Brazeën

Brazeën is a metalworking technique used to join two or more metal pieces by introducing a molten filler metal that has a lower melting point than the base metals. The base parts are not melted, which distinguishes brazing from welding and places it between welding and soldering in terms of temperature and strength. In Dutch-language technical literature, brazeën describes the operation and the resulting joints.

The process typically involves cleaning and fitting the parts, applying flux to prevent oxidation and improve wetting, and heating the assembly until the filler metal flows into the joint by capillary action. When the filler cools, it solidifies to form a strong, hermetic joint. Common filler metals include brass and bronze alloys, silver-based alloys, copper-phosphorus, and aluminum-silicon alloys, chosen based on the base metals, desired strength, and service conditions. Heating methods range from hand-held torches to ovens, furnaces, or induction systems, with careful control to avoid overheating or distortion.

Applications of brazeën span several industries. In jewelry and art metalwork, brazed joints enable delicate assemblies. Plumbing and HVAC use brazing for copper and other metal tubes due to good corrosion resistance and watertight seals. The technique is also employed in automotive and aerospace sectors for brazed heat exchangers, electrical components, and assemblies requiring dissimilar metals.

Advantages include strong joints at moderate temperatures, the ability to join dissimilar metals, and relatively simple tooling. Limitations involve the need for clean surfaces, flux handling, and potential thermal distortion. Proper inspection and post-braze cleaning are important for long-term reliability.