Zobrazeno 1 - 10
of 41
pro vyhledávání: '"Robert J. Waltman"'
Autor:
Robert J. Waltman
Publikováno v:
Tribology Online, Vol 14, Iss 2, Pp 41-52 (2019)
The diffusion of oxidized cobalt metal (CoOx) through a sputtered amorphous carbon film is investigated as a function of carbon film thickness and of temperature in dry air. A kinetic model is developed using the experimental data. The kinetic model
Externí odkaz:
https://doaj.org/article/2245b4b64cea4b33a30b85889300320d
Publikováno v:
Tribology Online, Vol 13, Iss 5, Pp 262-274 (2018)
Star PFPE (perfluoropolyether) polymers based on an aromatic benzene core and a non-aromatic cyclotriphosphazene (CTP) core are investigated as boundary lubricant films on rigid magnetic media. The effect of the benzene and CTP cores on head-disk spa
Externí odkaz:
https://doaj.org/article/4e45e1742dec4b2bb118c130cb5cb729
Autor:
Robert J. Waltman
Publikováno v:
Tribology Online, Vol 11, Iss 4, Pp 503-511 (2016)
Lubricant reflow for 10 Å Z-Tetraol film is characterized for heat-assisted magnetic recording by numerical simulation using the experimentally determined thickness-dependent diffusion equation. The competition between laser-induced lubricant deplet
Externí odkaz:
https://doaj.org/article/89ae944039f94866b958128b72761f1a
Autor:
Robert J. Waltman
Publikováno v:
Tribology Online, Vol 11, Iss 1, Pp 50-60 (2016)
Lubricant reflow for Z-Tetraol is characterized for heat-assisted magnetic recording (HAMR). The thickness-dependent diffusion constant, D(h), is determined from flow experiments for submonolayer Z-Tetraol films between 2.5 and 13 Å. Fickian diffusi
Externí odkaz:
https://doaj.org/article/8d4232d1b0a042d4a37ec2574f2866c6
Autor:
Robert J. Waltman
Publikováno v:
Tribology Online, Vol 9, Iss 2, Pp 51-62 (2014)
Infrared specular reflection spectra of the TA-30, D-4OH and C4-4OH perfluoropolyether liquid films on gold substrates are simulated and studied experimentally. The simulated spectra were obtained using a classical dispersion analysis coupled with so
Externí odkaz:
https://doaj.org/article/fd6419d83a1d4a6492d8877d8987650e
Publikováno v:
Tribology Online, Vol 8, Iss 3, Pp 250-256 (2013)
Slider-disk contact hysteresis is investigated as a function of the Zdol bonded fraction at constant film thickness. The contact hysteresis is found to increase with the Zdol bonded fraction. AFM force-distance curves also indicate increasing work of
Externí odkaz:
https://doaj.org/article/e39e12dcb23d46158212754fa6e2d219
Publikováno v:
Tribology Online, Vol 7, Iss 2, Pp 70-80 (2012)
The UV irradiation of Z-Tetraol films on amorphous nitrogenated carbon surfaces was investigated. COF2 evolution, captured in the gas phase, decreased with increasing number of OH end groups in the order: Z > Zdol > Z-Tetraol after UV irradiation. Bo
Externí odkaz:
https://doaj.org/article/e6a60ff82811452d8cb02f99c0d5b60b
Publikováno v:
Tribology Online, Vol 7, Iss 1, Pp 41-45 (2012)
The thin film properties of some novel branched perfluoropolyether (PFPE) boundary lubricants are investigated as a function of molecular polarity and end-group bonding to the underlying carbon film. The PFPE main chain, comprised of n-perfluoroethyl
Externí odkaz:
https://doaj.org/article/6641fee997574b8aaf3f522df30a0d3e
Publikováno v:
IEEE Transactions on Magnetics. 47:239-243
Ever decreasing magnetic spacing in the hard disk drive requires each contribution to the magnetic spacing to be examined for possible reduction. Currently, the lubricant layer on top of the disk carbon overcoat is typically 10-20 Å thick. This pap
Publikováno v:
Tribology Letters. 12:163-169
The dewetting of perfluoropolyether (PFPE) films on amorphous nitrogenated carbon, CNx, is investigated. An optical surface analyzer is used to image perfluoropolyether films on CNx-overcoated magnetic recording disks. An autophobic dewetting transit