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Significant amount of Ti-5553 alloy (a near-beta titanium alloy) swarf is produced during the daily operation of manufacturing high strength titanium alloy components used in industry. However, the direct use of the produced swarf is seldom investigated and reported. In this paper, hot pressing was used to recycle Ti-5553 machining swarf to turn the waste into useful material. The hot-pressed Ti-5553 alloy has an ultimate tensile strength (UTS) of 675 ± 12 MPa, strain to fracture of 0.98 ± 0.04%, and bending strength of 1181±28 MPa. After double-aging at 600 ºC for 4 h followed by 700 ºC for 0.5 h, both strength and ductility of hot-pressed Ti-5553 alloy have a significantly improved, with a yield strength (YS) of 1390 ± 20 MPa, UTS of 1425 ± 12 MPa, a strain to fracture of 2.47 ± 0.07%, and a bending strength 2565±35 MPa. These results demonstrate the hot pressing is a viable processing route to recycle Ti-5553 swarf to cost-effectively produce a qualified solid material for post-processing and engineering applications.

Background Light alteration affects the internal environment and metabolic homeostasis of the body through circadian rhythm disorders (CRD). CRD is one of the factors that induce and accelerate osteoarthritis (OA). Therefore, the aim of this study was to evaluate the effects of continuous dark-light (DL) cycle on joint inflammation, bone structure, and metabolism in normal and OA Sprague-Dawley (SD) rats. Methods Interleukin (IL)-1β, IL-6, inducible nitric oxide synthase (iNOS), and tumor necrosis factor (TNF)-α were used to evaluate the systemic inflammation in rats. The pathological changes and inflammatory reactions of the cartilage and synovium of the knee joint in rats were evaluated by Safranin O-fast green and immunological staining. Bone turnover was assessed by histomorphometry and μCT scanning, as well as bone metabolism markers and proteins. The expression changes of clock proteins BMAL1, NR1D1, PER3, and CRY1 in representative tissues were detected by western blotting. Results DL cycle significantly inhibited body weight gain in normal and OA rats. The levels of proinflammatory factors in the peripheral blood circulation and degradation enzymes in the cartilage were significantly decreased in OA+DL rats. DL cycle significantly destroyed the structure of subchondral bone in hindlimbs of OA rats and reduced trabecular bone numbers. The decrease of bone mineral density (BMD), percent bone volume with respect to total bone volume (BV/TV), trabecular number (TB.N), osteoclast number, and mineralization could also be found. The ratio of the receptor activator of nuclear factor-kappa B ligand/osteoprotegerin (RANKL/OPG) in the bone marrow of OA rats was markedly increased under DL, along with the activation of the mononuclear/phagocyte system. The expression of representative clock proteins and genes BMAL1, PER3, and CRY1 were markedly changed in the tissues of OA+DL rats. Conclusions These results suggested that DL cycle dampened the arthritis and promoted bone resorption and bone mass loss. Graphical abstract DL cycle affects bone turnover by regulating osteoclast production in osteoarthritic rats.

Novel micro-/nano-dual-scale porous composites have been fabricated for nanopollutant filtration by powder metallurgy via four-step sintering of Ti, Al, and Nb powders incorporated with SiO2/ZrO2/Y2O3/MgO/ZnO nanoparticles, respectively. Afterward, phase formation, surface morphology, and pore features of the porous composites have been characterized with the changes of heat-treatment temperatures and additive nanoparticles. The separation efficiency of as-prepared Ti-48Al-6Nb porous alloy and porous composite membranes for 50 mg/L TiO2 nanopollutants from pure water can be calculated through determining the change of TiO2 concentrations after filtration. Compared with the Ti-48Al-6Nb porous alloy membrane with a separation efficiency of 89.91%, all porous composite membranes can enhance the separation efficiency up to 99.80%. In particular, favorable contributions of the porous composite membrane with nano-SiO2 are further ascertained by maintaining a high separation efficiency of above 99.95% after repe...

This study investigated the performance of Amberlite IRC 748 resin in removing calcium ions from highly concentrated potassium chromate solution in a fixed bed column. The exchange capacity increased with initial calcium ion concentration and bed height but decreased as flow rate increased. Four different kinetic models, specifically the bed depth service time (BDST), mass transfer, Thomas, and Yoon-Nelson models, were applied to the experimental data to predict the breakthrough curves and determine the column parameters. The BDST model was extended to the prediction of service times of columns operated at different flow rates and influent concentrations; while the experimental and theoretical data points followed a similar trend, they deviated slightly from each other. The Thomas and Yoon-Nelson model predictions were in very good agreement with the experimental results for all the process parameters studied, indicating that they are suitable for use with these kinds of columns. (C) 2015 Elsevier B.V. All rights reserved.