04693760 is referenced by 55 patents and cites 4 patents.

A process for preventing surface discoloration in orthopedic implants made of titanium and its alloys is disclosed. Such surface discoloration is apt to occur when the orthopedic implants are ion implanted to improve their wear characteristics. The process essentially includes exposing all fixtures and shields, made of pure titanium, located in an implant chamber, to an ion beam, creating a vacuum within the chamber not exceeding about 5.times.10.sup.-5 torr, introducing an orthopedic implant within the chamber to be directly exposed to the beam, and reducing the ion beam current power density so as not to exceed about 1.0 watt/cm.sup.2. Exposing the fixtures and shields to the ion beam first serves to remove surface contamination therefrom, followed by forming a surface layer thereon. This surface layer effectively lowers the sputtering coefficient of the fixtures and shields, and thus reduces the amount of material sputtered from areas exposed to the ion beam to unexposed areas. Preferably, the vacuum is created by using an oil-free vacuum pump.

Title
Ion implanation of titanium workpieces without surface discoloration
Application Number
6/861845
Publication Number
4693760
Application Date
May 12, 1986
Publication Date
September 15, 1987
Inventor
Piran Sioshansi
Bedford
MA, US
Agent
Morse Altman & Dacey
Assignee
Spire Corporation
MA, US
IPC
C23C 11/10
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