The process of a Bi-2223/Ag ribbon sintering studied by the method of acoustic emission

The secondary sintering of a Bi-2223/Ag ribbon, following the stages of primary sintering and rolling to a strain of ε ∼ 18%, was studied by methods based on the acoustic emission, thermal expansion, and magnetic susceptibility measurements. During the second thermal treatment, a signal of acoustic emission from the ribbon was detected in a temperature range from 570 to 660°C. The process of liquid-phase healing of the rolling cracks in the ribbon material is considered as a reason of the acoustic emission. The possibility of using the acoustic emission measurements for nondestructive testing in the Bi-2223/Ag ribbon fabrication technology is considered.