One important problem in casting wrought aluminum alloys is the high tendency to the formation of hot tears in the solidification *** using semi-solid metal(SSM) processing,the hot tearing tendency of alloys can be mi...
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One important problem in casting wrought aluminum alloys is the high tendency to the formation of hot tears in the solidification *** using semi-solid metal(SSM) processing,the hot tearing tendency of alloys can be minimized during *** the present research,the semi-solid slurry of wrought aluminum alloy 2024 was firstly prepared with a novel self-inoculation method(SIM),and then the microstructure characteristics of the semi-solid slurry and the rheo-diecastings cast with the semi-solid slurry were *** results indicate that finer and more uniform globular primary α-Al particles can be obtained when the semi-solid slurry are isothermally held for a short period within the semi-solid temperature range,and the primary α-Al particles without entrapped liquid are uniformly fine,globular grains in the *** holding temperature and time affect the solid fraction,particle size,and shape *** the semi-solid slurry is held at 625 ℃ for 3 min and 5 min,the optimal values for the average equivalent diameter are 70.80 μm and 74.15 μm,and for the shape factor are 1.32 and 1.42,*** solidification process of the rheo-diecastings is composed of the following two distinct stages:primary solidification process and secondary solidification *** secondary solidification process consists further of the following three stages:(1) direct growth of secondary primary(α 2) phase from the surface of the primary α-Al phase particles without re-nucleation,(2) independent nucleation and growth of α 3 phase from the residual liquid,and(3) eutectic reaction at the end.
Ti/Al2O3 composite of different components were prepared by Spark Plasma Sintering technique, mechanical and acoustical properties of Ti/Al2O3 composite were analyzed, weldability of Ti/Al2O3 composite with Mo and Al ...
Ti/Al2O3 composite of different components were prepared by Spark Plasma Sintering technique, mechanical and acoustical properties of Ti/Al2O3 composite were analyzed, weldability of Ti/Al2O3 composite with Mo and Al was also studied. The results indicate that 38.5vol%Ti/Al2O3 composite has good mechanical performance with relative density >99.20%, bending strength 897MPa, fracture toughness 17.38 MPam1/2 and micro-hardness 17.13GPa. The wave impedance of the composite was between which of Mo and Al, and the 38.5vol% Ti/Al2O3 welded well with Mo and Ti. These demonstrate that 38.5vol%Ti/Al2O3 composite could serve as one of interlayer materials in W-Mo-Al system graded flier-plate.
The effects of indium impurity on the crystal structure and bonding characteristics of In-doped β-Zn4Sb3 were investigated by powder X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The XRD Rietvel...
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The influence of Zn vacancy on lattice thermal conductivity of β-Zn4Sb3 is studied by non-equilibrium molecular dynamics approach. The lattice thermal conductivity of single-crystal bulk β-Zn4Sb3 decreases rapidly w...
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The leakage current, dielectric and loss properties of the integrated Pt/PbTiO3/PbZr0.3Ti0.7O3/PbTiO 3/Pt capacitors have been investigated. The capacitor has a same leakage mechanism as the film, in the low field reg...
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Well-ordered large-area two-dimensionally (2D) periodic and individually addressable metal-ferroelectric-metal (M/F/M) nanocapacitor arrays were fabricated by focused ion beam (FIB) milling with synchronal and serial ...
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In this paper, the particle co-sedimentation process is analyzed by discrete element analysis. The formation of deposits of continuous functionally graded materials derived from the particle co-sedimentation method is...
In this paper, the particle co-sedimentation process is analyzed by discrete element analysis. The formation of deposits of continuous functionally graded materials derived from the particle co-sedimentation method is simulated. The porosity of the deposit is calculated and the variation of the porosity along the deposition direction is obtained. From the simulation, the method to increase the deposit density is firstly generated, which is helpful for preparation of functionally graded materials by particle co-sedimentation method.
Transition-metal borides MB0.5(M = Co,Mo,V) were synthesized by high-speed mechanical ball-milling of the corresponding elemental metals and boron,and investigated as aqueous anode *** as-synthesized borides can achie...
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Transition-metal borides MB0.5(M = Co,Mo,V) were synthesized by high-speed mechanical ball-milling of the corresponding elemental metals and boron,and investigated as aqueous anode *** as-synthesized borides can achieve an excellent discharge capacity,about twice that of their parent transition *** metal boride electrodes also exhibit polarizations about 100-300 mV lower than those of their parent *** galvanostatic discharge curve of CoB0.5 shows a single discharge voltage plateau as a result of simultaneous electro-oxidation of elemental cobalt and/or amorphous cobalt *** MoB0.5 and VB0.5 show two well-defined voltage plateaus,corresponding to the electro-oxidation of the corresponding metal and *** results show that the coexisting transition metal and boride in the metal borides co-activate each other in the ball-milling process,thereby significantly enhancing their electrochemical performances.
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