How to improve the strength of the aluminum profile?

The strengthening of aluminum alloy is mainly to increase its resistance to dislocation action, so there are two ways to strengthen aluminum alloy: liquid treatment and solid state treatment.

Aluminium extrusion

Liquid treatment is the strengthening of dispersion distribution of carbide, boride and nitride in aluminum matrix melt through alloying and chemical reaction. The interface between the reinforced phase and the matrix, which is generated by the reaction, is clean, well combined, fine particles and uniform distribution, so the dispersion strengthening effect of the alloy is better. Liquid treatment mainly consists of alloy strengthening and heterogeneous strengthening.

The strengthening methods of aluminum alloy are solid dispersion strengthening, solid solution strengthening, precipitation strengthening, fine-grained strengthening, deformation strengthening and so on.

Dispersion strengthened non coherent rigid particle dispersions for aluminum alloys are called dispersion strengthening. In order to achieve good reinforcement effect, dispersions are required to have low solubility and diffusion rate in the aluminum matrix, and small particles with high hardness.            

Solid solution strengthening is based on solute atoms dissolved into the matrix metal and the dislocation is generated by nail insertion to increase the frictional resistance of dislocation movement to improve its deformation resistance. The addition of alloying elements to pure aluminum leads to the formation of Al based solid solutions, resulting in lattice distortion and resistance to dislocation movement, thereby increasing the strength of aluminum.            

Precipitation strengthening results from the precipitation of stable second phase through supersaturated solid solution, and the formation of solute atoms in the metastable region. The supersaturated solid solution heated to a certain temperature is precipitated, and the generation of the metastable phase of the common lattice produces aging strengthening, and the intensification of the secondary phase precipitation is also called precipitation strengthening. During the aging process, the effect of precipitation strengthening on the strength and hardness of aluminum alloy is greatly related to the structure and properties of the strengthening phase.            

Fine grain strengthening mainly uses grain boundary to impede the dislocation, by refining grain to increase grain boundary or improve grain boundary properties, impede dislocation movement and improve material strength. For aluminum alloys that can not be precipitated or precipitated, the strength and plasticity of the alloy is improved by adding microalloying elements to the modification and refining the microstructure. For example, adding sodium, sodium or antimony as a modifier in Al Si alloy can improve the plasticity and strength of the alloy.            

Deformation hardening is a high-intensity strengthening method by which plastic deformation causes the alloy to produce substructure and work hardening. The increase of dislocation density is the essence of deformation strengthening, the greater the dislocation density is, the increase of dislocation density is the essence of deformation strengthening, the greater the dislocation density is, the more opportunities for dislocation in the process of deforming and the greater resistance to each other during the process of dislocation, the greater the resistance between each other, and the stronger the deformation resistance and the strength of the alloy. The higher the degree is, and the plasticity is greatly reduced.

 


Post time: May-10-2018