Most people in metal fabrication and metal production know that aluminum is an excellent metal for resisting rust and corrosion. Ergo, you might be wondering why there are heat treatments for aluminum. What can possibly be gained from heat treating? Here are some reasons given by an aluminum heat treating company.
Annealing to Reduce Stresses
Formed and cast aluminum objects can be faced with stresses that can cause aluminum to stress-fracture. When and where you definitely do not a stress fracture to occur, the aluminum has to be stronger. Heat treating it via annealing reduces the stresses in these cast aluminum items.
Precipitation Hardening to Improve the Chemical Bonds of Liquid Aluminum
Prior to casting aluminum objects, one particular heat treatment can increase the aluminum’s chemical bonds at the atomic level. In short, you are changing the atomic structure of the aluminum in order to best manipulate it into something that is both malleable and very strong. There are a couple of slightly different approaches to precipitation hardening.
Homogenization in dairy is the breaking up of milk fats to evenly distribute the fats throughout the milk. A very similar process is used in heat treating aluminum. The aluminum ingots have some impurities in them, so to make the aluminum more uniform in its chemical structure the metal is melted and stirred to become homogenized. As a result, there is no one large area of impure metal in a poured or cast aluminum object that ends up being weaker than the rest because the impurities have been broken down and dispersed throughout by the aluminum heat treating company.