Relaxation of residual stresses in brush-plated gold and silver coatings on copper and on brass substrates

摘要

The investigated brush-plated gold and silver coatings are used for refining the surface properties of electric apparatuses. Tensile residual stresses generated in the plated coatings were determined by the curvature method and by instrumented indentation testing of a thin-walled open ring substrate, as described in our earlier papers. These stresses relax over time and their dependence on relaxation time was approximated by a linear-fractional function. The Young's modulus and nanohardness of the coatings were determined. The surface morphology and structure in cross section of the coated substrates were presented.