Method for preparing continuous gradient biological coating by utilizing suspension plasma spraying

Abstract

The invention discloses a method for preparing a continuous gradient biological coating by utilizing suspension plasma spraying. A calcium silicate / fluorohydroxyapatite continuous gradient biologicalcoating is prepared on the surface of a titanium or titanium alloy matrix by utilizing a suspension plasma spraying method. The high bonding strength between a calcium silicate coating and the titanium matrix and the low solubility of fluorohydroxyapatite are utilized, solid phase components of a mixed solution are gradually changed by adjusting the liquid feeding rates of two suspensions, the continuous gradient coating is prepared on the surface of the titanium or titanium alloy matrix by adopting a suspension plasma spraying technology, namely, the calcium silicate is arranged at the bottomof the coating, the fluorohydroxyapatite is arranged at the top of the coating, gradient component transition is achieved between the top and the bottom, the internal stress of the coating can be greatly reduced through gradient design, and the sensitivity at an interface is reduced. The binding force between the calcium silicate / fluorohydroxyapatite gradient coating and the titanium matrix is obviously improved, the dissolution rate is obviously reduced, and the coating shows good biological activity and antibacterial activity.

Description

technical field [0001] The invention relates to the technical field of biological coatings. Specifically, it is a method for preparing continuous gradient biological coatings by plasma spraying of suspensions. Background technique [0002] The use of plasma spraying technology to prepare hydroxyapatite biocoatings on the surface of titanium substrates has been applied clinically. However, the problem is that the thermal expansion coefficient of the hydroxyapatite coating and the titanium substrate is quite different, and there is a high residual stress inside the coating, resulting in a low bonding strength between the coating and the substrate; during the spraying process of hydroxyapatite The generated amorphous phase dissolves under physiological environment, which makes the stability of the coating relatively poor and affects the long-term stability of the implant. Therefore, improving the bonding strength of the coating and reducing the dissolution rate of the coating...

AI Technical Summary

Problems solved by technology

However, the coating degrades too quickly in a physiological environment, and it is often necessary to introduce a second phase with a lower degradation rate to form a silicate compound with a relatively stable structure.

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