Effect of High-Temperature Annealing in Vacuum and Hydrogen on Paramagnetic Defects in Diamond Films Grown by Chemical Vapor Deposition

Thin diamond film coated WC-Co cutting tool inserts were produced using arc-jet and hot-filament chemical vapor deposition. The diamond films were characterized using SEM, XRD, and Raman spectroscopy to examine crystal structure, fracture mode, thickness, crystalline orientation, diamond quality, and residual stress. The performance of the tools was evaluated by comparing the wear resistance of the materials to brazed polycrystalline diamond-tipped cutting tool inserts (PCD) while machining A390 aluminum (18% silicon). Results from the experiments carried out in this study suggest that the wear resistance of the thin diamond films is primarily related to the grain boundary strength, crystal orientation, and the density of microdefects in the diamond film.

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Heteroepitaxial AlN growth 4on c-plane sapphire substrates by ammonia-free high temperature metalorganic chemical vapor deposition

Journal of Crystal Growth ◽

10.1016/j.jcrysgro.2021.126496 ◽

2022 ◽

pp. 126496

Author(s):

Xu-Qiang Shen ◽

Kazutoshi Kojima

Keyword(s):

Chemical Vapor Deposition ◽

High Temperature ◽

Vapor Deposition ◽

Metalorganic Chemical Vapor Deposition ◽

Chemical Vapor ◽

Sapphire Substrates ◽

Metalorganic Chemical

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The Progress on Low-Cost, High-Quality, High-Temperature Superconducting Tapes Deposited by the Combustion Chemical Vapor Deposition Process

MRS Proceedings ◽

10.1557/proc-689-e7.8 ◽

2001 ◽

Vol 689 ◽

Author(s):

Shara S. Shoup ◽

Marvis K. White ◽

Steve L. Krebs ◽

Natalie Darnell ◽

Adam C. King ◽

...

Keyword(s):

Chemical Vapor Deposition ◽

High Temperature ◽

Critical Current Density ◽

Buffer Layer ◽

Critical Current ◽

Vapor Deposition ◽

Low Cost ◽

Chemical Vapor ◽

High Critical Current Density ◽

High Quality

ABSTRACTThe innovative Combustion Chemical Vapor Deposition (CCVD) process is a non-vacuum technique that is being investigated to enable next generation products in several application areas including high-temperature superconductors (HTS). In combination with the Rolling Assisted Biaxially Textured Substrate (RABiTS) technology, the CCVD process has significant promise to provide low-cost, high-quality lengths of YBCO coated conductor. The CCVD technology has been used to deposit both buffer layer coatings as well as YBCO superconducting layers. A buffer layer architecture of strontium titanate and ceria have been deposited by CCVD on textured nickel substrates and optimized to appropriate thicknesses and microstructures to provide templates for growing PLD YBCO with high critical current density values. The CCVD buffer layers have been scaled to meter plus lengths with good epitaxial uniformity along the length. A short sample cut from one of the lengths enabled high critical current density PLD YBCO. Films of CCVD YBCO superconductors have been grown on single crystal substrates with critical current densities over 1 MA/cm2. Work is currently in progress to combine both the buffer layer and superconductor technologies to produce high-quality coupons of HTS tape made entirely by the non-vacuum CCVD process.

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