Study Of YAG And Yb:YAG Tranparent Laser Ceramic Preparation And Optical Properties

Yttrium aluminum garnet (Y3Al5O12, YAG) has the very good mechanical properties and optical properties, is a kind of ideal laser matrix material.About powder preparation technology, molding technology and preparation of transparent ceramics sintering technology has been the focus of attention at home and abroad. This thesis mainly studies the vacuum sintering solid phase reaction method and chemical copre cipitation preparation process of transparent ceramics and the relationship between performance. Mainly includes the following several aspects:1. Through the method of solid instead should be vacuum sintering YAG ceramics, system research of ball grinding parameters, the dosage of additives, sintering process on the transparent YAG ceramic microstructure and optical properties. Experimental results show that the ball mill speed of 160 r/min, after the ball mill powder mixing, vacuum sintering preparation of transparent ceramics grain size uniformity, no porosity, light transmittance in the visible band of 60%; Adding MgO style as sintering additives (optimum adding amount was 0.1 wt%), reduce the sintering temperature, refining the grain size, increase the number of grain boundary, promote stomatal ruled out. Sintering temperature is 1750℃, holding time of 5 h when preparation of YAG transparent ceramic optical performance, best for subsequent doped with rare earth ions provide technical guarantee.2. The use of the previous process parameters, using the method of solid instead should be vacuum sintering Yb:YAG transparent ceramics. The results show that through the way of nitrates in the form of doping Yb3+ than was prepared by means of oxide forms doping Yb3+ ceramic relative density is higher, pervious to light performance is better; With the increase of doping Yb3+ concentration, ceramic grain size distribution is more homogeneous, but light transmittance and the relative density of the ceramic is irregular change, of which 5 at% Yb doped, ceramic light transmittance and the relative density of the highest. All samples after 1700℃ sintering only YAG phase, there is no other impurities. When doping concentration is 1 at%, the best sintering temperature is 1650℃ are lower than those of YAG ceramic sintering temperature.3. Ammonium bicarbonate as precipitant, by chemical coprecipitation preparation YAG andYb:YAG nano-powder. Results show that the increased slightly chinalco ion concentration of reaction solution, namely when Y3+：oncentration of Al3+ for now, the precipitation reaction of precursor after 1200℃ calcination 3 h can form no impurity phase of pure cubic phase YAG nano powder, the powder dispersivity is good, the shape of rod, the average particle size is about 150 nm. Using the homemade YAG powder by vacuum sintering YAG transparent ceramics, pure phase of YAG powder sintering of ceramics is pervious to light; Different doping concentration of Yb:YAG ceramics with the increase of doping amount of grain size also increased, by fluorescence spectrum analysis,30 at% Yb3+ doping concentration quenching effect has not taken place, on the surface of Yb can achieve high levels of doping, is advantageous to the preparation of the high power solid laser.