A: Physical and chemical properties.
1) Density. After cold deformation, the density of aluminum is reduced due to defects such as microcracks or macroscopic cracks and cracks in the crystal and between the crystals.
2) Resistance. The destruction of intergranular materials causes direct contact of crystal grains, ordering of crystal grains, intergranular and intragranular cracking of aluminum profiles, etc., all of which have a significant influence on the change of electrical resistance. The first two reduce the resistance as the degree of deformation increases, while the latter is the opposite.
3) Chemical stability. After cold deformation, the material can be increased in height, making its chemical properties more unstable and susceptible to corrosion, especially stress corrosion.
B: Mechanical properties.