The process of solidifying two metals to one another is typically referred to as welding, save for those professionals who understand the difference between brazing and welding. For the most part, welding is the process of joining to metals which are melted together, through a variety of mediums, and are then filled with another material to form a solid and durable connection between the two metals. Welding is commonly used in joining materials like steel and iron and is used in a variety of settings, including underwater.
While the two techniques may seem similar, brazing is actually not the same metal-joining technique as welding. The process of brazing is different in that there is no melting of the original metals to be attached together. Instead a filler metal is melted, then placed at the joining point of the two metals to be attached to one another, where it is then cooled and solidifies the two metal materials together. Unlike welding, brazing can only be done under certain conditions as the hot filler metal needs a sufficient atmosphere to solidify the two pieces together.
While brazing vs welding will not be a topic of consideration, it is important to understand that there is a difference between the two techniques.
Like welding there are several brazing methods and brazing tools that can be used, each appropriate for different forms of metals to be joined and different uses of those metals. Each form of brazing requires various brazing supplies, based on the metals to be brazed, the atmosphere, and the type of brazing.
Through the process of furnace brazing metals are joined rather quickly and still very efficiently, for that reason it is one of the most popular forms of brazing for manufacturing industries that are producing numerous products. The equipment used for this form of brazing is easy to operate and can produce the filler metal at a particularly fast rate. However, as popular as this form of brazing is it is expensive and it requires the right atmospheric conditions to thoroughly fuse the metals together.
Torch brazing is usually used on an individual basis in which there is only the need to produce one item of metal fused together by heat. This process is the most common across the world and is considered to be more affordable as it can be done manually, as well as with automatic machines if you so desire. Perhaps more so than any other form of brazing, those who torch braze manually must use extreme caution at all times. No form of brazing should be done however, without prior training.
There are several pieces of equipment that are importantly incorporated into the brazing of metals. The following are just a few of those items:
The brazing rod is the actual metal that is used as filler, the metal that melts when it is heated to connect the other two pieces of metal. Brazing rods can be made from a variety of metals and each is appropriate for the brazing of different materials. For example aluminum brazing rods are only appropriate for use in the fusion of certain metals.
Blazing rods vary in thickness based on the types of brazing metal that is used and based on the metals that are bonded together. Getting a brazing rod that is too thick or thin can have a dramatic effect on the drying and final process of brazing that you are doing.
The two metals that are joined must be purified prior to the cooling of the brazing metal, this cleaner is called flux. Some brazing rods come coated with flux, whereas other brazing rods have to have it added. Brazing flux should be cleaned off the finished product as it is known to cause corrosion.
While an atmosphere is typically assumed there are various atmospheres that need to be used to solidify your brazing. Depending on the brazing metal that is used the atmosphere must be considered and altered. Some of the other atmospheres include Nitrogen, Argon, Hydrogen, and even vacuum chambers. Without the proper atmosphere the final brazed metals may not be able to firmly solidify.
Whether you are brazing steel or brazing cast iron it is important to find out the most suitable brazing rods for your base metals. Certain metals do not create a strong bond with other metals, for that reason it is critical that you understand the temperatures and strengths of the brazing rods with your original metals.
Brazing- Real World Applications
While there are smaller automotive and welding shops that integrate the use of brazing within their day to day activities brazing most commonly has a real world application in industrial settings. The following are just a few of the areas in which brazing is common practice:
Electronics manufacturers- Companies that produces televisions, radios, and even cameras commonly use brazing to fuse together metals and glass pieces, as well as metal and ceramics. Brazing is ideal in components that are small and hard to get to as welding in those areas would be nearly impossible.
Automotive industry- With a variety of metals under the hood of the car brazing is perfect for items on an engine block and even the successful implementation of pistons. Automotive manufacturers also need brazing tools which will help them produce thousands of the same car parts over and over.
Aeronautic industry- Several of the metals which are used in the engines of airplanes are joined through brazing because of the density ratios that must be maintained during flight.
While brazing and welding each have their ideal applications, requirements and conditions, brazing has proven to be superior to welding in several different applications. Understanding and learning the brazing of metals is a skill and a trade which will always be of use in our society. So long as the proper safety precautions are taken and there is proper training you can apply brazing techniques to just about anything.