Metal treatment – Process of modifying or maintaining internal physical... – Carburizing or nitriding using externally supplied carbon or...
Patent
1992-06-30
1994-08-02
Roy, Uprendra
Metal treatment
Process of modifying or maintaining internal physical...
Carburizing or nitriding using externally supplied carbon or...
148421, 427570, 437 16, 437 18, C22C 1400, C22C 2700
Patent
active
053342640
ABSTRACT:
The present invention relates to ion nitriding of pure titanium or titanium-containing alloys at low pressure by intensifying the glow discharge.
Plasma intensification was produced by thermionic emission in conjunction with a triode glow discharge system. Effective ion nitriding can be achieved by employing the present invention at relatively low temperatures (480.degree. C.) and with significantly enhanced compound layer growth kinetics compared to the conventional nitriding techniques. Processed Ti and Ti-6Al-4V developed a surface layer of TiN followed by a Ti.sub.2 N layer and an interstitial nitrogen diffusion zone. Processed specimens showed a three fold increase in surface hardness. Surface roughness was found to be a function of the degree of plasma intensification. Processing of Ti-6Al-4V resulted in a higher wear, corrosion and wear-corrosion resistance. The present invention indicates that ion nitriding with intensified glow discharge has a great potential as a surface modification method for Ti and Ti alloys. Materials nitriding by the present invention having the properties defined above are suitable for use as orthopaedic implant devices as well as other applications of titanium and titanium alloys requiring resistance to wear and corrosion.
REFERENCES:
patent: 3677832 (1972-07-01), Van Thyne et al.
patent: 4465524 (1984-08-01), Dearnaley et al.
patent: 4664769 (1987-05-01), Cuomo et al.
patent: 4675206 (1987-06-01), Ikegaya et al.
patent: 4948458 (1990-08-01), Ogle
patent: 5156703 (1992-10-01), Oechsner
patent: 5169597 (1992-12-01), Davidson et al.
Rie, K. T., et al. Thermochemical Surface Treatment of Titanium Alloy Ti-6Al-4V by Low Energy Nitrogen Ion Bombardment Materials Science and Engineering, 69 (1985) pp. 473-481.
Meletis, E. I. et al. Formation of aluminum nitride by intensified plasma ion nitriding J. Vac. Sci. Technol. A 9 (4), (1991) pp. 2279-2284.
Metin, E. et al., in Spalvins (Ed.), Characterization of Ion Nitrided Structures of Ti and Ti 6242 Alloy, American Society for Metals, OH, pp. 61-75.
VanderWert, T. L. Surface Modification Technologies III Edited by T. S. Sucdarshan et al., Surface Modification by Magnetic Treatment, The Minerals, Metals & Materials Society, 1990 pp. 393-402.
Metin, R. S. Plasma Surface Treatment of Titanium and Titanium Alloys Light Metal Age (1989) pp. 26-35.
Grill, A. et al. Layer Structure and Mechanical Properties of Low Pressure R.F. Plasma Nitrided Ti-6Al-4V Alloy Surface and Coatings Technology, 43/44 (1990) pp. 745-755.
Raveh, A. et al. Microstructure and Composition of Plasma-Nitrided Ti-6Al-4V Layers Surface and Coatings Technology 38 (1989) pp. 339-351.
Raveh, A. et al. R.F. Plasma Nitriding of Ti-6Al-4V Alloy Thin Solid Films 186 (1990) pp. 241-256.
Raveh, A. et al. Microstructure of Low-Temperature RF Plasma-Nitrided Titanium Alloy Israel Journal Technology 24 (1988) pp. 489-497.
Metin, E. et al. Kinetics of Layer Growth and Multiphase Diffusion in Ion-Nitrided Titanium Metallurgical Transactions A 20A (1989) pp. 1819-1932.
Board of Supervisors of Louisiana State University and Agricultu
Roy Uprendra
LandOfFree
Titanium plasma nitriding intensified by thermionic emission sou does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Titanium plasma nitriding intensified by thermionic emission sou, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Titanium plasma nitriding intensified by thermionic emission sou will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-63128