Date of Award
Spring 1969
Document Type
Thesis - Restricted
Degree Name
Master of Science (MS)
Department
Mechanical Engineering
First Advisor
Jansen, Richard J.
Second Advisor
Hirthe, Walter M.
Third Advisor
Blumenthal, Robert N.
Abstract
The aging and overaging characteristics of 18% Ni (300) maraging steel are studied for aging times of up to twenty weeks at temperatures in the 700°F-1300°F range. The volume fraction of the amount of reverted austenite in overaged samples is determined by both density and magnetic techniques. The effect of austenite content on mechanical properties is observed; specifically, hardness and micro-hardness, impact toughness at the exposure temperature and at room temperature, yield strength and ultimate tensile strength data are determined as a function of heat treatment. The proposed homogenization of samples found to have reached a maximum degree of austenite reversion is investigated by a reaging treatment designed to detect the presence of annealed martensite in the overaged steel. Metallographic examination is conducted with both optical and electron microscopy as a supplementary study. The microstructure of severely banded specimens and other selected samples is discussed.
Recommended Citation
Weston, Leonard A., "The Aging Kinetics and Properties of Isothermally-Transformed Martensite in 18-Nickel 300 Grade Maraging Steel" (1969). Master's Theses (1922-2009) Access restricted to Marquette Campus. 4328.
https://epublications.marquette.edu/theses/4328