Nano structure hydroxyapatite/titanium composite coating and preparing method thereof

Abstract

The invention provides a preparing method of a nano structure hydroxyapatite / titanium composite coating, and belongs to the technical field of coating preparing. The nano hydroxyapatite and titanium are mixed to form composite particle suspension liquid, and the proportion of the hydroxyapatite to the titanium can be adjusted at will; after the composite particle suspension liquid is mixed with atomization gas, the mixture enters a supersonic speed flame spray gun through micro holes, the temperature of mixed particles in flames is reduced, compared with conventional supersonic speed flame spraying, a solvent wrapping the peripheries of the mixed particles can absorb part of heat through volatilization, and thermal decomposition or non-crystallizing of a nano hydroxyapatite particle phasestructure is avoided; the nano hydroxyapatite and the titanium particles are sufficiently mixed in the suspension liquid, and uniformity of two phases in the composite coating is improved; part of thetitanium particles and titanium particle surface layers are oxidized in oxygen containing high-temperature flames, the problem about thermal expansion mismatching between the hydroxyapatite and the titanium particles can be solved through titanium particle oxide, the titanium particle oxide can serve as a reinforcing phase to exist in the composite coating, and the hardness and elasticity modulusof the composite coating are improved.

Description

technical field [0001] The invention relates to the technical field of coating preparation, in particular to a nanostructured hydroxyapatite / titanium composite coating and a preparation method thereof. Background technique [0002] As a hard tissue implant material, medical metal has the advantages of high fatigue strength and long service life compared with medical ceramics and polymer materials. However, metal materials have low surface activity and even release toxic ions in the body, which limits their clinical application. Hydroxyapatite is used as a hard tissue implant material because it has the same chemical composition as human bone inorganic matter, high biological activity and can induce cell regeneration. The preparation of hydroxyapatite composite coating on the surface of medical metal can take advantage of the excellent mechanical properties of metal materials and the high biological activity of hydroxyapatite. Due to the low strength and high brittleness of...

AI Technical Summary

Problems solved by technology

[0005] Although cold spraying method, electrodeposition method and sol-gel method can avoid thermal decomposition and chemical reaction of nano-hydroxyapatite powder phase structure, the nano-hydroxyapatite used in the formation of titanium / hydroxyapatite composite coating by cold spraying method The composition ratio of the mixed powder of titanium and pure titanium is strictly required. If the proportion of titanium particles is too low, it will be difficult to form a composite coating; the electrodeposition method and the sol-gel method have the problem of high-temperature thermal decomposition of the hydroxyapatite phase structure in the subsequent heat treatment process.

The electrodeposition method also has the problems of polluting the environment and causing human injury due to the use of toxic chemical reagents

In addition, the use of mechanically mixed powders of heterogeneous phase particles to prepare coatings has the problem of uneven distribution of heterogeneous phases in the coating, which leads to poor stability of mechanical properties of the coating.

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