METHOD FOR JOINING MATERIAL HAVING SMALL COEFFICIENT OF LINEAR EXPANSION AND COPPER

摘要

PURPOSE:To provide a method for joining a material having a small coefft. of linear expansion and copper which can prevent deformation, yields excellent joint strength and is low in treatment cost. CONSTITUTION:A brazing filler metal is inserted between a carbon plate and an oxygen-free copper plate and these materials are heated up to a joining temp. TB. The carbon plate and the oxygen-free copper plate are pressurized to each other under 0.002 to 1.0kgf/cm<2> pressurizing force. The pressurizing force PC is increased to >=5kgf/cm<2> from the temp. TC within the temp. range of (solidus line temp. of the brazing filler metal - 50 deg.C) to (liquidus line temp. of the brazing filler metal + 50 deg.C) at the time of cooling. The average cooling rate at the time of temp. falling from 600 deg.C to 300 deg.C is specified to 10 to 100 deg.C/ hour.