The Al 6061 was recycled by using the powder metallurgy technique to determine the effect of particle size distribution on mechanical and microstructure of materials. Analysis of the microstructure, green density and microhardness was conducted to test the performance of recycled aluminium. The project was conducted by using Al 6061 with the addition of 4% of alumina (3-4 μm). The results showed that green density of Al 6061 was lower than pure Al 6061. As the speed of ball mill increases from 100, 150 and 200 rev min −1 , the green density increases. Next, the samples were sintered at 500, 550 and 600°C. Microstructure of 100 rev min −1 samples having the lowest green density shows larger and more frequent porosity compared to higher green density samples with smaller and less visible porosity. The sample with 200 rev min −1 ball mill speed showed the highest Vickers hardness value followed by 150 and 100 rev min −1 in the range from approximately 60-150 Hv.

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Sodium potassium niobate (KNN) is the most promising candidate for lead-free piezoelectric material, owing to its high Curie temperature and piezoelectric coefficients among the non-lead piezoelectric. Numerous studies have been carried out to enhance piezoelectric properties of KNN through composition design. This research studied the effects of yttrium concentrations and lattice site occupancy preference in KNN films. For this research, the yttrium-doped KNN thin films (mol% = 0, 0.1, 0.3, 0.5, 0.7 and 0.9) were fabricated using the sol-gel spin coating technique and had revealed the orthorhombic perovskite structures. Based on the replacement of Y ions for K / Na ions, it was found that the films doped with 0.1 to 0.5 mol% of yttrium had less lattice strain, while films with more than 0.5 mol% of Y ions had increased strain due to the tendency of Y to occupy the B-site in the perovskite lattice. Furthermore, by analysing the vibrational attributes of octahedron bonding, the dopant occupancy at A-site and B-site lattices could be identified. O-Nb-O bonding was asymmetric and became distorted due to the B-site occupancy of yttrium dopants at high dopant concentrations of >0.5 mol%. Extra conduction electrons had resulted in better resistivity of 2.153× 10 Ω at 0.5 mol%, while higher resistivity was recorded for films prepared with higher concentration of more than 0.5 mol%. The introduction of Y improved the grain distribution of KNN structure. Further investigations indicated that yttrium enhances the surface smoothness of the films. However, at high concentrations (0.9 mol%), the yttrium increases the roughness of the surface. Within the studied range of Y the film with 0.5 mol% Y represented a relatively desirable improvement in dielectric loss, tan δ and quality factor, Q

In this article, the Magneto-Rheological (MR) automobile suspension is thoroughly reviewed. MR suspension has a smart behaviour of the fluid and it is preferred in many industries. The paper reviews the different model which was developed to represent the behaviour of MR suspension in automobile systems. This paper also presents the advantages, drawback and parameter estimation error for all proposed models. The conclusion of the intelligent model used to represent the behaviour of the MR automobile suspension systems also described.

If you would like to write for this, or any other Emerald publication, then please use our Emerald for Authors service information about how to choose which publication to write for and submission guidelines are available for all. Please visit www.emeraldinsight.com/authors for more information. About Emerald www.emeraldinsight.comEmerald is a global publisher linking research and practice to the benefit of society. The company manages a portfolio of more than 290 journals and over 2,350 books and book series volumes, as well as providing an extensive range of online products and additional customer resources and services.Emerald is both COUNTER 4 and TRANSFER compliant. The organization is a partner of the Committee on Publication Ethics (COPE) and also works with Portico and the LOCKSS initiative for digital archive preservation. AbstractPurpose -The purpose of this paper is to investigate the electrical conductivity and corrosion protection properties of a conductive coating composed of epoxy resin and carbon black in a sodium chloride (NaCl) solution. Design/methodology/approach -The conductive coating was prepared by combining epoxy resin, hardener, and carbon black. The electrical conductivity of the paint was studied with a DC current-voltage meter and field emission scanning electron microscopy. The corrosion protection properties of the paint were characterized by open circuit potential measurements and electrochemical impedance spectroscopy. Findings -The highest conductivity observed was 4.23 £ 10 2 4 Scm 2 1 for the coating containing 20 wt% carbon black. The coating protected mild steel in a 3.0 percent NaCl solution for up to five days. Originality/value -The results shown in this paper provide an insight into conductive paint and corrosion protection for future industrial applications and development.

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Bond strength evaluation of wire bonding in microchips is the key study in any wire bonding mechanism. The quality of the wire bond interconnection relates very closely to the reliability of the microchip during performance of its function in any application. In many reports, concerns regarding the reliability of the microchip are raised due to formation of void at the wire-bond pad bonding interface, predominantly after high temperature storage (HTS) annealing conditions. In this report, the quality of wire bonds prepared at different conditions, specifically annealed at different HTS durations are determined by measurements of the strength of the interface between the bond wire and the bond pad. The samples are tested in pull test and bond shear test. It was observed that the higher bonding temperature as well as the longer duration of HTS increased the bond strength. This is represented through the analysis of the measurements of ball shear strength. This is due to the fact that higher bonding temperature and longer HTS promoted better growth of the Cu-Al IMC layer. A transmission electron microscopy - energy dispersive X-ray analysis (TEM-EDX) has been carried out to observe the formation of the Cu-Al IMC layer in the sample.