Method for the production of a metallic substrate having a biocompatible surface and substrate produced using same

Abstract

The invention relates to a method for the production of a metallic substrate having a biocompatible surface and to the substrate that is produced by means of said method. The method comprises treatment of a metal, i.e., Ti, Ti alloys with Al, V, Ta, Nb, Ni, Fe, Mo or mixtures thereof, Ta, Ta alloys with Fe, Al, Cr, stainless steel, with a melt of calcium nitrate and an additional component which is an oxygen salt of Na, K, Li, Mg and mixtures thereof, said treatment being effected at 180-480° C. for 0.1 to 12 hours. A substrate is obtained, wherein the overall layer thickness ranges from 10 to below 1600 nm and the fatigue strength of the substrate is in the same fatigue strength range as that of an untreated substrate at equal number of vibrations N.

1 - 7 . (canceled) 
   
   
       8 . A metallic substrate having a biocompatible surface,
 wherein the substrate, being selected from the group consisting of titanium; titanium alloys with aluminum, vanadium, tantalum, niobium, nickel, iron, molybdenum or mixtures thereof;   tantalum; tantalum alloys with iron, aluminum, chromium or mixtures thereof, and stainless steel;   has a reaction layer formed thereon, consisting of an inner oxide layer facing the substrate and an outer Ca-containing layer, the overall layer thickness ranging from 10 to below 1600 nm.   
   
   
       9 . The metallic substrate according to  claim 8 , wherein the outer Ca-containing layer has inclusions of Na, K, Li, Mg atoms or mixtures thereof on its outwardly facing surface. 
   
   
       10 . The metallic substrate with biocompatible surface according to  claim 8 , wherein the Ca-containing layer is a reaction layer integrated in the oxide layer and produced from the reaction of a fused Ca salt with the oxide layer. 
   
   
       11 . The metallic substrate with biocompatible surface according to  claim 8 , wherein the substrate consists of tantalum or of a tantalum-containing alloy and includes a Ca-containing reaction layer, said oxide layer producing a chemical compound with said calcium. 
   
   
       12 . The metallic substrate with biocompatible surface according to  claim 9 , wherein the inclusions of sodium, potassium, lithium or mixtures thereof in the outer Ca-containing layer are present down to a depth of 20% of the layer thickness of the Ca-containing layer. 
   
   
       13 . The metallic substrate according to  claim 8 , wherein in a substrate selected from the group consisting of titanium alloys, tantalum, tantalum alloys, and implant steels, at least in the outer Ca-containing reaction layer, the concentration of the additional alloy metals aluminum, vanadium, niobium, nickel, iron, molybdenum, chromium and mixtures thereof is lower than that inside the substrate by up to 20% by weight, relative to the weight of the alloy metal. 
   
   
       14 . The metallic substrate according to  claim 8 , wherein the layer thickness ranges from 5 to 1600 nm. 
   
   
       15 . The metallic substrate according to  claim 14 , wherein the layer thickness ranges from 10 to 1500 nm. 
   
   
       16 . The metallic substrate according to  claim 14 , wherein the layer thickness ranges from 10 to 800 nm. 
   
   
       17 . The metallic substrate according to  claim 14 , wherein the layer thickness ranges from 20 to 450 nm. 
   
   
       18 . The metallic substrate according to  claim 8 , wherein the fatigue strength of the substrate is in the same fatigue strength range as that of an untreated substrate at equal number of vibrations N.