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An analysis has been carried out to study an unsteady MHD convective non-Newtonian fluid flow in the presence of heat source and radiation absorption. The governing partial differential equations along with the boundary conditions are first cast into a dimensionless form and then the equations are solved by closed analytical method. The effect of various physical parameters like porous permeability, Prandtl number, heat source, radiation absorption, diffusion-thermo, Schmidt number and chemical reaction parameter on velocity, temperature and concentration profiles are presented graphically. The effects of all these parameters on wall velocity gradient, wall temperature gradient and wall concentration gradient are also discussed with the help of tables. Temperature increases in the presence of heat source, radiation absorption parameter and Dufour number while decrease in the presence of Prandtl number and radiation parameter.

Among various cold expansion methods, Split Sleeve Cold Expansion technique is widely used. This method induces a zone of compressive residual stresses by pulling an oversized mandrel followed by removal through the hole. An appropriate amount of compressive residual stress reduces the severity of tensile stresses acting on the components there by retarding the fatigue crack growth rate or extending the service life of the components. It has been observed that either extensive testing or special computer codes (AFGROW) are required to determine fatigue crack growth life around residual stress fields. There was no generalized procedure to predict fatigue crack growth life around residual stress fields of cold expanded holes. An attempt has been made in this work to develop a systematic, simplified method to predict fatigue crack growth life around cold expanded holes by combining finite element method and Willenborg’s model. This method was in very good agreement to the classical approach and the variation of predication of fatigue crack growth was about 5.77% compared to the classical approach. The outcome of this work is the development of a systematic and simple procedure for predicting fatigue crack growth life around cold expanded fastener holes. This procedure helps in recommending appropriate inspection intervals and extending the service life of fatigue prone fastener holes.

In this paper, we propose a Haar wavelet approach for solving strongly nonlinear oscillators. The proposed method presents an alternative approach to overcome the difficulty of capturing the periodic behavior of the solution, which is characteristic of oscillator equations, and to give a good approximation to the true solution in a very large region. To determine the validation and accuracy of the proposed method, we compare the proposed results with the existed results.In this paper, we propose a Haar wavelet approach for solving strongly nonlinear oscillators. The proposed method presents an alternative approach to overcome the difficulty of capturing the periodic behavior of the solution, which is characteristic of oscillator equations, and to give a good approximation to the true solution in a very large region. To determine the validation and accuracy of the proposed method, we compare the proposed results with the existed results.

Aluminium being light weight metal used widely in many engineering applications. It’s being a highly ductile material in its purest form also limits its applications in load carrying members. Addition of alloying elements like nickel and silicon carbide can make aluminium a better material for many applications. In this work aluminium metal matrix composite is prepared by adding nickel powder of 30 microns4% and silicon carbide of 45 microns in 2,4,6and 8% by weight of matrix material. Composite was prepared by using a powder metallurgy (PM) at room temperature compaction. The compaction load was optimized to 15tonns for successful fabrication of green specimen; these green specimens were sintered in a furnace to 5400 temperatures and furnace cooled. It was found that reinforcement of nickel and silicon carbide significantly improved the mechanical properties of the composite; hardness is improved by 35% in that compaction load. Wear rate of the composite is reduced from 200 micrometers to 50 micrometers for 5000 meters of track length at a load of 5N. The prepared composite also shown a uniform distribution of reinforcement particle in the matrix material under micro structural studies.Aluminium being light weight metal used widely in many engineering applications. It’s being a highly ductile material in its purest form also limits its applications in load carrying members. Addition of alloying elements like nickel and silicon carbide can make aluminium a better material for many applications. In this work aluminium metal matrix composite is prepared by adding nickel powder of 30 microns4% and silicon carbide of 45 microns in 2,4,6and 8% by weight of matrix material. Composite was prepared by using a powder metallurgy (PM) at room temperature compaction. The compaction load was optimized to 15tonns for successful fabrication of green specimen; these green specimens were sintered in a furnace to 5400 temperatures and furnace cooled. It was found that reinforcement of nickel and silicon carbide significantly improved the mechanical properties of the composite; hardness is improved by 35% in that compaction load. Wear rate of the composite is reduced from 200 micrometers to 50 micrometers ...

