Abstract

To obtain a good surface layer performance of the complex functional profile during the high-speed cold roll-beating forming process, this paper analyzed the metal plastic flow and residual stress-formed mechanism by using a theoretical model of the metal flow and residual stress generation. By using simulation software, the cold roll-beating forming process of a spline shaft was simulated and analyzed. The metal flow and residual stress formation law in the motion were researched. In a practical experiment, the changes in the grains in the spline tooth profile section and the residual stress distribution on the tooth profile were studied. A microcorrespondence relationship was established between the metal plastic flow and the residual stress generation. The conclusions indicate that the rate at which the metal flow decreases changes gradually at different metal layers. The residual stress value is directly related to the plastic flow difference. As the roll-beating speed increases, the uneven degree of plastic deformation at the workpiece surface increases, and the residual stress in the tooth profile is generally greater. At the same roll-beating speed, the rate change trend of the metal flow decreases gradually from the surface to the inner layer and from the dedendum to the addendum. The residual stress distribution on the surface of the tooth profile decreases from the dedendum to the addendum. These findings provide a basis and guidance for the controlled use of residual stress, obtaining better surface layer quality in the high-speed cold roll-beating process of the complex functional profile.

Highlights

  • To obtain a good surface layer performance of the complex functional profile during the high-speed cold roll-beating forming process, this paper analyzed the metal plastic flow and residual stress-formed mechanism by using a theoretical model of the metal flow and residual stress generation

  • A microcorrespondence relationship was established between the metal plastic flow and the residual stress generation. e conclusions indicate that the rate at which the metal flow decreases changes gradually at different metal layers. e residual stress value is directly related to the plastic flow difference

  • Cui et al studied the fiber tissue and the tooth surface hardness distribution of the spline in the process of cold roll-beating through a simulation analysis and experimental observation. e plastic deformation and the phenomenon of surface hardening during the process of cold roll-beating were explained from the microscopic perspective. e effect and properties of metal plastic deformation on the structure were analyzed. e effect of thermomechanical coupling on the metal surface hardening and the effect of forming parameters on the surface roughness of the workpiece in the cold roll-beating process were obtained [8, 9, 17, 18]

Read more

Summary

Model Building

According to the cold rollbeating forming movement process given in [13] and [19], the roll-beating model is simplified by analyzing half of the symmetric model. Relative to the workpiece material (1020 steel), the deformation of the roller with a material of Cr12MoV does not need to be considered in the high-speed cold roll-beating forming process. In this situation, the roller is defined as rigid, according to the movement of the roller. E feed rate of the workpiece is 0.5 mm/s, and different rotational speeds of the roller are set as 188.5 rad/s (1800 r/min) and 235.6 rad/s (2250 r/min) for comparison A surface-to-surface eroding contact is used between the roller and the spline shaft blank. e dynamic and static friction coefficients are set as 0.12 and 0.2, respectively. e hourglass control and volume viscosity are set as the system defaults. e feed rate of the workpiece is 0.5 mm/s, and different rotational speeds of the roller are set as 188.5 rad/s (1800 r/min) and 235.6 rad/s (2250 r/min) for comparison

Simulation Results and Analysis
Experimental Study of Metal Flow and Residual Stress Formation
Discussion
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call