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The influence of silicon carbide (SiC) addition to W-Ni-Cu-based heavy alloys has been investigated in the present study. The powders of W-Ni-Cu with varying percentages of SiC were blended and sintered using conventional and Spark Plasma Sintering (SPS) techniques. The sintered samples were characterized to determine the density, microstructure, and mechanical properties. The alloy (W-7Ni-3Cu-0.5SiC) exhibits high ultimate tensile strength 430 MPa for conventional sintering and 831 MPa for spark plasma sintering, relative sintered density 71.84% and 88.25% of conventional sintered and spark plasma sintering, respectively. After the tensile test, the fracture surfaces show a mixed-mode fracture consisting of brittle W/W intergranular and ductile mode of fracture in the matrix.

This work deals with processing, characterization, and study of the mechanical property of AA6061-ZrO2 composite by stir casting unit combined with squeeze casting setup. Morphology study of the refined composite was measured with the help of Optical Microscope and Scanning Electron Microscopy (SEM). The Energy Dispersive x-ray spectroscopy was performed to observe the desirable elements present in the processed composite. The EDX investigation endorses the presence of Aluminum, Zirconium, and Oxygen, are the elements of the desirability. The processed composite displayed increased hardness value when related to the base aluminum alloy AA6061 at test conditions. The tensile tests have been performed for the refined specimen both in cast and heat treated conditions. 20%–63% improvement in tensile strength as an outcome of the inclusion of ZrO2 particles and heat treatment process was recorded, and the fashion was analyzed. Finally, all the three composite specimens were tested for wear resistance property for the support of pin on disc wear test kit. The wear trend due to the addition of ZrO2 particles was discussed in a detailed manner.

Micro total analysis systems (μTAS) have been developed to perform a number of analytical processes involving chemical reactions, separation and sensing on a single chip. In medical and biomedical applications, μTAS must be designed considering special transport mechanisms to move samples and reagents through the microchannels in the system. For conventional micropumps, however, complicated relationships exist between the pumping mechanisms, the conditions under which the devices operate and the behavior of the multi-component fluids transported in these channels. A bi-directional microfluid driving system has been developed in this paper. This pneumatic system is an on-chip planar structure with no moving parts and does not require microfabricated heaters or electrodes. The pumping actuation is introduced to the microchannel fabricated in the chip by blowing an airflow through this device. The bi-directional driving module combines two individual components for suction and exclusion. The driving system provides a stable and flexible bi-directional microfluid driving control. The tunable parameters for adjusting the exclusion/suction ratios, such as the location of the inlet channel and the velocities of the airflow, have been observed in the numerical study. The optimal exclusion/suction ratio for the specific purpose of the driving system can be selected by changing the location of the microchannel to the reaction area for the sample/reagent. The velocity at the microchannel can be adjusted by varying the inlet velocities for the suction and exclusion components. For the presented design, no air conduit was employed to connect the servo-system to the driving system; therefore the packaging difficulty and leakage problem, which may arise in conventional systems, can be eliminated. The final airflow outlet was fixed in one direction so that it can prevent cross-contamination between the servo-system and the chip. The driving system is therefore particularly suited to microdevices for biochemical analysis.

Effects of phase change in the recording layer due to temperature changes and the material parameters used in the simulated transient temperature distributions were examined. The initial structure of the recording layer was the key parameter for simulated temperature distributions in both the erasing and writing processes. Latent heat due to the phase change had little effect on the transient temperature distributions, however, the temperature-dependent heat capacity had significant effects and resulted in a transient temperature distribution level lower than that using a constant room-temperature capacity value. From the simulated transient temperature profile, cooling rate, dependence of phase-changed spot size on the laser power and laser pulse duration, as well as the phase-change characteristics in the phase-change optical disk, could be obtained. By applying proper material parameters, the disk with a hydrogenated amorphous carbon film as the top dielectric layer with a disk structure of PC/ZnS–SiO2(111 nm)/GeSbTe(20 nm)/α–C:H (63 nm)/Al(70 nm) showed less temperature variation between the center and the edge of the irradiated spot than that of a disk with a conventional disk structure of PC/ZnS–SiO2(144 nm)/GeSbTe(20 nm)/ZnS–SiO2(21 nm)/Al(70 nm). Less temperature variation may give rise to a written spot with more uniform microstructures.