Pest Reactions in Intermetallic Compounds II. Investigations on NiAl, and Two MoSi2 Structures

Item

Title
Pest Reactions in Intermetallic Compounds II. Investigations on NiAl, and Two MoSi2 Structures
Date
1964
Index Abstract
Not Available
Photo Quality
Incomplete
Report Number
ASD-TDR-63-309 Part II
Creator
Syebolt, A. U.
Westbrook, J. H.
Corporate Author
General Electric Research Labpratory
Laboratory
Directorate of Materials and Processes
Extent
38
Access Rights
OTS
Distribution Classification
1
Contract
AF 33(657)-7980
DoD Project
7350
DoD Task
735001
DTIC Record Exists
Yes
Distribution Conflict
No
Abstract
The grain boundary hardening phenomena investigated earlier in the case of the intermetallic compound NiGa have been found to occur in much the same manner in NiAl. As before, an oxygencontamination heat treatment followed by a sufficiently high temperature quench shows no hardening, but subsequent lower temperature aging sets up hardening. Hardening occurs in the bulk as well as along grain boundaries, but generally the effect is harder to observe in the former case because of shallow oxygen penetration in the bulk as compared to the grain boundaries. A vacancy-oxygen atom interaction model is suggested as a likely explanation for the observed hardening. Some observations have been made on pest failure in MoSi2, and grain boundary hardening in the structural analog CrAl2. It is difficult to find suitable experimental techniques to study the pest failure of MoSi2. As-cast material is more susceptible to pest failure than MoSi2 coatings on molybdenum sheet.
Report Availability
Full text available by request
Identifier
AD0439216
Date Issued
1964-04
Provenance
Bearcat
Type
report
Format
38 pages ; 28 cm.