Woyun Long

Luminescent properties of Tb3+ and Gd3+ ions doped aluminosilicate oxyfluoride glasses.

Tb(3+) and Gd(3+) ions doped lithium-barium-aluminosilicate oxyfluoride glasses have been prepared. The transmission, emission and excitation spectra were measured. It has been found that those Tb(3+)-doped lithium-barium-aluminosilicate oxyfluoride glasses exhibit good UV-excited luminescence. The luminescence intensity of Tb(3+) ion increases for those (Tb(3+), Gd(3+))-codoped glasses. Energy transfer process from Gd(3+) ion to Tb(3+) ion is indicated.

Research on Zr50Al15Ni10Cu25 bulk amorphous alloys prepared by mechanical alloying and low pressure sintering

Abstract Amorphous Zr50Al15Ni10Cu25 alloy powders were fabricated by mechanical alloying technique with commercially pure element powders. The effects of small amount of C, Si3N4 and SiC powders addition on the thermal stability and crystallisation behaviour of the Zr50Al15Ni10Cu25 amorphous alloy were investigated. The blended powders were compacted into bars by oil hydraulic press, and were sintered in argon atmosphere at different temperatures and pressures. The samples before and after sintering were characterised by X-ray diffraction, scanning electron microscopy, differential scanning calorimetry and electron tensile testing machine. The results demonstrated that a proper addition of Si3N4 powders to the amorphous matrix can improve the thermal stability of the matrix. Suitable additives can help to improve the density and mechanical properties of the matrix in sintering process.

Preparation of Zr50Al15−xNi10Cu25Yx amorphous powders by mechanical alloying and thermodynamic calculation

Amorphous Zr50Al15−xNi10Cu25Yx powders were fabricated by mechanical alloying at a low rotation speed from commercial pure element powders. The beneficial effect of Al partially substituted by Y in Zr50Al15Ni10Cu25 on glass-forming ability was investigated. The as-milled powders were characterized by X-ray diffraction and transmission electron microscopy. The results show that partial substitution of Al by Y can improve the glass-forming ability of Zr50Al15Ni10Cu25 alloy. Thermodynamic calculation of equivalent free energy shows that Zr50Al13·8Ni10Cu25Y1·2 alloy has the highest glass-forming ability, which is in good agreement with the report of orthogonal experiments.