The effect of long-wavelength stiffness variation on wear pattern generation

In many systems with moving contacts spatially periodic wear patterns related to structural resonances emerge. Often, however, the structural properties of the sliding system vary periodically with position. Based on a generic minimal model the present work investigates the effect of a spatially periodic structural stiffness on wear pattern generation. Linear stability of the resulting wear dynamics is analysed using spatial Floquet analysis. It turns out that the emergence of wear patterns by instability can in general not be evaluated through stability analysis based on spatially local parameters alone. A spatially periodic stiffness can stabilize the system, depending on the wavelength and the amplitude of the spatially periodic parameter variation. The relevance of the effect is discussed and open points are addressed.