Sustainable Machining of Cf/SiC Ceramic Matrix Composite Using Green Cutting Fluids

Abstract

Understanding the machinability of carbon fiber reinforced silicon carbide (Cf/SiC) ceramic matrix composite is important due to its large number of applications in defense, aerospace, and automobile industries. Cf/SiC has unique properties like high hardness, low density, high strength to weight ratio, and high oxidative stability even at a higher temperature. However, machining of Cf/SiC is an arduous task owing to its anisotropic and non-homogeneous structure. In this work, sustainable machining of Cf/SiC composite is carried out using inhouse tailored vegetable-based green cutting fluid (GCF) and compared with “Synergy 735”, a petroleum-based commercial mineral oil (MO) with minimum quantity lubrication (MQL) technique. Surface integrity and surface roughness are measured against varying control variables such as cutting speed, depth of cut, and feed rate. After machining experiments, fiber pullout, fiber breakage, matrix cracking, and interfacial debonding of fiber-matrix are observed on the machined workpiece. Results show that GCF reduces up to 17% of surface roughness of machined workpiece over MO. Also, surface integrity is better for GCF compared to MO machined surfaces.