Pressure and temperature control in flat-belt type high pressure apparatus for reproducible diamond synthesis

• Published in: Diamond and related materials Vol. 8; no. 11; pp. 2036 - 2042
• Main Authors: Fukunaga, O., Ko, Y.S., Konoue, M., Ohashi, N., Tsurumi, T.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.11.1999; Elsevier
• Subjects: Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Flat-belt apparatus; Growth from melts; zone melting and refining; High pressure diamond synthesis; Materials science; Methods of crystal growth; physics of crystal growth; Minimum pressure and temperature of diamond formation; Physics; Pressure and temperature measurements; High pressure diamond synthesis; Flat-belt apparatus; Pressure and temperature measurements; Minimum pressure and temperature of diamond formation; Compression; Synthetic mineral; Process control; Diamonds; Instrumentation; Pressure control; High temperature; Very high pressure; High pressure; Crystal growth habit; Nonmetals; Morphology; Temperature control; Crystal growth from melts
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/S0925-9635(99)00171-5

This paper describes a technique on the pressure and temperature control in flat-belt (FB) type high pressure apparatus to conduct stable diamond synthesis study. We present results on the reproducibility of the sample pressure and temperature in different sets of diamond synthesis runs. We propose a method of monitoring these variations by the measurements of anvil displacement as a function of press load, and of heater resistance as a function of input power to the heater in every high pressure run. We examined pressure and temperature region of diamond formation in graphite-solvent metal systems, and propose a method to estimate the absolute pressure and temperature of the sample based on the graphite–diamond equilibrium curve. From these data, we conclude that the pressure and temperature of the sample in FB type high pressure apparatus can be estimated and controlled within about 3%.