Abstract :
The magnetic properties of the YbFe4Al8 antiferromagnetic (TN=102 K) compound are reported in wide temperature and magnetic field ranges. The pronounced diamagnetic signal of the dc susceptibility has been discovered for this compound below T<50 K when the sample was cooled and measured in an applied magnetic field lower than H<500 Oe. The results obtained indicate that this magnetically active compound probably belongs to a new class of superconductors of the RFe4Al8 type structure. The estimated volume fraction of the superconducting phase was not higher than 15% in the studied sample.