Effect of Frictional Heat Accumulation on Damage Initiation of M50 Steel at Cyclic Sliding Contact

The effect of frictional heat accumulation on the surface damage initiation at cyclic sliding contacts of M50 steel is investigated. The surface damage is detected by a sudden increase in the frictional coefficient during the ball-on-disk sliding contact test. The periodically thermal response of the rotating disk during tests is correspondingly calculated by using a numerical method based on Fourier transform. The results show that while the final failure mode is consistent under fixed pressure and velocity, the time to failure is controlled by the heat accumulation rate, which is highly sensitive to cyclic frequency. A smaller rotational radius increases contact frequency and reduces heat dissipation within a single cycle, accelerating temperature rise and surface damage initiation. The parametric analysis revealed the distinct effects of contact pressure, sliding velocity, and friction coefficient on frictional heat flux and heat dissipation. The study concludes that controlling heat accumulation behavior is critical for predicting and mitigating surface damage at cyclic sliding contact.