Brazing parameters and mechanical properties of silicon nitrides/stainless steel joint

Abstract

The present study investigates the effects of the brazing parameters, such as brazing temperature and time, on the fracture strength of Si3N4/stainless steel joint with Cu-interlayer. It was found that the thickness of the Cu-interlayer was decreased by the dissolution of Cu-interlayer into the brazing alloy with the increase of the brazing time or temperature. The Cu interlayer was dissolved completely into the brazing alloy for the joint brazed at 950°C for 10 min. Meanwhile, the thickness for the reaction product at the Si3N4/brazing alloy joint interface was increased with the increase of the brazing temperature and the holding time. The increase in the thickness of the reaction product with the brazing temperature was more rapid than the increase in the thickness of the reaction product with the brazing time. The increase in the thickness of the reaction product with the increase of the brazing temperature is responsible for the decrease in the fracture strength of the joint. The brazing temperature is considered to be a crucial factor in determining the joint fracture strength of the Si3N4/stainless steel joint with Cu-interlayer.