<p>Due to the corrugated micro-channels and extremely thin-walled structure of bipolar plate, damage and crack probably occur and accumulate rapidly during the forming process in case of inappropriate loading, thereby increasing the risk of failure in service. Yet, few studies focus on the relations between loading states and forming failures of bipolar plates. As a result, deformation damage and crack propagation of TA1 titanium alloy bipolar plates in three typical loading states, corresponding to rubber forming, hydroforming, and stamping, respectively, were comparatively studied in this work. The results showed that micro-channels formed by rubber forming exhibited larger forming depth, critical strain, and flow area compared with those formed by hydroforming and stamping. It could be attributed to the increased metal inflow towards die cavity, which was induced by the adhesive force generated by rubber at rubber/sheet metal interface. By using rubber with moderate Shore hardness (around 43 HA) as the pressure-carrying medium, stress triaxiality and the tolerance of accumulative damage in critical state (i.e., before fracture) were increased dramatically. This can be attributed to the more uniform distribution of normal pressure and metal flow velocity. Meanwhile, by introducing failure criteria in numerical calculation, fracture behaviors were analyzed together with microscopic observation. It was inferred that crack propagated more slowly as rubber’s Shore hardness decreased. Meanwhile, when using rubber with moderate Shore hardness, smaller crack length on the surface of bipolar plate and relatively larger density of dimples on the fractured surface were observed, which proved the occurrence of obvious ductile fracture.</p> Graphical Abstract <p></p>