rolls 17, 19, 21 between the roll stands guide the strips in a curved path to tension the strip 1 of softer metal and thereby assist in preserving the weak bond formed by the first roll stand 9. In modifications the initial weak bond may be preserved by guiding the strips between rolls or platens 31, Fig. 3, loaded hydraulically or by springs &c. Alternatively the initial weak bond may be preserved by driving the second set of rolls at a faster speed to maintain the strips under tension or by heating the strip to produce a partial sintering at temperatures below that at which brittle intermetallic compounds or liquid phases are formed. Examples are described for forming composite strips of copper and silver; copper and steel; silver and nickel; and aluminium and copper. Specifications 745,426 and 745,511 are referred to.