Improvement of Initial Break-in Condition of Spray Coated Ceramics for Marine Diesel Engine

To avoid separation or abnormal wear of the spray coated ceramics caused by the partial contacting of the initial sliding, it is necessary to improve the initial surface break-in condition of the wear resistant spray coated ceramics of the piston ring and the cylinder linear of the marine diesel engine. The partial contacting wear test of spray coated ceramics was carried out by using pin-on-disk type wear testing machine. The test results of spray coated ceramics with no treatment were compared with that of Ni-P + PTFE plated spray coated ceramics. An observation of wear surface was carried out using together some methods of observation in order to analyze the wear surface in initial break-in condition quantitatively. The main results are in the following: Spray coated ceramics was worn abnormally after partial contacting wear test, but Ni-P + PTFE plated spray coated ceramics was worn normally, protecting from the damage by partial contacting. Phenomenon of surface break-in condition can be evaluated quantitatively by statistical processing of wear surface profile.