Microstructure and Properties of a Glass-Fiber Composite as a Function of the Specific Surface Area of the Lead Titanate Filler

Abstract

Influence of the specific surface area and filler concentration on the coefficient of linear thermal expansion (CLTE) of sintered composites based on high lead fused glass and lead titanate was investigated in order to obtain solder materials offering unusually low CLTE values. The microstructure of compositions was investigated by optical microscopy methods in combination with birefringence testing with a localization of about 1 μm. In samples containing up to 55% PbTiO₃ powder having a specific surface area of less than 560 cm²/g, near-zero and even negative values have been achieved.