Selectarc CUPROX 681

CUPROX 681 is a braze welding alloy formulated primarily from copper and zinc, supplemented with small amounts of silicon, nickel, manganese, and iron. Its purpose is to enhance adhesion and manage zinc vaporization. The alloy is available in bare rod form or coated with POLYFLUX. It offers good flow properties and is suitable for gap brazing applications. Due to its high zinc content, careful control of the heating cycle is crucial to prevent excessive zinc vaporization. This alloy is designed for joining a wide range of metals including steels, cast irons, and various alloys.

CUPROX 681 is particularly well-suited for applications in locksmith workshops and general fabrication. It is recommended for joining steel, cast iron, molded steel, and various alloys, including copper, bronze, brass, and nickel alloys. Specifically, it’s frequently used in the tubular construction industry for metal furniture, bicycle frames, radiators, towel warmers, and various heating and cooling systems, as well as mining tools. It’s crucial to minimize heating cycles to avoid zinc vaporization and to maintain a controlled quench (above 300°C) to ensure a robust brazed joint.