The present invention relates to an exhaust valve structure of a diesel engine for ships,;In the conventional exhaust valve, the material of the head portion and the stem portion is combined with the super heat-resistant alloy steel and the general heat-resistant steel by friction welding method, and thus the adhesion of the coating portion formed on the surface of the exhaust valve is deteriorated due to the different materials. In addition, a problem in which the head part and the stem part are separated due to thermal shock and stress caused by the high temperature and high pressure exhaust gas of the friction welding part has occurred.;Therefore, the present invention for solving the above problems is integrally manufactured by both the head portion and the stem portion of the exhaust valve as a super heat-resistant alloy steel, by the powder welding to melt and paste the super heat-resistant alloy powder to the stem end formed at the end of the stem portion As a result, the head portion and stem portion of the exhaust valve are integrally formed with mode super heat-resistant alloy steel, so that the joint is removed to improve the overall strength of the exhaust valve, and the stem end portion has higher strength and durability than conventional hardening heat treatment of general heat resistant steel. The stiffness is further improved by excellent powder welding, and as the coating is formed on the entire surface of the exhaust valve without foreign parts, the adhesion of the coating is improved, so that the overall durability of the exhaust valve is improved. will be.
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