|JURASZ Zbigniew||Bosmal Automotive Research and Development Institute Ltd.|
|Spoluautoři ADAMASZEK Krzysztof|
The corrosion resistance of widely used X50CrMnNiNbN21-9 high-alloyed austenite valve steel in three different combustion gases have been compared. The comparison was performed on the basis of results of kinetic corrosion of the tested steel in combustion gases from propane-butane, gasoline with 5 and 10 % of ethanol additives (v/v) and fuel oil with 5 and 10 % of FAME additives (v/v). The corrosion test was performed gravimetrically under thermal shock conditions by heating samples of the test steels from room temperature up to 1173 K in exhaust gases from a combustion engine, and holding them at this temperature for 2 hrs. and then cooling at room temperature for about 25 min. Then the same thermal shock was repeated and after every 10 to 20 such cycles the mass of the specimens were measured. This experiment simulated the working conditions of a highly thermal loaded exhaust valves in spark or self-ignited combustion engines. The analysis performed shows that the corrosion resistance of X50CrMnNiNbN21-9 valve steel in an environment of combustion gases from propane-butane and gasoline with 5 and 10 % of ethanol additives (v/v) is comparable, whereas significantly worse corrosion resistance was stated in an environment of combustion gas from fuel oil with 5 % and 10 % (v/v) of FAME additives.