The mechanism of grain fracturing in a zirconia metering nozzle used in the continuous casting process was studied. The phase composition, microstructure, and chemical composition of the residual samples were studied ...The mechanism of grain fracturing in a zirconia metering nozzle used in the continuous casting process was studied. The phase composition, microstructure, and chemical composition of the residual samples were studied using an X-ray fluorescence analyzer, scanning electron microscope, and electron probe. Results revealed that the composition, structure, and mineral phase of the original layer, transition layer, and affected layer of the metering nozzle differed because of stabilizer precipitation and steel slag permeation. The stabilizer MgO formed low-melting phases with steel slag and impure SiO2 on the boundaries（pores） of zirconia grains; consequently, grain fracturing occurred and accelerated damage to the metering nozzle was observed.展开更多
An experimental study on cutting amorphous alloy at nanometer scale is conducted by applying the principle and technology of scanning probe microscope(SPM) It is revealed from the experiments that cutting inside SPM...An experimental study on cutting amorphous alloy at nanometer scale is conducted by applying the principle and technology of scanning probe microscope(SPM) It is revealed from the experiments that cutting inside SPM is an excellent and direct way to research the material removal process at small size Based on the experimental results,the chip formation mechanism for the cutting of amorphous alloy is discussed It is found that the deformation along the direction of chip flow occurs ahead of the appearance of localized shear,and a simplified geometrical model is proposed to illustrate the deformation.展开更多
基金funded by the National Natural Science Foundation of China(51372193)the Natural Science Basic Research Plan in the Shaanxi Province of China(2014JM6224)
文摘The mechanism of grain fracturing in a zirconia metering nozzle used in the continuous casting process was studied. The phase composition, microstructure, and chemical composition of the residual samples were studied using an X-ray fluorescence analyzer, scanning electron microscope, and electron probe. Results revealed that the composition, structure, and mineral phase of the original layer, transition layer, and affected layer of the metering nozzle differed because of stabilizer precipitation and steel slag permeation. The stabilizer MgO formed low-melting phases with steel slag and impure SiO2 on the boundaries（pores） of zirconia grains; consequently, grain fracturing occurred and accelerated damage to the metering nozzle was observed.
基金This project is supported by Foundation of National Education Ministry for Returned Overseas Chinese Scholars(No.2000367) an
文摘An experimental study on cutting amorphous alloy at nanometer scale is conducted by applying the principle and technology of scanning probe microscope(SPM) It is revealed from the experiments that cutting inside SPM is an excellent and direct way to research the material removal process at small size Based on the experimental results,the chip formation mechanism for the cutting of amorphous alloy is discussed It is found that the deformation along the direction of chip flow occurs ahead of the appearance of localized shear,and a simplified geometrical model is proposed to illustrate the deformation.
