MEASUREMENT OF MAR RESISTANCE AND STUDY OF MARRING MECHANISM OF POLYMERIC COATINGS WITH SCANNING PROBE MICROSCOPE

摘要

We have used a scanning probe microscope (SPM), equipped with a custom-made probe, consisting of a diamond tip and rectangular tungsten cantilever, to measure the mar resistance of cross-linked polymeric surface coatings, a very desirable characteristic of the coatings, at micron and submicron scales. With the unique high resolution of SPM, the dimension of the mars can be measured with great accuracy, thus different responses of coatings to the marring stress, i. e. elastic recovery, plastic deformation, and abrasive wear, can be identified quantitatively. In addition, the dynamic process of marring, including viscoelastic creep, strain-hardening, micro-cracking, and surface fatigue, has also been studied with the SPM.