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Corrosion behavior of ZrC particles reinforcement with Al-12Si composites by weight loss method using acidic media

John C. F., Paul R. C., Singh S. C. E., Jacobjose J., Ramkumar T., Hikku G. S., Sharma R. K., Sengottuvel P.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2018

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Vol. 66, nr 1

9--16

EN

This paper aims to investigate the corrosion behavior of zirconium carbide (ZrC) reinforced Al – Si metal matrix composites (MMCs) in a mixture of acidic solution using weight loss method. The composites are prepared by powder metallurgy method. Al-12Si-xZrC composites containing 0, 5, and 10 weight percentage of ZrC particles are compacted in a die set assembly and sintered in an inert gas muffle furnace. The acidic solutions used for corrosion are 1 N HCl, 1 N H2SO4 and 1 N HNO3. The corrosion characteristics of Al-12Si-xZrC composites and the pure Al were experimentally evaluated. The corrosion test was carried out at different weight proportions of the samples in various concentrations of the acid such as 1 N HCl, 1 N H2SO4 and 1 N HNO3 for different exposure time (i.e., 24 h, 72 h, 144 h and 216 h), respectively. The results specified that corrosion rate of composites was lower than that of base metal Al under the corrosive atmosphere, regardless of exposure time and acidic solutions used as corrodents. Al-12Si-xZrC composites become more corrosion resistant as the ZrC content is increased. This is because of the development of stable oxide layer above the specimens. Scanning electron microscopy (SEM) confirms the degree of attack of acidic solution on the surface of the examined material.

2

Tribological behavior, mechanical properties and microstructure of Al-12Si-ZrC composite prepared by powder metallurgy

John C. F., Paul R. C., Singh S. C. E., Ramkumar T.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2017

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Vol. 65, nr 2

149--154

EN

High-energy mechanical alloying method was used to prepare Al-12Si-xZrC (x = 0, 5, 10, 15 wt. %) nanocomposites. Cylindrical preforms were prepared with an initial preform density of 89% by using a suitable die and punch assembly. The preforms were sintered in a muffle furnace with an inert gas atmosphere at a temperature of 550°C, followed by cooling until room temperature has been attained. Scanning electron microscope (SEM) and X-ray diffraction (XRD) techniques were used to characterize the composites. Pin-on-disc wear testing machine was used to determine the tribological properties of the prepared composites. The results show that the wear loss reduced with increasing the reinforcement content and coefficient of friction increases gradually.

3

Artificial neural network based tool wear estimation on dry hard turning processes of AISI4140 steel using coated carbide tool

Rajeev D., Dinakaran D., Singh S. C. E.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2017

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Vol. 65, nr 4

553--559

EN

Nowadays, finishing operation in hardened steel parts which have wide industrial applications is done by hard turning. Cubic boron nitride (CBN) inserts, which are expensive, are used for hard turning. The cheaper coated carbide tool is seen as a substitute for CBN inserts in the hardness range (45–55 HRC). However, tool wear in a coated carbide tool during hard turning is a significant factor that influences the tolerance of machined surface. An online tool wear estimation system is essential for maintaining the surface quality and minimizing the manufacturing cost. In this investigation, the cutting tool wear estimation using artificial neural network (ANN) is proposed. AISI4140 steel hardened to 47 HRC is used as a work piece and a coated carbide tool is the cutting tool. Experimentation is based on full factorial design (FFD) as per design of experiments. The variations in cutting forces and vibrations are measured during the experimentation. Based on the process parameters and measured parameters an ANN-based tool wear estimator is developed. The wear outputs from the ANN model are then tested. It was observed that as the model using ANN provided quite satisfactory results, and that it can be used for online tool wear estimation.

4

Effect of milled B4C nanoparticles on tribological analysis, microstructure and mechanical properties of Cu–4Cr matrix produced by hot extrusion

Singh S. C. E., Selvakumar N.

Archives of Civil and Mechanical Engineering

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2017

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Vol. 17, no. 2

446--456

EN

In this paper, the dry sliding wear and friction behavior of Cu-4Cr-xB4C nanocomposites produced by powder metallurgy by varying the proportions of boron carbide viz. (x = 0, 4 and 8 wt.%) were studied. Die set assembly was preferred for making green compacts using a compression testing machine. The sintered compacts were hot extruded at 600 °C to reduce the porosity and to attain preform density of 92%, thereby improving the hardness and wear resistance. Scanning electron microscope (SEM) and X-ray diffraction were used to characterize the powders. Vickers hardness tester was used to evaluate the hardness of different compositions. Pin-on-disc instrument was used to find out the wear behavior of the composites. It was found that the wear loss and friction coefficient increased with an increase in applied load and sliding distance for all the compositions. The wear mechanisms which could be interpreted with SEM analysis of the nanocomposites were also studied.

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Influence of nano ZrC content on tribological analysis, microstructure and mechanical properties of Cu–4Cr matrix composites produced by hot extrusion

Selvakumar N., Singh S. C. E.

Archives of Civil and Mechanical Engineering

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2016

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Vol. 16, no. 3

537--552

EN

In the present study, Cu–4Cr–xZrC nanocomposites have been developed through powder metallurgy route by varying the proportions of zirconium carbide viz. (0–10 wt.%). The required green compacts were prepared using die set assembly in a compression testing machine. Consequently, the hot extruded samples were tested for dry sliding wear and friction using a pin-on-disc machine. SEM, XRD, pin on-disc system and Vickers hardness tester were used to evaluate the characterization, tribological properties and hardness respectively of Cu–4Cr–xZrC nanocomposites. From the observations, it was found that the friction coefficient increased progressively with increasing load and sliding distance. Furthermore, the specific wear rate (SWR) decreased for the Cu–4Cr–xZrC nanocomposites when compared to composites that of pure copper. Hardness increases with the addition of nano ZrC content into the matrix composites.