The twist compression test (TCT) was designed and built at the University of Waterloo to measure the coefficient of friction between the sample of interest and tools used. An axial hydraulic cylinder provides up to 110kN (25kip) of normal load. Based on the annular contact area of the tool, the maximum interfacial pressure is 496MPa (72ksi). A hydraulic motor is used to rotate the tool at a maximum torque and speed (variable) of 1000Nm and 60RPM respectively. Data acquisition is done through a desktop PC with an in-house custom LabVIEW program. The data acquisition system measures the load from the transmitted torque and computes the coefficient of friction (COF) as a function of contact pressure and angle of rotation.
University of Waterloo twist compression apparatus