New model predicts wear patterns when metal surfaces rub and deform
Researchers have cracked a long-standing problem in predicting how rough surfaces wear when pressed together under stress. The breakthrough could help manufacturers design longer-lasting bearings, seals, and machinery—reducing costly failures and downtime across industries from automotive to aerospace.
Originaltitel: Surface separation in elastoplastic contacts
<p>Understanding the contact between rough surfaces undergoing plastic deformation is crucial in many applications. We study the effect of plastic deformation on the surface separation between two solids with random roughness. Assuming a constant penetration hardness, we propose an iterative smoothing procedure (akin to elastoplastic “shakedown”) within Persson's multiscale contact mechanics theory to obtain the average surface separation by applying the elastic formulation to an effective power spectrum that accounts for plastic smoothing. Deterministic numerical simulations based on the boundary element method are used to validate the procedure and show good agreement with the theoretical predictions. The treatment also provides a route to incorporate plastic stiffening of the roughness as the stress state becomes increasingly hydrostatic at large plastic deformation.</p>