Creep behaviour of Ni-base single-crystal superalloys with various γ′ volume fraction

Creep tests at 900 °C, 392 MPa and 1100 °C, 137 MPa were performed on a third generation Ni-base single-crystal superalloy TMS-75 and its γ/γ′ tie line alloys. These tie line alloys were designed to contain various volume fractions of γ′, while the compositions of two individual phases were kept the same. The longest rupture life was attained by an alloy with γ′ content in vicinity of 65% in both creep condition, which is similar trend has been...