Abstract

With new fabrication and measurement technologies now readily available, much attention has been focused on nanostructured materials. The sub-micron scale features of these materials gives them unique physical properties. To understand these properties, conventional methods of materials characterization are not always applicable. Therefore, new methods of characterization are needed for these nanostructured materials. In this project, we have developed nanostructured Cu-Co alloys. Alloys contain 0.3-5.0 wt% cobalt. Alloys are solution-annealed such that the cobalt dissolves in the solid copper phase. By subsequently aging the solid solutions with 1.5% Co at lower temperatures, the cobalt precipitates out of solution and forms precipitate particles with sizes ranging from 0-3 00A. The growth rate of these particles is a function of the aging temperature. These sub-micron sized cobalt particles possess interesting and useful magnetic properties. It was found that the Cu-Co solid solutions behave paramagnetically, with their initial susceptibility being proportional to the square of the cobalt content. For the aged alloys, magnetic methods are used to characterize the material. Using vibrating sample magnetometry, we measured saturation magnetization and coercivity. The saturation magnetization is a function of amount of cobalt that has precipitated out of solid solution. Cobalt concentration in solid solution was also obtained from x-ray diffraction analysis. The coercivity is a function of cobalt particle size and shape distribution. These magnetic particles were also characterized by magnetic force microscopy.

Library of Congress Subject Headings

Magnetic alloys; Nanostructured materials; Nanotechnology

Publication Date

4-7-1997

Document Type

Thesis

Department, Program, or Center

Center for Materials Science and Engineering

Advisor

Gupta, Vinnie

Advisor/Committee Member

Entenberg, Alan

Advisor/Committee Member

Meichle, Linda

Comments

Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works. Physical copy available through RIT's The Wallace Library at: TK454.4.M3 .G374 1997

Campus

RIT – Main Campus

Download

Share

COinS