Steam turbine rotor blade having erosion resistance, manufacturing method thereof, and steam turbine using the same

摘要

PROBLEM TO BE SOLVED: To provide a steam turbine moving blade with superior erosion resistance, and a method of manufacturing the same, and a steam turbine using the same.SOLUTION: A steam turbine moving blade with erosion resistance has a blade tip portion, which is at least hardened, of the steam turbine moving blade, and the moving blade is made of precipitation hardened type martensitic steel and is characterized in that a remaining amount of the blade tip portion is lower than that of a blade base material portion. The moving blade is obtained by subjecting the whole blade to a solution treatment at 850-1,000°C, holding the blade tip portion locally at 850-1,100°C (first temperature) and then continuously holding the blade tip portion at 500-750°C (second temperature), cooling the blade tip portion down to room temperature or below, and lastly subjecting the whole blade to aging treatment at a temperature of 500-650°C below the second temperature.