This page lists works of an author who doesn't have a ResearchGate profile or hasn't added the works to their profile yet. It is automatically generated from public (personal) data to further our legitimate goal of comprehensive and accurate scientific recordkeeping. If you are this author and want this page removed, please let us know.
December 2002
·
2 Reads
·
1 Citation
Journal of Scientific Instruments
An improved apparatus for floating-zone melting by electron bombardment is described. Provision is made for zoning speeds of 0-350 cm/h with bombarding voltages up to 10 kV at 500 mA. The operating vacua are of the order 10-6 mb or better. Up to 22 cm of specimen length can be zoned.
December 2002
·
19 Reads
·
21 Citations
Journal of Scientific Instruments
An apparatus which produces floating liquid zones in vertical rods of refractory metals is described. Movement of the zone along the specimen can purify it in three ways, namely, outgassing on vacuum fusion, evaporation of volatile impurities, and segregation of impurities in the liquid zone. Traversing speeds of approximately 1 cm/min have been used and the vacuum maintained between 10-5 and 5 × 10-4 mb. Power requirements are about 400 W or less. There is a theoretical upper limit of approximately 1 cm on the diameter of a specimen and a practical size limit on its length. Specimens as low as 2 mm in diameter have been zoned. After zoning, many specimens are found to be single crystal.
December 2002
·
88 Reads
·
15 Citations
Proceedings of the Physical Society Section B
The production of molten drops by bombarding the lower end of a vertically suspended rod with electrons has enabled the drop-weight method to be applied to the measurement of the surface tension γ of liquid tungsten. The mean value obtained is 2300 dyn cm-1 at the melting temperature of 3380°C in a vacuum of approximately 10-4 mb.
... The main liquid-phase method for growing tungsten, rhenium, tantalum, molybdenum single crystals is a crucible-free zone melting. As a heating source, an electron beam was originally used (Calverly et al. 1957, Glebovsky 2019. One of the first options for implementing this method is shown in Figure 1a. ...
December 2002
Journal of Scientific Instruments
... For both surface tension and density, results are coherent with the literature review with discrepancies higher than for the tantalum study. It can be noted that for the surface tension, literature values exibit an important scattering (from 2.3 N/m to 2.75 N/m) with the lower values, near our experimental results, being the most reported [5]. Data found in literature for the thermocapillary coefficient −2.9 × 10 −4 N/m/K [3] and −2 × 10 −4 N/m/K [8] are quite close to measure (eq. ...
December 2002
Proceedings of the Physical Society Section B
