Turn milling is one of the machining processes used to mill circular work pieces while the work piece rotates about its own axis. Orthogonal milling is one of the turn milling processes where the bottom part of cutter removes material from the rotating work piece with high metal removal rate. In this article, tool condition was studied by analyzing surface roughness and vibration of cutter with the use of response surface methodology. According to design of experiments, 16 experiments were conducted on ASTM B139 phosphor bronze with high-speed steel end mill cutter on four-axis milling machine. The response surface methodology was used to find out significant parameters that are affecting surface roughness and amplitude of cutter vibration. A multi-response optimization technique was used to identify optimum cutting parameters for less surface roughness and amplitude of cutter vibration.

Wire electric discharge machining is an efficient technique among the available nonconventional machining process and is mostly used for machining complex shapes and hard materials. This process also acts as a form of surface modification technique. The discharge energy of machining process influences the nature of the machined surface to a very high degree due to high heat generation and deposition of wire electrode material. 316L stainless steel is widely used in engineering, marine and medical applications. Although 316L SS is a corrosion resistant material, there is a lot of research going on to improve its corrosion resistance by different surface modification techniques due to its applications. Investigation on the effect of WEDM parameters on the corrosion behavior of 316L SS material is carried out. Corrosion studies were carried out by Potentiodynamic polarization test and phase analysis was carried out by using XRD. Significant enhancement in the corrosion resistance of WEDMed surface is observed with the variation in pulse on time and peak current. Pulse on time and peak current are the significant parameters influencing the amount of discharge energy. Low level of discharge energy enhanced the corrosion resistance of WEDMed surface.

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This paper presents a combined finite element and model Lamb waves propagation parameters method as a tool for structural health monitoring in composite materials. Modal analysis allows identifying the mode conversions induced by the defects. A simulation combining a lossless finite element approach and Lamb wave propagation parameter for finding natural frequencies and mode shapes of the structures in undamaged and damaged condition is proposed. This analysis is performed on two carbon-fiber-reinforced plastic bars in both undamaged and damaged state, where the two damaged states are (1) having a cut partway through the bar, perpendicular to the long axis of the bar and (2) having a circular hole. The lamb wave propagation parameters are calibrated using the ultrasonic pulse generator test setup. The natural frequencies for the theoretical, finite element and experimental results are compared and close agreement is found between the frequencies obtained experimentally and computationally.

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