Journal of Materials Research
The morphology of the dark and bright regions observed by transmission electron microscopy for the Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass strongly depends on the ion beam parameters used for ion milling. This indicates that the ion beam could introduce surface fluctuation to metallic glasses during ion milling.
关键词:
room-temperature
Ximiao PAN
,
Zhanpeng JIN
材料科学技术（英文）
The phase equilibrium relations of the ternary Ni-Cr-Zr system at 900°C have been investigated by means of diffusion triple and electron probe microanalysis (EMPA) techniques. A series of tie lines and triangles have been determined, and the corresponding tentative isothermal section is presented based on the current information.
关键词:
Nickel
,
null
,
null
,
null
Journal of Alloys and Compounds
The subsolidus phase relations in the ZnO-MoO3-B2O3, ZnO-MoO3-WO3 and ZnO-WO3-B2O3 ternary systems have been investigated by the means of X-ray powder diffraction (XRD). There is no ternary compound in all the systems. There are five binary compounds and five tie lines in the ZnO-MoO3-B2O3 system. This system can be divided into six 3-phase regions. There are three binary compounds and three tie lines in the ZnO-MoO3-WO3 system. This system can be divided into four 3-phase regions. There are four binary compounds and four tie lines in the ZnO-WO3-B2O3 system. This system can be divided into five 3-phase regions. The possible component regions for ZnO single crystal flux growth were discussed. The phase diagram of Zn3B2O6-ZnWO4 pseudo-binary system has been constructed, and the result reveals this system is eutectic system. The eutectic temperature is 1007 degrees C and eutectic point component is 70 mol% Zn3B2O6. (c) 2007 Elsevier B.V. All rights reserved.
关键词:
ZnO-MoO3-B2O3;ZnO-MoO3-WO3;ZnO-WO3-B2O3;Zn3B2O6-ZnWO4;phase relation;zno single-crystals;zinc oxide;growth;moo3-wo3
Surface & Coatings Technology
In order to reduce the high brittleness of laser clad Fe-B coatings, the composite Fe-Ti-B coating was developed by laser cladding with a powder mixture of B4C and Fe-Ti alloy. The microstructure, hardness and cracking resistance of these coatings were investigated in this paper. The experimental work enables the following findings to be reached: (i) the needle-like TIE, whiskers could be synthesized in situ using the laser cladding method in the composite Fe-Ti-B coating. (ii) The size, shape and volume fractions of TiB2 whiskers in the composite coating are greatly dependent upon powder compositions (contents of B, Ti elements and the ratio of B/Ti elements) and the laser energy density used. The average ratio of width/length for the synthesized TiB2 whiskers increases with increasing laser energy density and ratio of B/Ti elements in this coating. (iii) Both the hardness and cracking resistance of the Fe-B laser clad coating could be improved by the formation of TIE, whiskers. (C) 2001 Elsevier Science B.V. All rights reserved.
关键词:
TiB2;laser cladding;coating;steel;microstructure;powders
材料科学技术（英文）
The effect of interstitial hydrogen on the cohesion of the Al Sigma=11(113) grain boundary (GB) is investigated based on the thermodynamic model of Rice-Wang using the first-principles density function calculation. The results indicate that interstitial H behaves as an embrittler from "strengthening energy" analysis. The reduced GB cohesion due to the presence of H at the GB is attributed to the low affinity between H and Al, and the weakened bonding of Al atomic pairs perpendicular to GB plane.
关键词:
hydrogen;grain boundary;Al-Mg alloys;pseudopotentials;1st-principles
Xiaoguang LIU
,
Xiaowei WANG
材料科学技术（英文）
The effect of interstitial hydrogen on the cohesion of the Al ∑=11(113) grain boundary (GB) is investigated based on the thermodynamic model of Rice-Wang using the first-principles density function calculation. The results indicate that interstitial H behaves as an embrittler from "strengthening energy" analysis. The reduced GB cohesion due to the presence of H at the GB is attributed to the low affinity between H and Al, and the weakened bonding of Al atomic pairs perpendicular to GB plane.
关键词:
Hydrogen
,
null
,
null
Haihua LIU
金属学报(英文版)
doi:10.1016/S1006-7191(08)60120-9
A novel method was reported to measure the remnant magnetic field in Lorentz mode in a FEI Tecnai F20 transmission electron microscope equipped with a Lorentz lens. The movement of the circle Bloch line of the cross-tie wall in Permalloy is used to measure the remnant magnetic field by tilting the specimen and adjusting the objective lens current. The remnant magnetic field is estimated to be about 17 Oe, in a direction opposite to that of the objective lens magnetic field. The remnant magnetic field can be compensated by adjusting the value of the objective lens current.
关键词:
Lorentz electron microscopy
,
Lorentz lens
,
remnant magnetic field
,
Permalloy
,
cross-tie walls
Physical Review B
By use of the linear-combination-of-atomic-orbital (LCAO) method for a cluster model, we studied the electronic structure of gamma-from Sigma 11 [1 (1) over bar0](11 (3) over bar) grain boundary doping with N and Mn atoms. The effect of the segregation on the cohesion of the grain boundary is investigated based on the Rice-Wang thermodynamic model. It is found that N could not only largely enhance the cohesion of the grain boundary but also eliminate the detrimental effect of Mn. The cosegregation effect of Mn and N on the cohesion of the grain boundary depends on where they segregate. Nitrogen could be reliably used in alloyed steels as an efficient strengthening element.
关键词:
electronic-structure;phosphorus segregation;stainless-steel;embrittlement;austenite;nitrogen;boron;impurities;fracture;metals
