Brazing refers to the process of joining similar or even dissimilar metals together using a filler metal. Filler metals typically contain a base of copper and either silver, nickel, zinc, or phosphorous. This process is similar to welding, but the key difference is that brazing does not melt the base metal because it uses lower temperatures (between 900 and 2200 degrees Fahrenheit). This makes brazing the preferred method for joining dissimilar metals. When brazing stainless steel or other materials, the results are strong and in many cases will be stronger than the base metals that were joined together. Companies that provide heat treating services will help with annealing and brazing steel. After such a company is hired, here are the steps this company will take when brazing steel:
- Prepare the Work Surface: Remove flammable items from the work surface and surrounding area. Clean the metal pieces to remove chemical residues, dry it thoroughly, and then clean the stainless steel pieces.
- Apply Flux: Flux is a chemical cleaning agent with more than one function at a time, and is used in metal joining and extractive metallurgy. The flux has two roles when brazing stainless steel; it dissolves oxides on the metal surface and acts as an oxygen barrier to reduce oxidization.
- Make sure the work surface has a brass plate to absorb excess heat: A company that provides heat-treating services will already be equipped with a necessary brass plate.
- Begin Heating the Metals: Pieces should be placed on the brass plate and then heated using a torch. The two pieces will continue to be heated until the stainless steel surface is melted off.
- Press the Pieces Together: This will prepare the pieces for the process of adding the filler.
- Prepare the work area for filler material use: Clean the work area and then use a flux to clean the stainless steel.
- Heat the filler metal on the brass plate: Once again, heat the steel so that it is hot enough to join with the filler metal. The best way to determine if it is hot enough is to touch the filler metal to the stainless steel. The steel is hot enough if the filler metal melts on contact.
- Join the metals together: When the stainless steel is warm enough, join it to the filler metal to form a bond.
Companies that provide heat treating services might have specialized tools or resources that make this process easier to complete. When brazing steel, extra care must be taken to prevent oxidization. Additionally, the heat cycle must be well controlled, the cooling cycle must be controlled and robust, and atmospheres must be robust. Stainless steel will end up with maximum corrosion resistance when brazing or annealing is performed by a competent organization that provides heat treating services. Organizations that need help brazing steel should locate a company with years of experience that can guarantee consistent brightness and on-time delivery.