Optimizing cutting parameters in hard turning of AISI 52100 steel using TOPSIS approach

In the present work optimization of cutting parameters is performed while hard turning of AISI 52100 steel with polycrystalline cubic boron nitride (PCBN) tools using Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). Experiments are planned and conducted based on Center Composite Rotatable Design (CCD) of the Response Surface Method (RSM). Cutting speed, feed, depth of cut, nose radius and negative rake angle are considered as input parameters. In this study machining force (F) and surface roughness (Ra) are measured during the experiment. Analysis of variance (ANOVA) is deployed to determine the influence of process parameters. Obtained optimal parameters are speed 200 rpm, feed 0.1 mm/rev, depth of cut 0.8 mm, nose radius 1.2 mm and negative rake angle 45º

COMPARATIVE STUDIES ON DURABILITY AND MECHANICAL PROPERTIES OF M50 GRADE STEEL FIBRE REINFORCED CONVENTIONAL AND SELF-COMPACTING CONCRETES

Durability of concrete structures has been a topic of research for a long time. Many modifications and various attempts are being made by Engineers and scientists have been proposed in convectional concrete in order to improve its overall performance, including strength and durability. An attempt has been made to study the comparison between M50 grade SCC and CVC with steel fibers dosage of 30 Kg/m³, 60 Kg/m³, and 90 Kg/m³ with aspect ratio of 35 and subjected to durability and mechanical strengths. In this experimental work, the scc concrete was designed using different available methods. From those, by trial and error, quantities for mix were obtained with satisfied properties of SCC. Trials have been made based on NAN SU method and finally arrived at the quantities, which satisfied the properties of SCC i.e., slump flow test, L-Box test, U-Box test and V-Funnel test. To this mix, steel fibers of different aspect ratios and varied quantities of 30, 60 and 75kg/m3 were added.The following parameters were studied under the durability aspect viz., weight loss, strength and consumption of solutions. The durability studies were carried out by conducting the tests viz., Water Absorption, Marine Water Attack, Magnesium Sulphate Attack, Sodium Sulphate Attack and Hydrochloric Acid