How to distinguish the state of aluminum profiles: T4, T5, and T6？

Aluminum is a very commonly used designated material for extrusion and shaping profiles because it has mechanical properties that make it highly suitable for forming and shaping metals from billet sections. The high ductility of aluminum means that the metal can be easily formed into various cross-sections without consuming a lot of energy during processing or shaping, and the melting point of aluminum is usually about half that of ordinary steel. These two facts mean that the energy consumption of the extrusion Aluminum Profile process is relatively low, thereby reducing the cost of molds and manufacturing. Finally, aluminum also has a very high strength-to-weight ratio, making it an excellent choice for industrial applications.

You often come across the designation such as 6063-T5/T6 or 6061-T4 in the material column. Here, the numbers 6063 or 6061 represent the grades of aluminum profiles, while T4/T5/T6 indicate the states of the profiles. So, what are the differences between them?

For example: In simple terms, the 6061 grade aluminum profiles have better strength and machining performance. They possess high toughness, good weldability and corrosion resistance. The 6063 grade aluminum profiles have better plasticity, enabling the material to achieve higher precision. At the same time, they have higher tensile strength and yield strength, exhibit better fracture toughness, and possess high strength, wear resistance, corrosion resistance and high-temperature resistance. 

1.The T4 state is: solution treatment + natural aging. That is, after the aluminum profiles are extruded from the extruder and cooled, they are not aged in the aging furnace. The aluminum profiles without aging have relatively low hardness and good ductility, which is suitable for deformation processing such as bending in the later stage.

2.The T5 state is: solution treatment + incomplete artificial aging. That is, after extrusion, they are air-cooled and quenched, and then transferred to the aging furnace for holding at around 200 degrees Celsius for 2-3 hours. The state of the aluminum profiles after being taken out of the furnace. The aluminum profiles in this state have relatively high hardness and certain ductility. It is the most commonly used in curtain walls.

3. The T6 state is: solution treatment + complete artificial aging. That is, after extrusion, they are water-cooled and quenched. The artificial aging after quenching is at a higher temperature and for a longer time than T5, so as to achieve a higher hardness state. It is suitable for occasions where the hardness of the material is required to be relatively high.

In summary, the success of custom aluminium profiles depends on a number of key elements such as design accuracy, material selection, production processes and quality control. It is only when these elements work together that high quality aluminium profiles can be manufactured to meet specific needs and help a variety of projects go smoothly.