PdAgCu ternary alloy membranes were synthesized by the sequential electroless plating of Pd following by electroplating of Ag and Cu onto stainless steel substrate. The composition of the composite was varied by changing the deposition times. The fabricated layers were annealed at the temperatures between 500 and 600 degrees C for 20-60 h. The Energy Dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) were employed to investigate the element distribution in the membrane which provided the insight on membrane alloying process. Complete formation of the alloy could be obtained when the Pd composition was greater than a critical value of 60 wt%, and Ag and Cu contents were in the range of 18-30 wt% and 2-13 wt%, respectively. Deposition times of Ag and Cu were found to affect the completion of alloy formation. Excess amount of the deposited Cu particularly tended to segregate on the surface of the membrane. (C) 2016 Elsevier B.V. All rights reserved.