112 resultados para Firing (Ceramics)


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采用传统陶瓷烧结工艺,在无压还原气氛中低温制备了Yb^3+掺杂量高达10%(按摩尔计)的透明性良好的氧化镧钇激光陶瓷,研究了其在室温的吸收光谱、发射光谱以及荧光寿命。结果表明:掺Yb^3+氧化镧钇透明激光陶瓷具有宽的吸收和发射光谱以及长的荧光寿命。吸收峰位于902,942nm和968nm处,吸收截面分别为0.31×10^-20,0.45×10^-20cm^2和0.53×10^-20cm2:主发射峰位于1032nm和1075nm处,发射截面分别为1.05×10^-20cm^2和0.87×10^-20cm ^

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采用传统无压烧结工艺制备出透明性良好的掺Cr3+氧化铝陶瓷;测定了陶瓷的吸收光谱、发射光谱和激发光谱。结果表明,氧化铝陶瓷吸收峰与红宝石单晶一致,吸收截面大小与单晶相近;陶瓷中Cr3+离子所处格位的晶体场强较单晶弱,但其发射谱仍有较好的锐线发射;陶瓷中微量添加剂以及晶界的存在使得Al2O3晶胞发生畸变,造成其发射峰宽化。

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It was first reported the spectral properties of a low-temperature sintered transparent Yb: Y2-2x La-2x O-3 laser ceramics. Yb: Y2-2x La-2x O-3 laser ceramics have broad absorption band and large absorption cross- section of 4.0 x 10(-20) cm(2) at wavelengths 977nm of the highest absorption peak. Its fluorescence lifetime is 1.1 ms, and the emission cross-sections are 1.0 x 10(-20) cm(2) and 0.7 x 10(-20) cm(2) at wavelengths 1033nm and 1077nm, respectively. All the optical properties are similar to those of single crystals.

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采用传统无压烧结工艺在氢气氛下制备Al2O3透明陶瓷。实验结果表明:MgO和La2O3复合添加时,随着La2O3掺杂量的增加体积密度总体上保持上升的趋势。随着保温时间的延长,陶瓷的致密化程度增大,残余气孔逐步排出,晶粒进一步长大。采用La2O3和MgO复合添加比单独掺入MgO陶瓷样品透过率更高,掺杂效果更好。在烧结温度为1750℃,保温时问为1h条件下,在波艮为300~800nm测试范围内,陶瓷样品的全透过率大于82%,最大值为86%。

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采用传统无压烧结工艺制备出透明性良好的掺Ti氧化铝陶瓷;测定了该陶瓷的吸收光谱、荧光光谱和激发光谱。结果表明,掺Ti氧化铝透明陶瓷样品在Mg与Ti掺入离子的摩尔比(NMg/NTi)较小时,表现出Ti^3+离子的490nm特征吸收峰,即^2T2→^2E跃迁产生的宽带吸收;NMg/NTi较大时,陶瓷样品吸收光谱中不存在Ti^3+离子吸收,其250nm处吸收为O^2-→Ti^4+的转移吸收。掺Ti氧化铝透明陶瓷样品Ti^3+离子的发射谱线与单晶的相吻合,同时Ti^3+在氧化铝陶瓷中分布很均匀,且Ti^3+浓度较

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采用传统无压烧结工艺制备出透明性良好的掺Cr的Al2O3透明陶瓷;测定了其吸收光谱和荧光光谱,发现在Al2O3六配位的八面体结构中,除了有Cr^3+离子的特征吸收峰外,由于有Mg^2+的电荷补偿作用,也有Cr^4+离子,Cr^4+的荧光发射峰位于1223nm附近,与Cr^4+在四面体中的发光行为一致。但其荧光发射峰较窄,半高宽△λ仅为37nm。

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Transparent polycrystalline Nd:YAG ceramics were fabricated by solid-state reactive sintering a mixture of commercial Al2O3,Y2O3, and Nd2O3 powders. The powders were mixed in ethanol and doped with 0.5 wt% tetraethoxysilane, dried, and pressed. Pressed samples were sintered at 1750 degrees C in vacuum. Transparent fully dense samples with average grain sizes of 10 mu m were obtained. The 1 at.% Nd:YAG ceramic was used to research passively Q-switched laser output with a Cr4+:YAG crystal as a saturable absorber. An average output power of 94 mW with a pulse width of 50 ns was obtained when the incident pump power was 750 mW. The slope efficiency was 13%. The pulse energy is 5 mu J, and the peak power is about 100 W.