Changes in mechanical properties of austenitic stainless steel after intergranular corrosion

After intergranular corrosion occurs in austenitic stainless steel, its mechanical properties change. In 321 stainless steel, cracks appear when intergranular corrosion occurs. Cracks can cause the microstructure of the material to become uneven, thereby affecting its hardness. Typically, intergranular corrosion causes changes in the microstructure near the grain boundaries. These changes may cause hardening or softening in the grain boundary region. In 321 stainless steel, after intergranular corrosion occurs, cracks form, and the area surrounding the cracks may undergo constitutive hardening. Constitutive hardening refers to the increase in hardness of a material after being subjected to stress, due to lattice misalignment and dislocation movement. Therefore, due to crack formation caused by intergranular corrosion, the microstructural hardness of 321 stainless steel material may change. The specific changes depend on factors such as the degree of corrosion, the shape of cracks, and the treatment condition of the material. However, in general, the presence of cracks leads to a decrease in the mechanical properties of the material, including an increase in hardness. .