Accession Number:

ADA010885

Title:

The Structure and Mechanical Properties of Internally Oxidized Cu-Ti Polycrystals.

Descriptive Note:

Technical rept.,

Corporate Author:

PITTSBURGH UNIV PA DEPT OF METALLURGICAL AND MATERIALS ENGINEERING

Personal Author(s):

• Greggi,James
• Soffa,William A.
• Meier,Gerald H.

Report Date:

1975-05-19

Pagination or Media Count:

55.0

Abstract:

The structure and mechanical properties of internally oxidized Cu-Ti polycrystals was studied for a range of Ti concentrations and oxidation temperatures. The average TiO2 particle size varied from 76 A for Cu-0.25 wt Ti oxidized at 750 C to 370 A for Cu-1.0 wt Ti oxidized at 1000 C. For oxidation temperatures above 850 C the TiO2 particles had the rutile crystal structure and below 800 C the anatase structure. Between 800 and 850 C the two structures were found to coexist. Orientation relationships with the Cu matrix were found and evaluated for both rutile and anatase particles. The TiO2 dispersion was found to markedly increase the yield strength of Cu and the yield strength data were found to agree well with the predictions of a modified Orowan theory. The alloys exhibited considerable elongation despite the fact that fracture was associated with oxide particles on the grain boundaries.

Descriptors:

• *COPPER ALLOYS
• *DISPERSION HARDENING
• MECHANICAL PROPERTIES
• MICROSTRUCTURE
• OXIDATION
• INTERNAL
• GRAIN STRUCTURES(METALLURGY)
• TITANIUM ALLOYS

Subject Categories:

• Properties of Metals and Alloys

Distribution Statement:

APPROVED FOR PUBLIC RELEASE