Local microstructural modification in dynamically consolidated metal powders

Autor: W. H. Gourdin
Rok vydání: 1984
Předmět:
Zdroj: Metallurgical Transactions A. 15:1653-1664
ISSN: 2379-0180
0360-2133
DOI: 10.1007/bf02666349
Popis: Powders of 4330V steel, aluminum-6 pct silicon, and copper have been dynamically consolidated under well-characterized conditions using shock waves. Different regions in the final microstructures correlate well with the shock conditions during compaction, demonstrating the importance of the shock history in determining the final microstructure. Martensite is observed to form locally at powder particle surfaces in compacts of 4330V steel, and interparticle melting and rapid re-solidification are observed in compacts of aluminum-6 pct silicon. Microprobe analyses of locally melted regions in the aluminum alloy indicate a homogeneous distribution of 6 pct silicon, well above the maximum equilibrium solid solubility. Comparison with the structure of “splat caps,” found in the starting powder, suggests that locally melted regions experience a cooling rate comparable to that obtained in splat quenching. The extent of martensite formation and local melting are in good agreement with current models for energy deposition at powder particle surfaces during consolidation. The general implications of the analysis and observations are discussed.
Databáze: OpenAIRE