High Performance Heavy Alloys by Alloying and Process Control
Abstract
The kinetics and processing conditions of liquid phase sintering (LPS) have been addressed in the development of a novel heavy alloy, W-Ni-Mn. Solubility criteria were considered in the selection of manganese as an alloying element to the W-Ni system. The addition of manganese resulted in a depressed melting point of the matrix and consequently sintering in this system was achieved at temperatures 300 deg C lower than in the conventional heavy alloys. Concurrent with solubility criteria, the rearrangement stage in liquid phase sintering was treated. When capillary and viscous drag forces are accounted for, the time scales in rearrangement were found to be in the microseconds range for metal systems. On the other hand, heat transfer was found to be the rearrangement time limiting factor for metallic specimens with time scales in the range of seconds. Further, depending on the green density and the system under consideration, there exists specific specimen dimensions where a transition from heat transfer to capillary control over the rearrangement time. These dimensions are, however, in the micrometer range. Tungsten heavy alloys, Grain growth, Alloying, Mechanical properties, Microprobe analysis.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 22, 1993
- Accession Number
- ADA271129
Entities
People
- A. Belhadjhamida
- R. M. German
Organizations
- Pennsylvania State University