Structure, mechanical properties and grindability of a series of binary Ti-Zr alloys with zirconium contents ranging from 10 to 40 wt% have been investigated. Commercially pure titanium (c.p. Ti) was used as a control. Experimental results indicated that the diffraction peaks of all the Ti-Zr alloys matched those for alpha Ti. No beta-phase peaks were found. The hardness of the Ti-Zr alloys increased as the Zr contents increased, and ranged from 266 HV (Ti-10Zr) to 350 HV (Ti-40Zr). As the concentration of zirconium in the alloys increased, the strength, elastic recovery angles and hardness increased. Moreover, the elastically recoverable angle of Ti-40Zr was higher than of c.p. Ti by as much as 550%. The grindability of each metal was found to be largely dependent on the grinding conditions. The Ti-40Zr alloy had a higher grinding rate and grinding ratio than c.p. Ti at low speed. The grinding rate of the Ti-40Zr alloy at 500 m/min was about 1.8 times larger than that of c.p. Ti, and the grinding ratio was about 1.6 times larger than that of c.p. Ti. Our research suggested that the Ti-40Zr alloy has better mechanical properties, excellent elastic recovery capability and improved grindability at low grinding speed. The Ti-40Zr alloy has a great potential for use as a dental machining alloy.

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Gelatin nanofibers (GNs) prepared by electrospinning were cross-linked with glutaraldehyde vapor to improve their water-resistant ability. After cross-linking treatment, the form of the fibers expressed no substantial change, but the average diameter of the fibers increased with increasing cross-linking time. The swelling induced by the moisture during the cross-linking process was moderated when the cross-linking time reached 45 min. The contact angle measurements confirmed that the electrospun gelatin fibers were more hydrophilic than the gelatin film (GF). Increasing the cross-linking time did not alter the hydrophilic properties of the gelatin fibers. The cell compatibility was evaluated based on 3-(4,5-dimethylthiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay, scanning electron microscope and confocal microscope observations, and Western blot analysis by culturing MG-63 cells on the GFs and GNs. The nanofibrous structure fabricated by an electrospinning technique was found to enhance cell adhesion and proliferation. This process is a cost-effective simulation of GN structures’ promising applications on scaffold preparation for tissue engineering.

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