| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of manufacturing an exhaust valve for a vessel engine having high durability to bear even a high load in a diesel engine of a large-scale vessel.SOLUTION: The method includes: build-up welding a welding material that consists of a Ni-Cr-Al-system Ni-base age-precipitated alloy overlaying for two or more times to cover the tip of a round steel bar material (S2); then, hot-die forging a tip to shape an umbrella part while adjusting the structure of a welding part (S3); and applying a solution heat treatment (S4) and an age-precipitation heat treatment (S5). |
