The impact of high-temperature environments on the performance of aluminum profiles

Aluminum profiles exhibit high plasticity and low resistance at high temperatures. Coupled with accelerated atomic diffusion and complete recrystallization, this is conducive to the improvement of the microstructure. Under a stress state dominated by triaxial compression, hot deformation can most effectively alter the as-cast structure of aluminum profiles. By applying an appropriate amount of deformation, the as-cast structure can undergo the following beneficial changes.

(1) In general, hot deformation is accomplished through multiple repeated passes. During each pass, the processes of hardening and softening occur simultaneously. Industrial aluminum profile deformation breaks the coarse columnar grains. At the same time, it can help heal some minor cracks.

(2) The hydrostatic pressure in the stress state can promote the welding of bubbles present in the as-cast structure, compact shrinkage cavities, densify looseness, and transform it into a denser microstructure.

(3) Due to the enhanced atomic thermal motion at high temperatures, under the influence of stress, aided by the free diffusion and heterogeneous diffusion of atoms, the relative inhomogeneity of the chemical composition in the cast ingot can be reduced.

Through hot deformation, the cast ingot structure is transformed into a deformed (or processed) structure, resulting in higher density, uniformly fine equiaxed grains, and more uniform chemical composition, thereby significantly improving both plasticity and strength.