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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.

Since the metallic elements are covered with or encapsulated by various plastic or ceramic materials on printed circuit boards (PCBs), a pre-treatment process allowing their liberation and separation is first needed in order to facilitate proficient extraction. In this work, a fundamental study has been carried out to recover metallic concentrates from PCBs scraps. The most important step is to separate or release particles from the associated gangue minerals at the possible liberation particle size. The samples of printed circuit boards were separated into the magnetic and non-magnetic fractions by Rare-earth Roll Magnetic Separator. Then, the magnetic and non-magnetic fractions were separated to heavy fraction (metallic elements) and light fraction (plastic) by Mozley Laboratory Table Separator. Results show that the unliberated particles still remain in the comminution fines PCBs. The use of Rare-earth roll magnetic separation was clarified that the Fe, Ni and Zn element tend to be condensed in magnetic particles. Meanwhile Cu element tends to be release in non-magnetic particles. Mozley Laboratory Table Separation was capable to obtain fractions with relatively high concentrations of metallic elements. This study is expected to provide useful data for the efficient physical separation of metallic components from printed circuit boards scraps.

Ni deposited Hydroxyapatite powder was prepared by electroless deposition technique without sensitization and activation treatments. The composition and phase of deposition were studied. The surface morphologies and composition of initial pure HA powder, as received Ni deposited HA powder and compacted Ni deposited HA powder after sintering were characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) respectively. The phases in the powder before and after sintering were investigated by x-ray diffraction (XRD). From the experiment, with the increase of reduction agent, the plating time becomes shorter and optimal concentration of reduction agent and powder ratio is 3:1. The result shows that Ni succesfully deposited on HA powder and confirmed by EDX result. The Ni grain size distribution of 75nm to 250nm can be clearly observed on the HA surface from the micrograph after sintering. Decomposition of hydroxyapatite into α-TCP (α tricalcium phosphate) and TTCP (tetracalcium phosphate) did not occur in nickel deposited HA before and after sintering. On the other hand, a sharp Ni peak were detected