Abstract: A heat-transfer device and system for conducting heat from a heat source. The heat-transfer device can include an evaporator having one or more reinforcement elements occupying respective recesses defined in a body of the evaporator, wherein the reinforcement elements are more resistant to deformation under clamp load than the material of the evaporator body, while still having desirable heat conductivity. In some embodiments, the heat-transfer system includes a plurality of serially coupled evaporators for generating a respective vapor; at least one reinforcement element interposed between adjacent evaporators; and a condenser in fluid communication with the evaporator.