The effect of firing temperature and firing time on the phase composition, microstructure, biaxial flexural strength, and temperature coefficient of expansion (TCE) of the popular low-temperature co-fired ceramic (LTCC) material was presented. In the studied materiali which is a composite of lead borosilicate glass and alumina particles at temperatures around 700°C the Al2O3 starts to dissolve in a low viscosity glass phase and this takes place up to 800°C, when 10 wt% of Al2O3 ceramic filler is dissolved in the glass phase forming the alumina-enriched area. This area is suitable for the crystallization of anorthite, which nucleates on the Al2O3 particles. The crystallization starts at 875°C and the mass fraction of anorthite increases with increasing temperature until it reaches a plateau value of around 22 wt% at higher temperatures or longer firing times. The major effect on the biaxial flexural strength of LTCC is that of porosity. The effect of the amount of anorthite on the LTCC biaxial flexural strength is minor. The TCE is correlated with the anorthite mass fraction, which crystallizes at the expense of a decreasing amount of glass phase in the LTCC.
COBISS.SI-ID: 26548263
In this work the effect of the firing temperature of DuPont 951 LTCC material, fired between 800 °C and 1000 °C, on the elastic modulus, the mechanical strength and the fracture toughness, was studied. The phase composition, mainly given by different ratios of the alumina, anorthite and glass phases, had a negligible effect on the strength of LTCC. The lower elastical modul (20%) and lower flexural strength of the LTCC could be correlated to the relatively high porosity of the samples sintered at lower temperatures.
COBISS.SI-ID: 26700583
In the paper the design of LTCC (low-temperature cofired ceramics) structure for combustor for the use in chemical microreactor was presented. Additional attention has been paid to thermal management. The combustor consists of inlets for fuel and air, the evaporator of the fuel, the fuel-air mixer, eight micro-burners, and the exhaust system. Electrical heater is integrated to start-up the system, and temperature sensor is integrated for temperature monitoring.
COBISS.SI-ID: 26785575