Rotary ultrasonic milling of C/SiC composites fabricated using chemical vapor infiltration and needling technique

Carbon fiber reinforced silicon carbide (C/SiC) has a widespread application in the aerospace industry owing to its superior properties like hardness, wear resistance, low density and heat resistant. However, poor characteristics of conventional machining of C/SiC composite has impoverished its utility in space and military applications. To overcome this problem, a new method of rotary ultrasonic milling has been used for machining the composites with a varying material density which have been prepared using chemical vapor infiltration (CVI) and needling technique available at Indian space research organization. Different response characteristics were studied with different machining parameters namely material density, feed rate, and axial depth of cut. The pragmatic results revealed that maximum average change in the surface roughness is 6.08 mu m for 1.74 g cm(-3), 50 mm min(-1), and 0.01 mm whereas material removal rate decreases by 33.29%, 66.57%, and 66.82% on increasing the material density from 1.74 to 2.46 g cm(-3), feed rate from 50 to 200 mm min(-1), and axial depth of cut from 0.01 to 0.04 mm respectively. Furthermore, it is apparent from tool wear study that wear reduces as the material density is decreased. Subsequently, morphological examination revealed that SiC was uniformly distributed throughout the sample and very less gap present inside the structure and energy dispersive spectroscopy confirms the presence of carbon (45.77%) and silicon (54.23%) in the fabricated composites.