Experimental Study on Ca3(PO4)2-Al2O3 Bio-ceramic Composite Using DPSS Laser

Abstract

The DPSS lasers are mostly used in industries for laser based micromachining. The present experimental study investigates the laser micro grooving operation on a sheet of Calcium phosphate-Alumina (Ca3(PO4)2-Al2O3) bio-ceramic composite for bio-medical applications. The Ca3(PO4)2-Al2O3 bio ceramic has been fabricated by adding 20% weight of alumina with calcium phosphate to enhance the mechanical properties of the bio-ceramics. Bio ceramics were initially used as alternatives to metals to increase their biocompatibility. Ca3(PO4)2-Al2O3 bio ceramics shows the properties like bioactive and bio resorbable compounds.. Pulse frequency, pulse width, diode current and gas pressure has been taken as input parameters. Upper width, lower width and micro-grooving depth deviation has been considered as the output parameters for this present experiments for machining at different parametric combinations. This paper reports theoretical and experimental results of micro-grooved bio-ceramics with thicknesses of 3 mm by using pulsed DPSS laser. Taguchi based experimental design has been adopted to carry out experiments. Then Gray Relational Analysis (GRA) based multi response optimization of input process parameters for the outputs characteristics are performed to get the optimal conditions. The optimum machining parameters were found as; pulse frequency= 3 KHz, pulse width = 5% of duty cycle, diode current = 24 Amp and gas pressure=1.0 Kgf/cm2.Validity of the model has been checked through experiments and the error in upper width, lower width and micro-grooving depth deviation in the validation experiments are found to be satisfactory with minimal errors. Also Scanning Electron Microscopy (SEM) images after conformation test examined from cross-sections of the micro-grooved bio-ceramic samples.