Investigation on the arc erosion performance of Ag–Ta_(2)AlCcomposite under air conditions

The Ta_(2)AlC material is designed to enhance the performance of Ag-based electrical contact materials as areinforcement phase.With a work function of 6.7192 eV,Ta_(2)AlC demonstrated significantly higher values thanreinforcement phase materials such as SnO_(2),ZrO_(2),and the commonly used MAX phase materials.Consequently,the arcerosion performance of an Ag–Ta_(2)AlC composite was investigated under air conditions.Gas breakdown mainly occurreddue to electron avalanches,with the observation of a streamer breakdown mechanism in a strongly nonuniform field.Thearc exhibited concentrated erosion on the surface of the Ag–20 vol%Ta_(2)AlC material,resulting in a higher arc energy.Asthe volume fraction of the Ta_(2)AlC material increased to 30%and 40%,the eroded area became more dispersed.Inparticular,Ag–30 vol%Ta_(2)AlC displayed the lowest arc energy(3.395 kJ)and shortest arcing time(33.26 ms).Among thefour tested components,the Ag–30 vol%Ta_(2)AlC composite demonstrated superior arc erosion resistance.Oxides of Ag_(2)O,AgO,Ta_(2)O_(5),and Al_(2)O_(3)were formed through the interaction of ionized Ag and Ta_(2)AlC particles.By combining theelectromagnetic force and plasma flow force,sputtered particles and bulges were generated on the eroded surface.Theseresearch findings contribute to broadening the applications of Ag–MAX materials in the realm of electrical contacts.