THE EFFECT OF GAMMA PRIME PARTICLE SIZE UPON THE HIGH TEMPERATURE PROPERTIES OF NICKEL-BASE ALLOYS
Abstract
The principal conclusions as a result of the investigation, regarding gamma prime-containing NiCr-Al alloys indicate that (1) as the Al content increases, faster cooling rates from above the solution temperature are required to develop maximum room temperature hardness; (2) room temperature hardness, as well as tensile strength and creep strength at elevated temperatures, increase initially with increasing Al; (3) an exhaustion effect is noted, by which the room temperature hardness of high-Al compositions is less sensitive to changes in aging temperature than that of low-Al compositions; (4) very large particle sizes can be readily developed by slow cooling from above the solution temperature; and (5) an optimum-mean-free-path between gamma prime particles exists, which results in minimum creep rate. This optimum-mean-free-path (along with the corresponding particle size for a given volume percent of gamma prime) varies with applied stress. Manganese and titanium expand the lattice of the gamma matrix, and manganese reduces the quantity of gamma prime precipitate. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1960
- Accession Number
- AD0263483
Entities
People
- David L. Sponseller
- R.a. Flinn
Organizations
- University of Michigan