Non-destructive test for the quality of zinc phosphate coating on a metal work piece e.g. brake components

摘要

In a production line process to test the quality of a zinc phosphate coating on a metal work piece, the work piece is submerged in a vat containing a mixture of desalinated water, sulphuric acid and copper sulphate. After removal from the vat the work piece is then thoroughly rinsed with desalinated water, followed by drying and examination of the exposed surface to detect possible corrosion. Also claimed is a commensurate test assembly.