The drilling is well known as one of the most common hole making processes in the industry.Due to close tolerance requirement for drilled holes in the most of work pieces, onlinecontrolling of the diameter of drilled holes seems to be necessary. In the current work, an onlinedimensional controlling system was developed for drilling process. Doing this, drilling processwas executed in different cutting conditions (feed per tooth and cutting speed) and different flankwear of cutting edges. In each drilling test, axial force and diameter of drilled hole was recorded.According to the results obtained from analysis of variance (ANOVA), increase of flank wear incutting edges increases the axial force and hole-diameter. In this way, the axial cutting force, asonline measurable parameter, could be used for online estimation of the hole-diameter. Neuralnetwork (NN) was used to model the correlation between axial force and the hole-diameter. Inthis way, the obtained NN model estimates the maximum acceptable axial force by receivingcutting conditions and maximum acceptable hole-diameter. The drilling process has to bestopped as its axial force exceeds the estimated value for drill changing. Manuscript profile

Nowadays, polymer-based Nano-composites are of special importance in industry considering their mechanical properties including high strength to weight ratio. On another hand, since Nano-composites produced by methods such as extrusion are at simple cross sections, it is necessary to machine them in order to reach geometrically complex figures. Surface roughness is a parameter affecting mechanical specifications of the machined part. Thus, it is necessary to study surface roughness of the machined parts to reach optimized cutting parameters and optimized surface roughness. The present paper tries to experimentally test milling of Nylon 6/ CaCo3 Nano-composites and measure surface roughness of the milled surfaces using the obtained data. The obtained data were used to model surface roughness to obtain an appropriate model for its milling. Finally, the obtained model was optimized using harmony search algorithm to reach optimized surface roughness and cutting parameters. Manuscript profile