A COMPARATIVE-ASSESSMENT OF 3 APPROACHES FOR RANKING THE ADHESION OF TIN COATINGS ONTO 2 STEELS

Three different testing procedures: flexure, micro-indentation and scr atch tests, have been used to compare the adhesion ranking of TiN film s on two steels. Prior to deposition of the TiN film the interface was modified in order to achieve notionally good and bad adhesion of the film. The observations with each technique provide a basis for ranking although the order of ranking was found to change with the different tests. On the basis of these observations it would appear that the fle xure test is the most reliable means for evaluation of the adhesion an d it displays less influence to film thickness than the contact relate d tests. The results are critically discussed and the merits and limit ations of each test presented. (C) 1997 Elsevier Science S.A.