The cold - working process, such as cold bending or cold rolling, can significantly influence the mechanical properties of A36 angle steel. When A36 angle steel undergoes cold working, the steel's crystal structure deforms, leading to strain hardening. This results in an increase in the yield strength and tensile strength of the steel. For example, after cold bending, the yield strength of A36 angle steel may increase by 10 - 15% in the deformed areas. However, this also reduces the ductility of the steel. The elongation percentage may decrease, making the steel more brittle and prone to cracking under further stress.
To mitigate these negative effects, several precautions should be taken. First, it is essential to control the degree of cold deformation. Excessive cold working can cause excessive strain hardening and a significant loss of ductility. Second, annealing treatment can be carried out after cold working. Annealing involves heating the steel to a specific temperature and then slowly cooling it, which can relieve internal stresses, restore some of the ductility, and improve the overall performance of the steel. Additionally, during the cold - working process, proper lubrication should be used to reduce friction and prevent surface damage, which could lead to stress concentrations and potential cracking.