A hybrid friction-induced vibration form: Experimental measurement and mechanism discussion

Friction-induced vibration (FIV) has strong nonlinear properties and complicated mechanism. In this research, the friction characteristics of a block-on-disc system with the variation of the speed are experimentally inves-tigated. At a relatively medium speed, a hybrid vibration form composed of low-frequency stick-slip and high-frequency intermittent unstable vibration is discovered and denoted as stick-unstable sliding. Further, a math-ematical model integrating the negative friction-velocity slope (NFVS) and mode-coupling theories is established to analyze the FIV and noise mechanisms at different speed levels. The results show that the FIV at relatively low and high speeds is respectively affected by the NFVS and mode-coupling. At a relatively medium speed, the NFVS and mode-coupling co-exist and then generate the stick-unstable sliding.

Automated summary

In this research, the friction characteristics of a block-on-disc system with varying speed were experimentally investigated. A hybrid vibration form composed of low-frequency stick-slip and high-frequency intermittent unstable vibration, called stick-unstable sliding, was discovered at a relatively medium speed. Additionally, a mathematical model combining the negative friction-velocity slope (NFVS) and mode-coupling theories was established to analyze the friction-induced vibration (FIV) and noise mechanisms at different speed levels. The results highlight the influence of NFVS and mode-coupling on FIV at different speeds, with the coexistence of NFVS and mode-coupling leading to stick-unstable sliding at a medium speed.