The Effect of Non-Stoichiometry on the Structure of La-Ni and La-Ni-Ga Alloys

Author

Pertrice Auguste Wethey

Date of Award

12-2003

Degree Name

Master of Science

Department

Mechanical and Aerospace Engineering

First Advisor

Dr. Ari-Gur

Second Advisor

Dr. Bliznyuk

Third Advisor

Dr. Atashbar

Access Setting

Masters Thesis-Open Access

Abstract

Non-stoichiometric samples of the AB₅ system defined by the formula La_1-yNi_5+2y and LaNi_5+2xGa_1-x were cast using an arc-melting furnace. The samples were then analyzed to determine their lattice parameters and phases present using XRD. They were then heat-treated to produce homogeneous compounds and quenched with the intention of retaining high temperature compositions. Following the heat-treatment, the alloys underwent XRD again as well as SEM/EDS. The XRD information was analyzed using Rietveld refinement and the elemental data derived from the EDS was used to ascertain the compositions were statistically akin to the weighed values. The Micrographs were used to determine what happened to the compound during heat-treatment and whether that step is in fact necessary.

Recommended Citation

Wethey, Pertrice Auguste, "The Effect of Non-Stoichiometry on the Structure of La-Ni and La-Ni-Ga Alloys" (2003). Masters Theses. 1404.
https://scholarworks.wmich.edu/masters_theses/1404