Measurement of local creep strain in the notch region using AC potential drop technique

In the present study, an attempt has been made to ascertain the capability of Alternating current potential drop (ACPD) technique to measure local creep strain in the notch region of specimens, which has an important technological significance in terms of monitoring creep damage in aeroengine components with intricate shapes. To this end creep strain measurements on both smooth and notched specimens of DSCM247 superalloy at 1050 °C and 125 MPa were carried out using linear variable differential transducers (LVDTs) as well as ACPD techniques and established that the creep strain measured by ACPD technique corresponds to the strain accumulated in the notch region. This was further substantiated by direct measurement of creep strain in the notch region by using non-contact laser gauging system.