Optimization using genetic algorithm of tribological behaviour of WC tool material

In this investigation we have used a heuristic approach to optimize the process parameters in terms of tool wear rate. We have used the L8 orthogonal array design of experiments with three input parameters set at two levels. We have carried out the experimentation on two different processes viz. dry sliding and dry turning processes. An attempt has been made to achieve and validate the results obtained from these processes to check the repeatability of values in the same experimental environment. The tool material chosen for tool insert is Tungsten Carbide which is used in the manufacturing industries. We have optimised the results obtained on tribometer under the dry sliding process through a modern optimization technique i.e. genetic algorithm. The response surface methodology model (L8 orthogonal array) formed the basis for the development of genetic algorithm model through which we have defined the conditions. We have used the conditions of minimum tool wear for turning process, minimum coefficient of friction and minimum surface roughness for sliding process on a pin-on-disc test rig. It has been inferred that the sliding and turning processes under the conditions of no lubrication yielded analogous results. We have verified the same results practically by performing confirmation experiments on lathe machine for turning operation under the same experimental conditions

Optimization using genetic algorithm of tribological behaviour of WC tool material

889-896In this investigation we have used a heuristic approach to optimize the process parameters in terms of tool wear rate. We have used the L8 orthogonal array design of experiments with three input parameters set at two levels. We have carried out the experimentation on two different processes viz. dry sliding and dry turning processes. An attempt has been made to achieve and validate the results obtained from these processes to check the repeatability of values in the same experimental environment. The tool material chosen for tool insert is Tungsten Carbide which is used in the manufacturing industries. We have optimised the results obtained on tribometer under the dry sliding process through a modern optimization technique i.e. genetic algorithm. The response surface methodology model (L8 orthogonal array) formed the basis for the development of genetic algorithm model through which we have defined the conditions. We have used the conditions of minimum tool wear for turning process, minimum coefficient of friction and minimum surface roughness for sliding process on a pin-on-disc test rig. It has been inferred that the sliding and turning processes under the conditions of no lubrication yielded analogous results. We have verified the same results practically by performing confirmation experiments on lathe machine for turning operation under the same experimental conditions

Characterization and Parametric Optimization of Performance Parameters of DLC-Coated Tungsten Carbide (WC) Tool Using TOPSIS

In this work, we have deposited the diamond-like carbon (DLC) coating on the tungsten carbide (WC) tool insert using the thermal chemical vapor deposition (CVD) method. For the growth of DLC coating, sugarcane bagasse was used as a carbon precursor. Raman spectroscopy, a field emission scanning electron microscope (FESEM), and X-ray diffraction (XRD) were used to confirm the presence of DLC coating on the tungsten carbide tool inserts. The hardness tests were also performed for inspecting the microhardness induced by the self-developed DLC coating on the tungsten carbide (WC) tool insert. To determine the optimum process parameters for the turning operation on an aluminum (6061) workpiece using a self-developed DLC-coated tungsten carbide (WC) tool insert, we have applied the technique for order preference by similarity to ideal solution (TOPSIS) methods. The process parameters considered for the optimization were feed rate, cutting speed, and depth of cut. Whereas chosen response variables were flank wear, temperature in the cutting zone, and surface roughness. TOPSIS is utilized to analyze the effects of selected input parameters on the selected output parameters. This study in this paper revealed that it was advantageous to develop the DLC coating on the tungsten carbide tool inserts for the machining applications. The results also revealed that a 0.635 mm depth of cut, feed rate of 0.2 mm/rev, and cutting speed of 480 m/min were the optimum combination of process parameters

Primary adrenal teratoma: An unusual tumor – Challenges in diagnosis and surgical management

We report a rare case of a 25-year-old lady who presented with right hypochondriac pain associated with weakness for 3 months. Her hormonal evaluation was normal. Computed tomography scan revealed an adrenal mass for which a right open transperitoneal adrenalectomy was performed, and the lesion was diagnosed as mature teratoma on histopathological examination. Teratoma is an unusual neoplasm which arises from one or all the three germ layers. Extragonadal teratomas are rare in adults as compared to children and are mostly retroperitoneal in location, constituting only 4% of all primary teratomas. Primary adrenal teratomas are even rarer and to the best of our knowledge, only eight cases have been reported in adults in the past 10 years. Adrenal teratoma can pose a diagnostic challenge because radiologically it mimics myelolipoma, angiomyolipoma, liposarcoma, or pheochromocytoma. Mature teratomas are usually benign but may possess malignant potential, the chances of which are greater in adults as compared to children, making it an important entity requiring a proper diagnosis and management

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