In order to obtain the evolution law of contact pressure between blank and tool interfaces in sheet metal forming, the numerical simulation model of a channel forming process was developed based on the finite element software ABAQUS. It was found from the numerical calculation that the contact pressure is comprised of an initial transient response and a steady phase in the duration of the forming process. While the contact pressure is continuous in steadystate and can be divided into a high contact pressure zone and a low contact pressure zone, the contact pressure in transient phase is discontinuous and is characterized by a twopeak contact pressure. The numerical results show the peak contact pressure in transient phase is much higher than that in steady phase, and the contact pressure on the blank at the start of die radius is higher than that at the end in steady phase. Furthermore, a parametric study was conducted. It was found that the steel strength has a positive proportion effect on the contact pressure, and the contact area increases with the increasing of the blank holder force.

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