No abstract

By progressive weight percent substitution of Na2O for Li2O, at a constant ratio of concentration of CaO, Al2O3, and GeO2, the Li2O(–Na2O)–CaO–Al2O3–GeO2 system is prepared for infrared transmitting germanate glasses. The optical and chemical durability properties of these glasses have been studied. The infrared cutoff for these germanate glasses is about 7.2 µm longer than that of 5 µm for silicate glasses. The ultraviolet absorption edge for these glasses is near 306 nm, except for the glass which contained 6.44 wt% Na2O at 295 nm. The refractive indexes of these germanate glasses increase as Na2O content is increased. The Abbe number for all glass samples is about 62.03±4.07. The absorption coefficients for these germanate glasses at 2.5 µm and 500–700 nm are 0.023 mm-1 and 0.019 mm-1, respectively. The leaching results indicate that the glass with 3.22 wt% Na2O ( C3 glass) has the minimum weight loss in the chemical durability test.

The debinding process in the case of metal injection molding for fabrication of the Fe–6Ni–4Cu compact and variables such as temperature and time has been studied. The debinding process of multiple organic binders in the Fe–6Ni–4Cu compact was investigated by thermal gravimetric analysis (TGA) weight loss and mercury porosimetry analysis. The weight loss of wax and SA dramatically increases from below 10 wt% to 76.0 wt% and 86.0 wt% after immersion in 35°C and 40°C n-hexane for 6 h, respectively. The interdiffusion coefficients of the binder and solvent are 9.763×10-7 cm2/s and 1.295×10-6 cm2/s, respectively. The temperature dependent interdiffusion coefficient for the Fe–6Ni–4Cu compact can be expressed as D x =4.534×10exp (-5437.2/T). The distribution of pore size is about 0.1–1.9 µm for the Fe–6Ni–4Cu compact.

The various processes for removing hydroxyl (–OH) absorption bands of Li2O–CaO–Al2O3–GeO2 (LCAG) glass and variables such as melting time, temperature, pressure, additive agent and heat treatment have been studied. The absorption coefficient (B OH) increases with increasing melting pressure, but decreases with increasing melting time and temperature. With added CaF2, the –OH group content in the glass may be decreased to B OH=0.068 mm-1. Since the test specimen is heat-treated at 630° C for 24 h, the O–H bond band shifts from 2.83 µ m to 2.99 µ m and bands at 3.37 µ m form due to the Ge–O bond.