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Improved crystal quality by detached solidification in microgravity
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Wilcox, William R. Regel, Liya L. |
| Copyright Year | 1999 |
| Description | Directional solidification in microgravity has often led to ingots that grew with little or no contact with the ampoule wall. When this occurred, crystallographic perfection was usually greatly improved -- often by several orders of magnitude. Unfortunately, until recently the true mechanisms underlying detached solidification were unknown. As a consequence, flight experiments yielded erratic results. Within the past four years, we have developed a new theoretical model that explains many of the flight results. This model gives rise to predictions of the conditions required to yield detached solidification, both in microgravity and on earth. A discussion of models of detachment, the meniscus models and results of theoretical modeling, and future plans are presented. |
| File Size | 476237 |
| Page Count | 8 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19990040332 |
| Archival Resource Key | ark:/13960/t25b5212g |
| Language | English |
| Publisher Date | 1999-02-01 |
| Access Restriction | Open |
| Subject Keyword | Materials Processing Crystal Growth Directional Solidification Crystals Crystal Surfaces Spaceborne Experiments Czochralski Method Gravitational Effects Space Processing Mathematical Models Ingots Microgravity Bridgman Method Menisci Crystal Structure Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
