Primary Types of Aluminium Heat Treatments

12 March 2021

Non-ferrous metals are metals that are not comprised of iron content, which gives them significant resistance to corrosion and rust that can be very useful for outdoor applications. They are also non-magnetic, allowing them to be used for electronic applications.

One metal that is part of the non-ferrous metal family is aluminium. It is lightweight, soft, and can be processed easily. This metal, however, has low strength. Therefore, different methods of heat treatment are carried out to alter their strength. Heat treatments also allow aluminium to be machined or welded easily, change their mechanical properties, obtain wear-resistant properties, improve brittleness, and enhance compatibility with other types of materials.

To date, there are numerous types of aluminium heat treatments that you can maximise. Some of these types are as follows:

Annealing

The plastic deformation of aluminium that is subjected to strain hardening allows its grain structures to slide against each other along slip planes. As the instances of plastic deformation continue, the number of slip planes decreases, requiring the aluminium to have more force to obtain further deformation. To reset the crystalline grain structure, restore the slip planes, and relieve the internal stress of an aluminium alloy, it must undergo the process of annealing. Annealing is conducted by heating the aluminium alloy between 298°C to 410°C for around thirty minutes to three hours. An aluminium alloy that is subjected to annealing can be worked more easily compared to one that has not been processed.

Solution Heat Treatment

Solution heat treatment, alternatively, is a process wherein the age-hardening elements are dissolved. During this process, a part must be rapidly cooled after heating to effectively distribute the dissolved elements in the alloy. The temperature needed by an aluminium alloy for the heating process ranges between 440°C and 526°C. The temperature must be, nevertheless, within ±12°C of the target temperature so that the solution heat treatment can yield great results. The soaking time of the heated part, subsequently, may range between 10 minutes and 12 hours, depending on its size and dimensions. Ultimately, it must be quenched to trap elements in place and avoid them from precipitating.

Precipitation Hardening

Precipitation hardening, also known as artificial aging, is another type of heat treatment that allows an aluminium alloy to reach its maximum hardness. This heat treatment process is conducted by heating an aluminium alloy between 115°C and 274°C, within ±15°C of the intended temperature. The alloy must be consequently soaked for around 6 to 24 hours and then cooled to room temperature. Once the precipitation hardening is finished, the aluminium alloy is expected to obtain a significant increase in yield strength, a slight increase in tensile strength, and a decrease in ductility. An aluminium alloy that cannot reach its peak hardness during natural aging at room temperature can utilise precipitation hardening.

To obtain high-quality aluminium heat treatment processes, feel free to contact us at Alpha Detroit Heat Treatment. We provide a wide range of services for all your heat treatment needs. Our expertise allows us to suggest the most appropriate process for your heat treatment requirements.

Optimized by: Netwizard SEO