Informatics Publishing Limited

P. Nanda Kumar ¹, G. Ranga Janardhana ²

Affiliations
1 Sri Vekateswara College of Engg & Technology, RVS Nagar, Tirupati Rd., Chittoor, AP, IN
2 Dept. of Mech. Engg., Jawaharlal Nehru Technological University, Kakinada, IN

Abstract

Surface roughness plays on important role in manufacturing and the product quality depends on the surface roughness. The present work focuses on developing a multiple regression model with intercepts for the prediction of surface roughness of Titanium alloys machined on CNC milling machine. The working parameters, viz. speed, feed and depth of cut and surface roughness as response are considered in this model. The experiments were conducted based on factorial design using Design of Experiments (DOE). The prediction models are developed using Multiple regression techniques with and with out interaction terms of both Linear and Non Linear. The values of surface roughness predicted by this model are then verified with additional experimental results. Experimental results and regression analysis demonstrate that the model developed in this work predicts the surface roughness values with good accuracy.

Keywords

Surface Roughness, Titanium Alloy, Design of Experiments, Linear and Exponential Regression Analysis, Percentage Deviation.

Full Text

     

B. Satyanarayana ¹, G. Ranga Janardhana ², D. Hanumantha Rao ³

Affiliations
1 Dept. of Mechanical Engg., VNR Vignana Jyothi Institute of Engg. & Technology, Hyderabad, IN
2 College of Engg., JNTU, Vizayanagaram, IN
3 Dept. of Mechanical Engg., MVSR Engineering College, Hyderabad, IN

Abstract

Inconel 718 is one of the most difficult-to-cut materials because of its low thermal diffusive property, high hardness, and high strength at high temperature. This paper presents a hybrid optimization approach for determination of the optimum turning process parameters (speed, feed and depth of cut) which minimize the Surface Roughness (SR) and maximize Metal Removal Rate (MRR) together in CNC high speed turning of Inconel 718 nickel based super alloy with uncoated tungsten carbide cutting tool. A multi-response optimization has been carried out by using Taguchi method based Grey Relational Analysis (GRA). Also the significant process parameters have been found out for the above process optimization by performing an ANOVA. Confirmation tests with the optimal levels of cutting parameters are carried out in order to illustrate the effectiveness of the method. Validations of the modeled equations are proved to be well within the agreement with the experimental data.

Keywords

Inconel 718, Multi-Response Optimization, Grey Relational Analysis, Taguchi Method, ANOVA.

Full Text

     

K. Srinivasulu Reddy ¹, G. Ranga Janardhana ², Kim S. Kun ³

Affiliations
1 JNT University, Hyderabad, IN
2 Hoseo University, Asan City, KR
3 Dept. of Automobile Engg., Hoseo University, Asan City, KR

Abstract

The effects of modification and vibration during solidification of Aluminum-Silicon eutectic alloy (LM6) are studied and compared with unmodified alloy. Sodium and Strontium are used as modifiers. Horizontal sinusoidal vibration at different frequencies was imposed using a vibration table. It was found that modification treatment improves properties such as ultimate tensile strength (UTS), percentage elongation, hardness, toughness, cutting force, electrical conductivity, thermal conductivity and optimum values were obtained at 1.5% by weight addition of modifier. Vibration imposed during solidification on the modified alloy further improved the properties at 15 Hz frequency of vibration. Neuro fuzzy model was developed to predict the properties at different percentages of modifiers and different frequencies of vibration. From the studies of sensitivity analysis, it was found that UTS is more sensitive to % modifier and thermal conductivity is more sensitive to frequency of vibration. Similar models were also developed to predict porosity and fatigue strength. The developed models are validated experimentally.

Full Text

     

M. Bala Chennaiah ¹, P. Nanda Kumar ², G. Ranga Janardhana ³, N. Mohan Rao ³, D. Hema ⁴

Affiliations
1 Mech. Engg., Dept., V R Siddhartha Engineering College, Vijayawada, IN
2 Narayanadri Institute of Science and Technology, Rajampet, Kadapa, IN
3 JNTU, College of Engg., Kakinada, IN
4 Sree Potti Sriramulu Chalavadi Mallikarjun Rao College of Engg. & Technology, Vijayawada, IN

Abstract

Finite Element Analysis (FEA) has become a practical method of predicting stresses and deflection for loaded structures. EEA accurately identifies the load path, which can he difficult using Classical Analysis with complex structures. EEA shell element models are effective for predicting loads in weldments fabricated from plate, sheets, structural shapes and tube. The formulation used for a finite element shell model is that of full penetration welds at every joint. Here a method to derive the loads at weld joint from stress results of FEA shell element model is presented. Apart from these loads, twisting moments is also introduced and twisting load is calculated. Hence the total effect of all these loads is considered. The weld loads, weld throat size requirements are calculated using classical methods. The FEA arid Classical method results are compared and the importance of FEA is justified.

Keywords

Weld Load, Weld Throat, Finite Element Analysis, Shell Element Model, Classical Analysis.

Full Text