Abstract
Electron microstructures, precipitates and fracture surface characteristics of Ni-Co-Cr-Fe alloy (Refractaloy 26 type) and Ni-Cr alloy (Inconel X type) for spring at high temperature service are investigated.
These alloys that are optimumly aged in order to get superior properties for spring at high temperature services, are observed for the microstructures, precipitates and fracture surface characteristics with transmission electron microscope and scanning electron microscope. Precipitates, which are the cause of precipitation hardening, are diffracted with X-ray.
The contents of study are as follows;
(1) Effects of aging on the microstructure and precipitate.
(2) Relation between the misfit percent of γ′ to matrix and the rate of increase in hardness.
(3) Effect of aging on the size of γ′.
(4) The measurement of hardness of the γ′ and matrix at high temperature.
(5) Effect of the precipitate on fracture surface characteristics.
