Researchers have developed many passive damping devices to dissipate seismic energy using steel’s yielding property. Some proposed thick curved steel plates, while others proposed complex-shaped steel dampers. For instance, some have developed Shear Yielding Panel Devices (SYPD) and Triangular-plate Added Damping and Stiffness (TADAS) dampers for moment-resisting frames. However, these devices require additional steel bracings to be fitted into the structure. The present work reports an experimental study on a new energy dissipation device. The proposed damper is made of a steel plate cut into a curved shape (diaphragm), welded to flanges, and stiffened to create sub-panels. The damper can be fitted to the beam-column joints of steel structures using a bolted connection and does not need bracings; hence, it can be easily replaced after a seismic event. Eight devices were fabricated and tested under quasi-static cyclic loading protocol as per ATC 24. The results showed that all specimens exhibited hysteresis behavior, dissipated between 10 and 20 kJ of input energy, and provided a damping ratio of up to 40 %, depending on the damper’s geometry. Thus making it an effective seismic-resistant design system for new constructions and an alternative retrofitting tool for existing structures.