Electrophoretic Deposition of Hydroxyapatite Coatings on AZ31: The Effect of Nanoparticle Multiple Coating Approach

Magnesium and its alloys are potential biodegradable implant materials. However, they are characterized by rapid degradation in the electrolytic environment of the body. This phenomenon might result a sudden implant failure before bone restoration was complete, or inflammation subsided. This research will explore ways to improve the corrosion resistance of AZ31 magnesium alloy by improving the coating layer of hydroxyapatite (HA) through multiple coating layers by an electrophoretic deposition (EPD) process. In this study, the quality of the coating layer was improved by multiple coating processes without using any binders. X-ray diffraction spectrometer (XRD) showed that an amorphous structure of HA was successfully deposited on the AZ31 alloy. Scanning electron microscopy (SEM) has been used to observe that the morphology of the AZ31 alloy coated with multiple layers of HA has a denser coating structure with improved adhesion at the interface as compared to the single coating layer. A denser coating structure with greater bonding between the coating layer and the substrate is expected to protect the substrate from a high corrosion rate, thus resulting in a longer period of biodegradation as in implant in the electrolytic environment.

Study on New Adiabatic Multiple Layer Coating for Metal Mold

The new adiabatic multiple coating is composed of surface coating and ground coating. The main raw material of surface coating is diatomite and that of ground coating is zircon powder. This paper separately study on the formula of the surface and ground coating. The results show that the adiabatic and other properties of composite coating are good and the coating can be used on the metal mold to cast the ferritic nodular cast iron (ferrite% ＞95%). And the using life of metal mold is improved.

Preparation of Color Pearlescent Pigment Using Rare-Earth Oxide and Titanium Oxide to Coat Mica

The rare earth of Er2O3, Nd2O3, Pr6O11 as pigmentation-type coating materials was used to coat the surface of mica by wet chemical deposition method. Then the color pearl luster pigment was synthesized by heat treatment. The coating was carried out by multiple-coating technique and the influence of technique parameters on the coating was studied systematically.

The Influence of PZT Film Thickness on Microstructure in CSD Processing

The R&D of state of the art PZT (PbZrxTi1-xO3) films is important due to their piezoelectric, pyroelectric and ferroelectric properties. Currently, Chemical Solution Deposition (CSD) methods (e.g. spin coating of a sol-gel precursor solution) are successfully used in our lab to deposit PZT films with intermediate thickness. This method employs multiple coating procedures and different microstructure is observed after each coating. We report on the film microstructure evolution studied by quantitative analysis of HRSEM images as a function of thickness.