Ni deposited on HA powder was prepared by electroless plating process without sensitization and activation treatment. The deposited powder obtained was characterized by energy dispersive spectroscopy (EDX) and x-ray diffraction (XRD). The microstructure and hardness of the sintered powder were examined by scanning electron microscopy (SEM) and Vickers hardness respectively. From the result, the nickel existence in the deposition was confirmed by the EDX analysis. The diffraction peaks at 44.5 and 64.7o (2θ) of planes (111) and (211) respectively were belong to nickel. Nickel are homogeneously dispersed in HA matrix with grain size between 0.25-2μm after sintered at 1250°C. The improvement of 93% and 180% in average hardness and flexural strength respectively were achieved with nickel presence in HA compared to pure HA.

Co-HA composite produced using electroless deposition without conventional sensitization and activation treatment was studied with varying sintering temperature (1100°C, 1200°C and 1250°C). The particles size, bulk density, porosity, hardness measurements and the flexural strength are performed in order to find the optimum sintering temperature. After the electroless process for 1 H, the particle size of HA increase to 3.9% and finally the value bulk density percentage of 93.08%, percentage porosity of 6.89%, hardness value of 291.8HV and flexural strength value of 42.4MPa have been achieved after pressing and sintering Co-HA composite at 1250°C. Observations were supporting the idea that Co-HA produced by modified electroless method was improving the mechanical properties with increasing the sintering temperature.

C0-HA composite produced by simple electroless deposition method was studied. From the particle size analysis by Malvern particles analyzer its shows that 19% increment in average of the particle size powder increase after the electroless process with higher cobalt (II) chloride and reduction agent concentration. By EDX and XR-D analysis it was confirmed that cobalt metal was deposited onto HA and contribute to uniform distribution in morphologies by SEM analysis. The Vickers hardness result of up to 430HV was achieved after sintering process at 1250°C. The experimental results demonstrated that the Co-HA powder was successfully prepared by using this method and provide distinct advantages such as uniformity of deposition at lower cost and simple process.

HA-Ni composites were fabricated by uniaxial pressing from coated powders, in which HA particles were successfully coated with nickel precursor by the electroless deposition method. The compacted powders sintered at temperature 1200°C for 1h. Decomposition of hydroxyapatite into α-TCP (α tricalcium phosphate) and TTCP (tetracalcium phosphate) were not occured in any different nickel content before and after sintering. The Ni peaks sharply increased with increasing of Ni content indicate that high crystallinity of metal and confirmed the existence of nickel in the composites. Compared with that of pure HA, the fracture strength of HA inproved by almost 200% by adding 1wt% Ni due to the increase of the composites density. The enhancement in mechanical properties of HA-Ni composites was found to decrease with increase of Ni content, which attributed to the size effect of nickel grains and higher porosity percentage of composites.