In one embodiment a locking mechanism for a hinge, comprises a housing defining a chamber which is to contain a magnetorheological (MR) fluid, a bias mechanism which disposed at a first end of the chamber, a piston disposed at a second end of the chamber, the piston to be coupled to a hinge rotatable about a first axis, wherein rotation of the hinge about the first axis translates the piston laterally in the housing on a first side of the chamber, and a magnet positioned proximate the housing to change the MR fluid from a first state in which the MR fluid exhibits a low viscosity to a second state in which the MR exhibits a high viscosity. Other embodiments may be described.