In the present work, erosion wear due to slurry mixture flow has been investigated using a slurry erosion pot tester. Erosion tests are conducted on three different slurry pipe materials, namely, mild steel, SS202, and SS304, to establish the influence of rotational speed, concentration, and time period. In order to increase erosion wear resistance, a high-velocity oxy-fuel (HVOF) coating technique is used to deposit a WC-₁₀Co₄Cr coating on the surface of all piping materials. Experimental results show that rotational speed is a highly-influencing parameter for the erosion wear rate as compared to solid concentration, time duration, and weighted mean diameter. WC-₁₀Co₄Cr HVOF coating improved the erosion resistance of piping materials up to 3.5 times. From experimental data, the exponents of solid concentration, velocity, and the size of particles are calculated for the empirical erosion wear equation. A functional equation of the erosion wear rate is developed. The predicted erosion wear is in agreement with the experimental data and found to be within a deviation of ±12%.

Medical implants and other biomaterials are used by millions of individuals all over the globe to restore lost bodily functions due to injury or illness. Many of these implants fail after a short time or have difficulties, despite the fact that they play important roles in keeping a person's life safe or increasing the quality of their lives. It is the lack of biocompatibility that has proven to be the biggest downfall of biomaterials. Investments in this industry may be made using a thin film of hydroxyapatite powder (HAP) on stainless steel. Plates, screws, pins, and artificial joints are only some fixation devices for bones that often use 316L stainless steel. However, due to its unique advan­tageous qualities such as super-elasticity and low-profile feature, thin film HAP signals a high potential for use in compact new cardiac devices like the cardiovascular system and protecting stent grafts.

The present study was carried out in an attempt to reduce head loss in 90° pipe bends for conveying coal-water slurry suspensions using computational fluid dynamics (CFD). Bend geometries were modified by altering the r/D ratios within the range of 1.5–3.0. Numerical simulations were performed using several turbulence models for a solid concentration range of 30–60% (by weight) and the results were validated with experimental data. An Eulerian multiphase model along with an SST k-ω turbulence scheme was found most appropriate and shows decent agreement with experimentation results. The mean sizes of coal particles were taken as 16 μm. Results show that head loss was increased with flow velocity and solid concentration. It was also observed that r/D ratio has a significant impact on head loss characteristics. The minimum drop in head loss was observed in a pipe bend having an r/D ratio of 2.0. The effect of flow separation and secondary flows on turbulence, flow velocity and distribution of the solid suspension inside the bend geometry was also studied with the help of contours.

The present study investigates head loss for flow of coal–water slurry inside 90° pipe bend. The experiments were conducted with slurries of different solid concentrations, varying from 31.4 to 60.8% (by weight). Pulverized coal samples with particle sizes of less than 53 µm were used to prepare the slurry. During experimentation, average flow velocity was kept in the range of 2–5 m/s. Extensive rheological experimentation was performed to analyze the flow characteristics of coal–water slurry with and without the addition of additive namely sulfonic acid. Sulfonic acid was mixed with coal–water slurry in proportions of 1–4% (by weight) at higher concentrations (i.e., 60.8%). Coal–water slurry showed Newtonian behavior at low concentrations of 30%; above, it shows pseudoplastic behavior. The head loss across the pipe bend increases as the solid concentration of slurry increases and decreases as the proportion of an additive increases. Losses occurring in bend curves were given in terms of bend loss coefficient. The bend loss coefficient decreased as flow velocity increased and increased as solid concentration increased. The present study also highlights the role that solid concentration plays with regard to settling velocity of coal–water slurry. A trend of decreasing settling velocity was observed while the solid concentration (by weight) of the slurry was increased.

Recently, magnesium alloys have garnered a lot of interest as a potentially useful material for applications involving biodegradable implants. Cracking or fracture of metal-based implants under the combined action of corrosion and mechanical stresses, namely stress corrosion cracking (SCC) is an obviously critical criterion before any new material might be deployed as implants. Cracking or fracture of metal-based implants occurs under the simultaneous action of corrosion and mechanical stresses. This article gives a review of the existing literature on the SCC of magnesium alloys in corrosive environments, including simulated body fluid and the accompanying fracture process. It also indicates the knowledge gap that exists in this area of research. In addition, a high-level review of the preventative measures that may be taken to avoid potential corrosion fatigue failures in magnesium alloys is provided.

Batch studies carried out at varying pH, metal concentrations, temperature, particle size, and contact times indicate 75% removal of Zn