I would like to address and discuss a specific question presented by a customer on our Alumaloy forum recently. “What is the difference between brazing and using Alumaloy on my aluminum repair project?” Please allow me a few moments to lay out the similarities and differences of repairing your aluminum project with Alumaloy versus repairing by brazing with bronze or copper.
First I will cover the similarities. Most metal workers will recognize that working with Alumaloy is very similar to brazing with bronze or even copper in the respect that you are bonding a broken piece of metal by melting another piece of metal to form a bond at the break. The process of brazing is a bonding of two or more metal parts with a different type of metal. Most often bronze is the metal of choice, although copper may also be used. When using Alumaloy you are also bonding two pieces of metal together. However, now you are using an aluminum alloy. In both cases, the metal is heated and melted to repair the break. The tools that are used are the same and the temperature that you need to work at is also the same. Another similarity is the use of a product called “flux”. (Flux protects the metal from oxidation during the bonding process, reducing the chance of oxidation.) Flux is used with some of our other products such as Castaloy and Steelaloy but not Alumaloy.
In both brazing and in working with Alumaloy, the step by step process of repairing aluminum is identical. The parts to be joined are lined up and the tacking is done. To “Tack”, means that the metal to be joined with the bronze or Alumaloy is heated and the rod is applied to the meeting place. The rod will have a lower melting point than the parts to be joined so it will leave a droplet joining the two. Other “tacks” are done, using the same process, to keep the metal parts from pulling apart due to expansion from the heat. Once the tacking is done the main repair can begin. Again the metal parts are heated up to the temperature for melting and the rod is touched to them leaving behind liquid metal to fill in the gap and hold the two parts together. If done properly, all the gaps will be filled with rivulets of now hardened metal, holding the two independent parts as one whole, making the repair complete.
Now I will discuss the differences. Really, there is only one difference, Alumaloy is stronger. It is stronger than aluminum, copper and bronze. This is due to the fact that it is an alloy. In our special formula, we have been able to combine aluminum with other metals to create a product that has more tensile strength than in its original form. By using an alloy that has the same properties as the metal that was broken, a more complete bond is created. Simply put, your aluminum is now better than when you started. Since the area that was broken before may have been due to a shortcoming in the original metal, you can now rest assured that you have added a new level of durability to your project.
We hope this has helped to clear up any questions you may have had regarding the differences of our product and the brazing process. As always, if you have any questions or suggestions please address them at our aluminum repair forum and we will do our best to answer them and make new information available to our customers as requested or needed.