Medical implants made of metal alloys bearing cohesive diamond like carbon coatings

A method for coating a titanium base component of a medical implant with diamond-like carbon comprising:

• exposing said component to a vacuum at a pressure of about 10.sup.-5 torr or less;
• heating said component to at least about 600.degree. C.-650.degree. C. (1112.degree.-1202.degree. F.);
• depositing onto said component an intermediate material selected from the group consisting of silicon, germanium, and a combination thereof, in an amount sufficient to form an intermetallic material selected from the group consisting of titanium-silicide, titanium-germanide, and a combination thereof at said outer surface of said substrate cohesively bonded to an interlayer of said intermediate material;
• substantially simultaneous with said depositing of said intermediate material, bombarding said intermediate material with a first energetic beam of ions at a first energy, a first ion arrival ratio, and for a first amount of time sufficient to form said intermetallic bonding layer cohesively bonded to said interlayer;
• condensing a diamond-like carbon precursor onto said interlayer at a second temperature and for a second amount of time sufficient to form a film of precursor molecules on said interlayer, wherein said second temperature is sufficiently low that said diamond-like carbon precursor is not vaporized off of said substrate;
• substantially simultaneous with said condensing of said diamond-like carbon precursor, bombarding said diamond-like carbon precursor with a second energetic beam of ions at a second energy, a second ion arrival ratio, and for a third amount of time sufficient to form a carbide bonding layer selected from the group consisting of silicon-carbide, germanium-carbide, and a combination thereof, cohesively bonded to a coating of diamond-like carbon.

A titanium base component of a medical implant comprising a coating of diamond-like carbon produced by a process comprising:

• exposing said component to a vacuum at a pressure of about 10.sup.-5 torr or less;
• heating said component to at least about 600.degree. C.-650.degree. C. (1112.degree.-1202.degree. F.);
• depositing onto said component an intermediate material selected from the group consisting of silicon, germanium, and a combination thereof, in an amount sufficient to form an intermetallic material selected from the group consisting of titanium-silicide, titanium-germanide, and a combination thereof at said outer surface of said substrate cohesively bonded to an interlayer of said intermediate material;
• substantially simultaneous with said depositing of said intermediate material, bombarding said intermediate material with a first energetic beam of ions at a first energy, a first ion arrival ratio, and for a first amount of time sufficient to form said intermetallic bonding layer cohesively bonded to said interlayer;
• condensing a diamond-like carbon precursor onto said interlayer at a second temperature and for a second amount of time sufficient to form a film of precursor molecules on said interlayer, wherein said second temperature is sufficiently low that said diamond-like carbon precursor is not vaporized off of said substrate;
• substantially simultaneous with said depositing of said intermediate material, bombarding said diamond-like carbon precursor with a second energetic beam of ions at a second energy, a second ion arrival ratio, and for a third amount of time sufficient to form a carbide bonding layer selected from the group consisting of silicon-carbide, germanium-carbide, and a combination thereof, cohesively bonded to a coating of diamond-like carbon.

A titanium base component of a medical implant having an outer surface comprising a sequential gradient as follows:

• an intermediate material selected from the group consisting of silicon, germanium, and a combination thereof, chemically bonded to said titanium in said substrate forming an intermetallic material selected from the group consisting of titanium silicide, titanium germanide, and a combination thereof;
• an interlayer material comprising said intermediate material cohesively bonded to said intermetallic material;
• carbon chemically bonded to said interlayer material, forming a carbide selected from the group consisting of silicon carbide, germanium carbide, and a combination thereof;
• and
• a diamond-like carbon coating cohesively bonded to said carbide.

A solid metal alloy component having an outer surface comprising a sequential gradient as follows:

• a intermediate material selected from the group consisting of silicon, germanium, and a combination thereof, chemically bonded to said metal alloy in said substrate forming an intermetallic material selected from the group consisting of a metal-silicide, a metal-germanide, and a combination thereof;
• an interlayer comprising said intermediate material cohesively bonded to said intermetallic material;
• carbon chemically bonded to said interlayer material, forming a carbide selected from the group consisting of silicon carbide, germanium carbide, and a combination thereof;
• and
• a diamond-like carbon coating cohesively bonded to said carbide.

A solid metal alloy component coated with diamond-like carbon by a process comprising:

• exposing said component to a vacuum at a pressure of about 10.sup.-5 torr or less;
• heating said component to a first temperature of about 300.degree. C. (149.degree. F.) or, if said metal alloy is temperature sensitive, to a highest temperature acceptable for said metal alloy;
• depositing onto said component an intermediate material selected from the group consisting of silicon, germanium, and a combination thereof in an amount sufficient to form an intermetallic material selected from the group consisting of a metal-silicide, a metal-germanide, and a combination thereof at an outer surface of said component cohesively bonded to an interlayer of said intermediate material;
• substantially simultaneous with said depositing of said intermediate material, bombarding said intermediate material with a first energetic beam of ions at a first energy, a first ion arrival ratio, and for a first amount of time sufficient to form said intermetallic bonding layer cohesively bonded to said interlayer;
• condensing a diamond-like carbon precursor onto said interlayer at a second temperature and for a second amount of time sufficient to form a film of precursor molecules on said interlayer, wherein said second temperature is sufficiently low that said diamond-like carbon precursor is not vaporized off of said substrate;
• substantially simultaneous with said condensing of said diamond-like carbon precursor, bombarding said diamond-like carbon precursor with a second energetic beam of ions at a second energy, a second ion arrival ratio, and for a third amount of time sufficient to form a carbide bonding layer selected from the group consisting of silicon-carbide, germanium-carbide, and a combination thereof cohesively bonded to a coating of diamond-like carbon.