Resumen de Analysis of valve and valve seat insert damage morphology observed after different engine test

Alejandra Zuleta, F Mazuco, A. Sinatora, D.K. Tanaka

• This paper presents visual examination results and topographic analysis of two 8-valves engines intake and exhaust valves and valve seats in order to characterize wear damages as part of the “FAPESP – Desafios tribológicos em motores Flex-Fuel – TRIBOFLEX” project. One of the engines was tested in dynamometer through thermal shock test, operated from idle to full load regime. The other engine was tested using conventional vehicle in injection system test. The terminology used to describe observed damages was not lined up with the commonly used designations in the literature, to avoid preconceived ideas of the damage. The damage was documented using scanning electron microscopy (SEM) with an energy-dispersive Xray spectroscopy (EDS) and photographically using optical microscopy (OM). Many damages were observed in both: intake and exhaust valves of both engines, although some damages, such as oxidation, was observed only in the exhaust valves. The damages characterized as: ...