Fracture toughness, Hardness and Tensile Strength of the Aluminum alloy 7075-T6 coated with Cadmium with varying thickness of 10µ and 20µ were investigated. Electroplating Cadmium coating process gives excellent corrosion resistance, provides low coefficient of friction which increases the surface hardness of the material. It also provides a uniform and dense coating, in many cases, maintains surface finish as it was before plating. The specimens prepared in line with ASTM E-8M and E-399 standard were subjected to various tests. The results shows thatthe hardness of the EC coted specimens has increased by 10% and increases with increase in thickness, butthe thicker the EC coating, more brittle is the material. The Ultimate Tensile Strength also increased by 5% compared to the uncoated counterpart. There was a steep increase in plain strain fracture toughness with the increase in the coating thickness for the Aluminum 7075–T6 alloy in TL orientation. The crack growth was Unstable due to the strong adhesion between the EC coating and the alloy.

This investigation mainly targeted on study of hardness and tensile properties of Al 7075 with different metal coatings like Nickel, Zinc and cadmium. Coating of these metals on Al 7075 is successfully achieved by time dependent electroplating method for different thicknesses of 10, 15 and 20 Microns. These metal coated Al-7075 specimens were tested for hardness and tensile properties according to the ASTM standards. It’s found that Nickel coated alloy shows excellent hardness and tensile properties compared to Zinc and Cadmium coated alloys. 20 µm Nickel coated alloy exhibits highest hardness number of 102 HRB and Maximum Tensile Strength of 603 MPa than Zinc and Cadmium coated alloy. The microstructural studies authenticated that the coating of Nickel, zinc and cadmium on Al 7075 is homogeneous.

A comprehensive approach to determine the mechanical properties of advanced thermoelectric materials is described. The focus of this paper is the mechanical characterization of skutterudites, i.e., LTN‐SKD (n‐type doped CoSb3) and LTP‐SKD (p‐type CeFe3−xRuxSb3). Properties such as the elastic modulii, flexural strengths and fracture toughness, are reported and discussed. A summary table of the key mechanical properties is provided.

GaN is one of the most promising electronic materials for applications requiring high-power, high frequencies, or high-temperatures as well as opto-electronics in the blue to ultraviolet spectral region. We have recently measured depth profiles of Mg, Si, and Zn implants in GaN substrates by the TEAMS particle counting method for both matrix and trace elements, using a gas ionization chamber. Trace Element Accelerator Mass Spectrometry (TEAMS) is a combination of Secondary Ion Mass Spectrometry (SIMS) and Accelerator Mass Spectrometry (AMS) to measure trace elements at ppb levels. Negative ions from a SIMS like source are injected into a tandem accelerator. Molecular interferences inherent with the SIMS method are eliminated in the TEAMS method. Negative ion currents are extremely low with GaN as neither gallium nor nitrogen readily forms negative ions making the depth profile measurements more difficult. The energies of the measured ions are in the range of 4-8 MeV. A careful selection of mass/charge ratios of the detected ions combined with energy-loss behavior of the ions in the ionization chamber eliminated molecular interferences.

Continuous miniaturization of integrated circuits requires narrower dopant profile depth in the Si channel and consequently the use of ultra‐shallow implants in the manufacturing process. Secondary Ion Mass Spectroscopy (SIMS) is routinely used to measure the boron depth concentration profiles. However, due to the altered nature of the near‐surface sputtering process inherent to SIMS, it underestimates the B implanted doses for implantation energies below 2 keV. Alternate ion beam methods for absolute dose measurements of ultra‐shallow implanted As and B in Si are presented in this study. The dopant implant energies ranged from 250 eV, to 5 keV for boron and from 500 eV to 5 keV for arsenic. Implanted doses for both B and As varied from 2 × 1013 to 1 × 1015 atoms/cm2. The arsenic implants were studied with Rutherford Backscattering Spectrometry (RBS) using 2 MeV carbon ions. The absolute arsenic implanted doses were measured to an accuracy of better than 5%. The 1 keV arsenic implants were extensively studied for radiation damage with a 12C beam. No appreciable arsenic dose loss was observed during C irradiation for an integrated charge of ⩽ 80 μC, which was the maximum used for these studies. For the B implants, Elastic Recoil Detection (ERD) was used with 14 MeV F4+ ions. A 9.4 μm Mylar foil was found to adequately stop the scattered 19F ions and give good energy separation for the 11B recoiled ions. The absolute dose measurements are ∼ 5% for the 5 keV 11B implants. Significant radiation damage was observed for the ultra shallow implants and the measured B dose has been obtained by extrapolation to the zero integrated charge of the beam. The absolute boron dose measurements of the ultra shallow (250 eV) implants were determined with an accuracy better than 10%.