Rolling texture and its effect on tensile property of a near-α titanium alloy Ti60 plate

Rolling texture and its effect on tensile properties of Ti60 alloy plates were investigated in the present study. The plates were β-rolled at 1070℃ and(α+β)-rolled at 980℃, using uni-directionally rolling(UDR) and cross-directionally rolling(CDR) processes, respectively.β-rolled plates exhibited weak textures, which were attributed to the dispersive orientations of secondary α during the β→α phase transformation. Strong deformation textures formed in(α+β)-rolled plates as a result of slipping mechanisms: the strong T-type texture in UDR plate was related to {10 1 0}[11 2 0] slipping, while the B-type texture in CDR plate was relevant with {0001}[11 2 0] slip. Strong T-type textures led to anisotropic tensile properties. B-type textures would decrease such an anisotropy. The(α+β)-CDR process was found to be a candidate process for reducing anisotropy of Ti60 alloy plates.

Properties of Xanthoceras sorbifolia Husk Fibers With Chemical Treatment for Applications in Polymer Composites

Surface science of natural fibers plays an important role in polymer/natural fiber composites. The Xanthoceras sorbifolia husk fibers were selected and chemically treated by sodium hydroxide(Na OH) solution,coupling agents,their combination,and the mixtures of acetic acid with hydrogen peroxide,respectively. 3-aminopropyltriethoxysilane(KH550),γ-methacryloxypropyltrimethoxylsilane(KH570) and organic titanate(JN-9A) were used as coupling agents in this work. Cellulose content was found to be increased after alkalization due to the removal of the non-cellulose substances,which was evidenced by attenuated total reflectance-Fourier transform infrared(ATR e FTIR) spectroscopy spectrum analysis and thermogravimetric analysis(TGA) measurements. The highest cellulose content was obtained in the bleached fibers. TGA analysis revealed an improvement in thermal stability of the treated fibers,especially for alkali-KH570 treated fibers. The tensile strength of the alkali-KH570 treated fiber and the alkali-bleached fiber were higher than that of other fibers due to high cellulose content and high crystallinity.

Fabrication of three dimensional SiC@C hybrid for efficient direct dehydrogenation of ethylbenzene to styrene

Synthesis of hybrid carbon materials with core-shell structure and robust catalytic performance is of great research interest,and remains a great challenge in catalytic dehydrogenation of hydrocarbons reaction.In this paper,few-layer sp^(2) carbon decorated SiC nanocrystals with core-shell structure(SiC@C)were fabricated through a dual-confined magnesiothermic method by employing glucose and SiO_(2) as precursors.The SiC@C nanocrystals were further crosslinked to be a three dimensional(3D)mesoporous hybrid by the in situ generated carbon as binders and exhibiting a 410.30 m^(2) g^(−1) large surface area.The as-prepared SiC@C hybrid materials as metal-free catalysts were evaluated in the steam-free direct dehydrogenation of ethylbenzene to styrene.Benefiting from the abundant surface carbonyl groups on the graphite carbon layers,the optimized yield rate of styrene normalized by carbon mass was as high as 11.58 mmol g^(−1) carbon h^(−1),nearly 4 times that of nanodiamonds.Considering the low cost and excellent catalytic activity,the hybrid 3D SiC@C material may be a promising candidate for direct dehydrogenation of hydrocarbons.