Arshad Noor Siddiquee
Articles written in Sadhana
Volume 39 Issue 5 October 2014 pp 1035-1053
This paper investigates the effect of different cutting parameters (cutting speed, feed rate, and depth of cut) on surface integrity defined in terms of surface roughness and microhardness in dry hard turning process. The workpiece material used was hardened alloy steel AISI 52100 and it was machined on a CNC lathe with coated carbide tool under different settings of cutting parameters. Three cutting parameters each at three levels were considered in the study. Central composite design (CCD) of experiment was used to collect experimental data for surface roughness and microhardness. Statistical analysis of variance (ANOVA) was performed to determine significance of the cutting parameters. The results were analysed using an effective procedure of response surface methodology (RSM) to determine optimal values of cutting parameters. Several diagnostic tests were also performed to check the validity of assumptions. The results indicated that feed rate is the dominant factor affecting the surface roughness whereas the cutting speed is found to be the dominant factor affecting the microhardness. Results also revealed that within the range investigated, good surface integrity is achieved when feed rate and depth of cut are near their low levels and cutting speed is at high level. Finally, the optimal cutting parameters and model equations to predict the surface roughness and microhardness are proposed.
Volume 43 Issue 2 February 2018 Article ID 0026
The effects of flux composition on transfer of the elements have been studied through developed agglomerated fluxes on mild steel plates. The elements transferred to the welds have been shown in terms of a delta (Δ) quantity, which may be positive, negative or zero depending upon the composition of flux, wire and base plate. Carbon and manganese contents both show negative Δ quantity for most of the welds, indicating that both have been transferred from the weld metal to the slag. The results of this study show that for most of the welds, desulphurization and removal of phosphorus have been reported. The amount of element transferred is different for different welds depending upon the flux composition, dilution and slag metal reactions. Response surface methodology has been used for developing models for element transfer. The suggested model has been given for sulphur transfer to the weld. In this study the transfers of carbon, manganese, sulphur, phosphorus, silicon and nickel have been studied.