Hub shaft induction heating and heat treatment process pert 1: hub shaft heat treatment technical requirements
Hub shaft (see Figure 1) is an important part of the wheel rim reducer. Its quality has a great impact on the quality of the whole vehicle, and the automotive industry has increasingly higher requirements on its performance. The hub shaft mainly ACTS as a load-bearing part and provides accurate guidance for the hub drive. It bears both radial and axial loads, so it requires higher dimensional accuracy and shape and position tolerances, which puts forward higher requirements for machining and heat treatment processes.In this paper, the development of induction heat treatment process is discussed, and an optimal process scheme is sought to achieve the purpose of high efficiency and low cost green manufacturing.
FIG. 1 Hub shaft before induction heating heat treatment
Hub shaft induction heating and heat treatment process: hub shaft induction heat treatment technical requirements
The hub shaft is produced by die forging process, and the main production process is as follows: die forging → roughing → tempering → fine tuning → induction heat treatment → fine grinding → assembly. The material is 42CrMo, and the hardness after quenching and tempering is 250 ~ 280HBW. The detection results of the chemical composition of the material are shown in Table 1.
Drawing technical requirements: induction heat treatment effective hardening layer depth 4 ~ 7mm, R1, R2 allowed 3 ~ 7mm, 89mm external circular end Angle allowed 6 ~ 13mm; The hardening area is shown in Figure 2, the surface hardness is 50 ~ 64HRC;The metallographic structure is acicular martensite with grade 3 ~ 8.
FIG. 2 Hub shaft induction heating quenching area