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General shaft materials and heat treatment

1. Materials for general shaft precision parts
1) General shaft parts and materials are commonly used 45 steel, 40Cr, bearing steel GCr15, spring steel 65Mn, ductile iron can also be used for high precision shafts; 20CrMnTi, 20Mn2B, 20Cr, etc. for high speed and heavy load shafts Carburized steel or 38CrMoAl nitrided steel.
2) Common shaft parts are commonly used for round bar stocks and forgings; large shafts or complex shafts are made of castings. After the blank is heated and forged, the inner fiber structure of the metal can be evenly distributed along the surface to obtain high tensile strength, bending strength and torsional strength.

2. Heat treatment of general shaft parts
1) Forging blanks must be arranged for normalizing or annealing before processing to refine the grain inside the steel, eliminate forging stress, reduce material hardness and improve cutting performance.
2) The quenching and tempering is generally arranged after the roughing and before the semi-finishing to obtain good comprehensive mechanical properties.
3) Surface quenching is generally arranged before finishing, which corrects local deformation caused by quenching.
4) For shafts with high precision requirements, after local quenching or rough grinding, low temperature aging treatment is also required.