INFLUENCE OF WIRE-EDM PARAMETERS ON SURFACE CHARACTERISTICS OF SUPERALLOY MONEL 400

Progressive development in the industrial field leads to the increasing demand for superalloys with enhanced mechanical properties, such as toughness, hardness, ductility, damping strength, tensile strength and improved surface finish. Monel 400, one of such superalloys, with the majority of its application in aerospace and marine fields demands a good super finish. There arises the need for some nonconventional processes like WEDM. This process is more effective to obtain complex shapes to close tolerance. This research focuses on clear understanding of the machining strategies with proper parametric combinations to achieve an improved surface finish, subsequently reducing the time and expense involved in the superfinishing procedure. The surface qualities of the selected samples are validated with the help of roughness profile and topography images. This study has proven that the increasing input current and wire feed rate (WFR) consistently decreases the surface roughness (SR; [Formula: see text] of the specimen. This paper also explains the effect of topographic parameters and microstructure over the resulting SR. In addition, the consistent contribution of WFR and input current toward the lower SR is established. The relationship between morphological behavior and parametric deviations is evaluated. A significant correlation found to exist between the rate of wire feed and the height parameters of SR such as [Formula: see text], [Formula: see text], etc.

Performance assessment of energy efficient and eco-friendly turning of Nimonic C-263: A comparative study on MQL and cryogenic machining

Nimonic C-263 is predominantly used in the manufacturing of heat susceptible intricate components in the gas turbine, aircraft, and automotive industries. Owing to its high strength, poor thermal conductivity, the superalloy is difficult to machine and causes rapid tool wear during conventional machining mode. Moreover, the unpleasant machining noise produced during machining severely disrupts the tool engineer’s concentration, thereby denying a precise and environment friendly machining operation. Hence, close dimensional accuracy, superior machined surface quality along with production economy, and pleasant work environment for the tool engineers is the need of an hour of the current manufacturing industry. To counter such issues, the present work attempts to compare and explore the machinability of two of the most popular machining strategies like minimum quantity lubrication (MQL) and cryogenic machining process during turning of Nimonic C-263 work piece in order to achieve an ideal machining environment. The machining characteristics are compared in terms of surface roughness (SR), power consumption (P), machining noise (S), nose wear (NW), and cutting forces (CF) to evaluate the impact of machining variables like cutting speed (Vc), feed (f), and depth of cut (ap) with a detailed parametric study and technical justification. Yet again, an investigation is conducted to compare both the machining strategies in terms of qualitative responses like chip morphology, total machining cost, and carbon emissions. The study revealed that cryogenic machining strategy is adequately proficient over MQL machining to deliver energy proficient and gratifying work environment for the tool engineers by reducing the cost of machining and improving their work efficiency.

Review on Experimental and Theoretical Investigations of Ultra-Short Pulsed Laser Ablation of Metals with Burst Pulses

Laser processing with ultra-short double pulses has gained attraction since the beginning of the 2000s. In the last decade, pulse bursts consisting of multiple pulses with a delay of several 10 ns and less found their way into the area of micromachining of metals, opening up completely new process regimes and allowing an increase in the structuring rates and surface quality of machined samples. Several physical effects such as shielding or re-deposition of material have led to a new understanding of the related machining strategies and processing regimes. Results of both experimental and numerical investigations are placed into context for different time scales during laser processing. This review is dedicated to the fundamental physical phenomena taking place during burst processing and their respective effects on machining results of metals in the ultra-short pulse regime for delays ranging from several 100 fs to several microseconds. Furthermore, technical applications based on these effects are reviewed.

ROLE OF SUSTAINABLE TECHNIQUES IN MANUFACTURING PROCESS: A REVIEW

Customary mineral based liquids are as a rule broadly utilized in cooling and greases in machining activities. Nonetheless, these cutting liquids are the suitable wellspring of numerous natural and organic issues. To kill the evil impacts related with cutting liquids, it is important to move towards practical machining methods. Such sustainable machining techniques utilize minimize the amount of cutting liquid, fluid nitrogen, vegetable oil or packed air as a cooling-oil medium. The liquids utilized in economical machining strategies are viewed as absolutely biodegradable and Eco-friendly. This paper is a careful survey of the relative multitude of current environmental friendly machining methods as of now rehearsed in the metal cutting cycle. It has been likewise discovered that these economical machining strategies more often than not give better outcomes as far as improved surface nature of the machined part, upgraded apparatus life, less cutting temperatures and slicing powers when contrasted with traditional wet machining techniques. The principle motivation behind this survey work is to recognize the diverse supportable strategies and empower the utilization of such procedures in metal machining, so that, the reducing interaction turns out to be more expense powerful and climate inviting.

A Review on the Abrasive Water-Jet Machining of Metal–Carbon Fiber Hybrid Materials

The bonding of metallic alloys and composite materials in the form of a hybrid structure is a line of great interest for the current industry. The different machinability of both materials requires a specific machining process. Abrasive water-jet machining (AWJM) is an excellent technology for the simultaneous machining of both materials. However, defects at the micro and macro-geometric level have been detected in several scientific articles. In this review, a detailed study of the two main defects in metals, composite materials and hybrid structures has been developed. The conclusions of several scientific articles have been exposed for a better understanding of the topic in articles between 1984 and 2020. The influence of the cutting parameters on the reduction in kinetic energy of the water jet and the order of stacking of the materials in the hybrid structure is the main objective in order to minimize these defects. Cutting parameter optimization studies, predictive model proposals, process-associated defects and evaluation methodologies have been discussed. The aim of this article is to set a solid background on AWJM machining in hybrid structures and on the influence of cutting parameters on generated defects and machining strategies to obtain the best results at a macro and micro-geometric level.

Investigations on the surface quality of grinded inner contours using different manufacturing strategies on fused silica

In the field of optical manufacturing, fused silica has a high and constantly growing application potential. Its material advantages, such as low thermal expansion and high thermal shock resistance, as well as its high transparency from the ultraviolet to the infrared spectral range, result in a large number of application fields. For example, manufacturing processes in semiconductor technology require high-quality quartz materials throughout the wafer handling process to avoid non-permissible contamination and to withstand the high process temperatures. Another example are monolithic components for fiber preform manufacturing, where internal contours with high aspect ratios (e.g. component length to component diameter) and high surface qualities are required to draw fiber types with special properties. The demands on the complexity and accuracy of these components are constantly increasing, which is accompanied by the need to analyse and optimize modern CNC manufacturing techniques more and more. In the following, investigations on the grinding of internal contours with a high aspect ratio are presented, in which the influence of an ultrasonic assistance as well as different machining strategies are considered.