The selection of materials for shaft parts is mainly based on the strength, stiffness, wear resistance and manufacturing process of the shaft, and strives to be economical and reasonable. The commonly used materials for shaft parts are 35, 45 and 50 high-quality carbon steels, of which 45 steel is the most widely used. Ordinary carbon steels such as Q235 and q255 can also be used for shafts with small or less important loads. Alloy steel can be used for those with large stress, limited axial size and weight or some special requirements.