Audhesh Narayan

Thermal finite element analysis of high efficiency deep surface grinding

The study of grinding contact zone temperature and temperature distribution in the workpiece during high efficiency deep surface grinding (HEDSG) is important for the quality of the product and wheel wear. As a consequence of the high temperatures present in HEDSG, not only wheel wear increases, but large residual stresses may also develop in the workpiece resulting in surface cracks. Even microstructural changes occur if the temperature is sufficiently large. The present work aims to develop a two-dimensional (2D) thermal finite element method (FEM) model for the simulation of temperature in the contact zone as well as in the whole workpiece during HEDSG. The present model has been used for the calculation of temperature distribution in the workpiece during a deep grinding scenario and the results compared with the available results in literature. The effect of temperature dependent thermal properties and heat flux profile on temperature distribution in the workpiece has also been investigated. Parametri...

Investigation of Temperature Distribution in the Workpiece during Creep Feed Surface Grinding Using Finite Element Method

High energy input of grinding that is dissipated as heat in grinding zone leads to thermal damage to the workpiece material. Heat transfer phenomena during deep cut grinding in general and creep feed deep cut grinding in particular is entirely different than the shallow cut grinding processes. Therefore, investigation of the temperature distribution becomes important in such situations. In the present work, a two dimensional thermal-based finite element model has been developed to investigate the transient temperature distribution within the contact zone as well as in the whole workpiece due to creep feed surface grinding. After comparing the results of the present model with the available results, the model is used for the study of effect of different input parameters such as depth of cut, workpiece speed, heat flux profile, and wheel material on transient temperature distribution.

Thermal stress distribution in the workpiece during creep-feed surface grinding

High amount of energy generated during creep-feed surface grinding is dissipated as heat in grinding zone. Due to high and uneven temperature, thermal stresses are generated in the workpiece. Thermal stresses can lead to micro-cracks, decrease in strength and fatigue life of the components. Therefore, investigation of the thermal stress distribution in the workpiece becomes important in such situations. In the present work, thermal stresses have been predicted using temperature as input. A two-dimensional finite element-based temperature and thermal stress model has been developed to investigate the thermal stress distribution within the workpiece due to creep-feed surface grinding. After comparing the results of present model with the available results, the model is used to study the effect of different input parameters such as depth of cut, workpiece speed, wheel speed and wheel material on thermal stress distribution.

Modelling and multi-response optimisation of sinking micro-electrical discharge machining of AISI 4140 steel

Improving productivity and surface quality in sinking micro-electrical discharge machining (S-MEDM) process is still a challenging task for manufacturing engineers. In order to fulfil these requirements, modelling and optimisation of the S-MEDM process is needed. In this paper, a prediction model for S-MEDM process has been developed using the coupled methodology of finite element method (FEM) and artificial neural network (ANN). First, a FEM-based model is developed incorporating realistic aspects such as Gaussian heat flux distribution, time dependent spark radius, temperature dependent workpiece material properties and phase change phenomenon. Further, an ANN model is developed utilising the data generated by FEM-based model for training and testing of the network. The trained ANN model has been used for the prediction of the material removal rate and surface roughness (Ra). Weighted principal component (WPC) method is effectively employed for multi-response optimisation of S-MEDM process using prediction data of ANN model. The optimum setting of process parameters gives an improvement of 22.68% in material removal rate and a decrease of 17.30% in surface roughness.

Investigation of Temperature Distribution in the Workpiece During High Speed Deep Surface Grinding using FEM

High amount of energy generated in the grinding zone is dissipated as a heat which leads to thermal damage to the workpiece. Heat transfer phenomena in high speed deep surface grinding (HSDSG) is entirely different than conventional shallow cut grinding. Due to high wheel speed and large depth of cut, the temperature rise in the grinding zone becomes very high during high speed deep surface grinding. Therefore, investigation of the temperature distribution becomes important in such situations. In this paper, a two dimensional thermal based finite element model has been developed to investigate the transient temperature distribution within the contact zone as well as in the whole workpiece due to high speed deep surface grinding. After comparing the results of present model with the available results, the model is used to study the effect of different input parameters such as depth of cut, workpiece speed, heat flux profile and wheel material on transient temperature distribution.