In this work, carbonated hydroxyapatite (CHA) based on abalone mussel shells (Haliotis asinina) is synthesized using the co-precipitation method. The synthesized CHA was mixed with honeycomb (HCB) 40 wt.% for the scaffold fabrication process. CHA and scaffold CHA/HCB 40 wt.% were used for coating a Titanium (Ti) alloy using the electrophoretic deposition dip coating (EP2D) method with immersion times of 10, 20, and 30 min. The synthesized B-type CHA with a stirring time of 45 min could have lower transmittance values and smaller crystallite size. Energy dispersive X-ray spectroscopy (EDS) showed that the Ca/P molar ratio was 1.79. The scaffold CHA/HCB 40 wt.% had macropore size, micropore size, and porosity of 102.02 ± 9.88 μm, 1.08 ± 0.086 μm, and 66.36%, respectively, and therefore it can also be applied in the coating process for bone implant applications due to the potential scaffold for bone growth. Thus, it has the potential for coating on Ti alloy applications. In this study, the compressive strength for all immersion time variations was about 54–83 MPa. The average compression strengths of human cancellous bone were about 0.2–80 MPa. The thickness obtained was in accordance with the thickness parameters required for a coating of 50–200 μm.

In this study, hydroxyapatite (HA) from abalone mussel shells (Haliotis asinina) is synthesized using the precipitation method with a stirring time of 30 min and a calcination temperature of 1000°C. HA was used for coating Ti alloy using the electrophoretic deposition dip coating (EP2D) method. The coating applied three variations, including the DC voltages variation of 25 V and 50 V, the withdrawal speeds of 0.1 mm/s, 0.5 mm/s, 1 mm/s, and the calcination temperatures of 750°C and 950°C. Energy dispersive X-Ray spectroscopy (EDS) revealed the Ca/P molar ratio of HA was 1.63, which is close to the stoichiometric ratio of HA at 1.67. The distance between the crystal planes of the HA was 2.81Å. This result also is relative to the crystal plane of the HA at 2.88Å. The EP2D process and the calcination temperature treatment will remove the B-type carbonate apatite phase, so the purity of the HA layer is higher. SEM results show that the HA layer formed was more homogeneous and thicker at the DC voltage of 50 V and the withdrawal velocity of 0.1 mm/s. At this voltage and velocity, minor cracking and agglomeration were produced. The density of the HA layer was higher with increasing calcination temperature and DC voltages. Keywords: Hydroxyapatite, Titanium Alloy, Coating, Electrophoretic Deposition Dip Coating