Implant with increased carbon content at near-surface boundary layer
Implant in the form of an intraluminal endoprosthesis, having a tubular body containing metallic material, optionally iron, whereby in at least a portion of the implant body the following are present in the structure of a near-surface boundary layer in comparison to the respective concentration in the remaining structure: an increased carbon content in a concentration of approximately 0.5% by weight to approximately 2% by weight; or an increased carbon and nitrogen content, wherein a concentration of carbon is approximately 0.5% by weight to approximately 7% by weight, and a concentration of nitrogen is approximately 0.5% by weight to approximately 17% by weight.
1. An implant in the form of an intraluminal endoprosthesis, having a tubular body containing metallic material, optionally iron, wherein in at least a portion of the implant body the following are present in the structure of a near-surface boundary layer in comparison to the respective concentration in the remaining structure:
an increased carbon content, wherein a concentration of carbon is approximately 0.5% by weight to approximately 7% by weight, and
an increased nitrogen content, wherein a concentration of nitrogen is approximately 5% by weight to approximately 12% by weight.
2. The implant according to claim 1 , wherein the concentration of carbon is approximately 0.5% by weight to approximately 4% by weight.
3. The implant according to claim 1 , wherein the concentration of carbon is approximately 0.5% by weight to approximately 2% by weight.
4. The implant according to claim 1 , wherein the implant has pores in or near the surface.
5. The implant according to claim 1 , wherein the surface of the implant body has, at least in places, tribochemically applied blast particles or a coating which contains a pharmaceutically active substance.
6. The implant according to claim 1 , wherein the body of the implant has a maximum cementite content of approximately 40% by weight in the boundary layer.
7. The implant according to claim 1 , wherein the boundary layer has a maximum thickness of approximately 20 μm.
8. The implant according to claim 1 , wherein the boundary layer has a maximum thickness of approximately 10 μm.
9. The implant according to claim 1 , further comprising a second portion of the body that at least partially adjoins the boundary layer.
10. An implant in the form of an intraluminal endoprosthesis, having a tubular body containing primarily iron or an iron alloy, wherein in at least a portion of the implant body an increased carbon content is present in the structure of a near-surface boundary layer in comparison to the respective concentration in the remaining structure, wherein a concentration of carbon is approximately 0.5% by weight to approximately 2% by weight.
11. The implant according to claim 10 , wherein the body of the implant is greater than 80% by weight iron.
12. The implant according to claim 11 , wherein the body of the implant is greater than 99% by weight iron.
13. The implant according to claim 10 , wherein the implant has pores in or near the surface.
14. The implant according to claim 10 , wherein the surface of the implant body has, at least in places, tribochemically applied blast particles or a coating which contains a pharmaceutically active substance.
15. The implant according to claim 10 , wherein the boundary layer has a maximum thickness of approximately 20 μm.
16. The implant according to claim 10 , further comprising a second portion of the body that at least partially adjoins the boundary layer.
17. An implant in the form of an intraluminal endoprosthesis, having a tubular body containing primarily iron or an iron alloy, wherein in at least a portion of the implant body the following are present in the structure of a near-surface boundary layer in comparison to the respective concentration in the remaining structure:
an increased carbon, wherein a concentration of carbon is approximately 0.5% by weight to approximately 7% by weight, and
an increased nitrogen content, wherein a concentration of nitrogen is approximately 0.5% by weight to approximately 17% by weight.
18. The implant according to claim 17 , wherein the implant has pores in or near the surface.
19. The implant according to claim 17 , wherein the surface of the implant body has, at least in places, tribochemically applied blast particles or a coating which contains a pharmaceutically active substance.
20. The implant according to claim 17 , wherein the boundary layer has a maximum thickness of approximately 20 μm.