Study on the weldability, microstructure and mechanical properties of thick Inconel 617 plate using narrow gap laser welding method

In the current scenario, biocompatible or biomedical materials are rising in demand for specific application requirements and its machining is one of the fundamental challenges. Many researchers fo...

Critical review on the impact of EDM process on biomedical materials

In this study the influence of TiC content on the mechanical and electrical properties of Al2O3-TiC composites containing 30 and 40 vol.% TiC were investigated. The Vickers hardness and fracture toughness of the composites increased with the addition of TiC phase. The composite with 40 vol.% TiC showed the highest flexural strength (687 ± 39 MPa), fracture toughness (7.8 ± 0.4 MPa·m1/2) and hardness (22.3 ± 0.3 GPa) with a homogeneous distribution of the second phase within the ceramic matrix. Besides enhanced mechanical properties, it was found that ceramic composites with more than 30 vol.% TiC fabricated by the spark plasma sintering possess sufficient electrical conductivity for electrical discharge machining as well. Therefore, they do not limit the flexibility of the shape, and any intricate parts can be easily made with these composites which can be recommended for the production of cutting inserts in the tools for machining of superhard hardened steels, hard-to-machine materials, composites and other materials used in mechanical engineering.

The Effect of TiC Additive on Mechanical and Electrical Properties of Al2O3 Ceramic

Tribological investigations of wear resistant layers developed through EDA and WEDA techniques on Ti6Al4V surfaces: Part I – Ambient temperature

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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Corrosion behavior of surface induced by wire EDM on 316L stainless steel: an experimental investigation

Titanium (Ti) alloy, Ti–6Al–4V (commonly known as Ti64), is employed in numerous applications due to their superior strength to weight ratio, low cost to performance ratio, tensile strength, and corrosion resistance properties. However, due to its poor tribological (friction and wear) properties and difficult-to-machine material, its implementation in the intended applications is limited. Nevertheless, Ti64 can be accurately machined using wire electrical discharge machining (WEDM) and further, this process develops a recast layer on the surface of Ti64, which posses larger percentage of oxygen. Therefore, in the present work, it is hypothesized that, the presence of the recast layer on the surface of Ti64 may enhance its tribological properties. To validate the proposed hypothesis, pins of (1) pure Ti64 and (2) WEDMed Ti64 were slided against EN32 steel disc on a pin on disc experimental setup for load of 50 N, rotational speed of 200 rpm and sliding distance of 500 m. In-situ analysis (scanning electron microscope and energy dispersive spectroscopy) and mechanical properties (nano-hardness and elastic modulus) were performed on the pin’s surface, to identify the change in properties. Obtained results indicated significant increase in the oxide layer formation, consequently enhanced the tribological properties of WEDMed Ti64 compared to pure Ti64. To understand the tribological behavior of WEDMed Ti64 at other rotational speed and load, second set of experiments was performed by varying load (50, 70 and 90 N) and rotational speed of (200, 400 and 600 rpm). It was observed that wear values were not proportional to increase in load and speed. To identify the condition favoring the tribological behavior, multi-response optimization technique was performed and the identified load and speed values for the optimum tribological behavior were estimated.

Multi Response Optimization and Experimental Investigations into the Impact of Wire EDM on the Tribological Properties of Ti–6Al–4V

Nickel based superalloy (alloy 617) exhibits high strength and oxidation resistance at elevated temperatures. The major limitation of this alloy is microsegregation of alloying elements due to the formation of Molybdenum (Mo) rich secondary phases in the interdendritic region of the weldments. The present study investigates the possibilities to mitigate the microsegregation effect. In order to achieve this, weld joints were fabricated with pulsed current gas tungsten arc welding (PCGTAW) techniques with three different filler wires. The filler wires employed with present study are ERNiCrMo-4, ERNiCrMo-10 and ERNiCrMo-14. The macro examination was carried out to reveal the defects in the weld joints. Optical and Scanning electron microscope (SEM) analysis were performed to evaluate the micro structural changes in the fusion zone and Heat Affected Zone (HAZ). Microstructure shows the fine equiaxed dendrite structure in the fusion zone. Energy Dispersive x-ray Spectroscopy (EDS) analysis was also carried out in the weldments to quantify the level of microsegregation of alloying elements. Tensile test reveals the strength and ductility of the weld joints. Root and face bend test was carried out to check the ability of the weld joints to withstand bending forces. The result shows the defect free weld was achieved in all the welded joints. EDS analysis revealed the presence of Mo rich phases in the ERNiCrMo-4 filler wire. There is no evidence for the formation of secondary phases in the filler wires. The tensile strength of ERNiCrMo-14 filler shows the marginally higher strength compare to other filler wires. Root and Face bend test did not show the presence of cracks and other defects in the weldments.

https://iopscience.iop.org/article/10.1088/2053-1591/aacb56/pdf

P. Kuppan

Papers

Multi Response Optimization and Experimental Investigations into the Impact of Wire EDM on the Tribological Properties of Ti–6Al–4V

Characterization of microstructure and mechanical properties of nickel based superalloy 617 by pulsed current gas tungsten arc welding technique

Experimental Investigations on Magnetic Field Assisted Abrasive Finishing of SS 316L

Studies on the effect of filler wires on micro level segregation of alloying elements in the alloy 617 weld fusion zone

Investigation on microstructure and mechanical properties on pulsed current gas tungsten arc welded super alloy 617