Investigations on the effect of silver nanoparticles on performance of coconut oil based cutting fluid in minimal fluid application

In this work, an innovative nanocutting fluid, based on coconut oil was developed by dispersing silver nanoparticles (AgNPs) of size less than 50 nm. The tribological and physical properties of the prepared nanocutting fluid with different volumes of silver nanoparticles were studied. It was found that the addition of 4% by volume of nanoparticles enhanced the properties of the nanocutting fluid compared to the other concentrations studied, thus demonstrating its excellent tribological performance. The effect of the newly developed nanocutting fluid with 4% of silver nanoparticles on cutting performance was also investigated while machining AISI4340 steel with minimal fluid application. Results revealed that the cutting force, cutting temperature, and tool wear are reduced on an average by 22.6%, 12.6%, and 5.3% respectively. It was evident that efficient cooling and lubrication of nanocutting fluid dispersed with silver nanoparticles improved the cutting performance. The outcomes of this work can be considered as a development toward eco-friendly and sustainable machining.

Graph Theory and Matrix Approach for Machinability Enhancement of Cryogenic Treated Cobalt Bonded Tungsten Carbide Inserts

Cryogenic treatment is a sustainable manufacturing process preferred to improve the properties of the material. In the present study, the effect of cryo treated tungsten carbide cobalt bonded insert (WC-Co) measured in terms of tool life and surface finish on dry turning on high strength AISI4340 steel at different machine parametric conditions. The observations of Untreated (UT) and Deep Cryo Treated (DCT) inserts were compared. Formation and the distribution of eta phase carbides are verified by Scanning Electron Micrograph (SEM). The DCT insert shows a reduction in 27.27% tool wear with an acceptable level of surface finish. Taguchi's coupled Graph Theory and Matrix Approach (TC-GTMA) is used to predict the optimum machining condition and to substantiate the results the validation experiment is conducted and found satisfactory.

Corrosion Failure of AISI4340 Steel in Oxygen-Containing Aqueous Chloride Solution

Stress corrosion cracking behavior of 4340 steel in oxygen-containing or chloride containing aqueous solution was researched, the tensile experiment results indicated 100°C deaerated distilled water, the rupture of 4340 steel mainly belongs to ductile fracture, the addition of oxygen or chloride would increase the SCC tendency of 4340 steel and transformed the rupture mechanism from ductile fracture to brittle rupture, the existence of oxygen or chloride would decreaseKISCCof 4340 steel in 100°C aqueous solution slightly, the simultaneous action of oxygen and chloride existed, and the simultaneous action would further increase the SCC tendency of 4340 steel in aqueous solution.