Self-field quench behaviour of YBa₂Cu₃O _7-δ coated conductors with different stabilizers

Self-field quench behaviours of YBa₂Cu₃O _7-δ coated conductors with different stabilizers are studied. Samples include one with Cu on both sides (Cu-Cu), one with stainless steel on both sides (SS-SS), and one with Cu on one side and stainless steel on the other (Cu-SS). The measurements of the minimum quench energy (MQE) and normal zone propagation velocity (NZPV) are taken at various temperatures (30-75K), and transport currents (30% I_c to 90% I_c) at a typical pressure of 10^-5Pa. Of the three samples, the Cu-Cu sample has the highest MQE while the SS-SS one has the lowest MQE at the same temperature and percentage of I_c; the NZPV in the SS-SS sample is found to be the highest while those of the Cu-Cu and Cu-SS samples are similar. The normal zone voltage and the hot-spot temperature are also compared. Both the classic adiabatic quench propagation model and the interface resistance model are used to explain the NZPV and MQE differences between the samples. The implications for conductor design and quench detection and protection are discussed.