Cavitation erosion behaviour of niobium

► We studied the niobium cavitation erosion behaviour. ► Niobium samples in the cold-worked state have smaller cavitation-erosion resistance than the same material in the annealed condition. ► Cavitation-erosion failure mechanism in niobium occurs in a sequence of events comprising the fracture of debris allied to the effect of fatigue and microcracks formation. ► Annealed niobium presents similar incubation period but a worse behaviour in the maximum erosion rate stage, when confronted to the ASTM CA-6NM martensitic stainless steel results.