Analysis of friction in warm and hot forging

  • Bay, Niels Oluf (Project Manager)
  • Wanheim, Tarras (Project Participant)
  • Post-Pedersen, Bente (Project Participant)
  • Eriksen, Morten (Project Participant)

    Project Details

    Description

    Ph.D.: Bente Post-Pedersen
    The Ph.D.-project is a part of the national funded MUP2 Center: Structural Materials, Materials Processing, Properties and Modelling, MP2M-centre.
    The aim of the Ph.D.-project is development of a method to determine friction in hot and warm forging. The main work is concentrated on investigation of the influence of lubrication and temperature on the friction conditions during a hot forging process. The influence of workpiece temperature as well as the tool temperature is analysed. A tool for measuring surface temperature during the metal forming process has been developed.
    Determination of the friction has been carried out using a new compression-twist type friction test for testing friction in warm and hot forging. Applying a redesigned screw press, where the cross head guide has been demounted and a rotating tool is mounted directly on the end of the spindle the test can be carried out rapidly, performing the compression and the twist movements simultaneously. The speed of the test is essential to obtain useful results testing friction in warm and hot forging.
    The developed test has been verified under cold forging conditions. Friction and lubrication in cold forging of aluminium has been investigated. The experiments were carried out with various surface states: dry, pickled, lubricated with either oil or graphite, aluminate coated and lubricated either with oil, MoS2 or soap.
    The influence of the oxide layer, surface enlargement, tool temperature, workpiece temperature and workpiece material on the friction, are investigated by variation of the tool and workpiece temperatures.
    StatusFinished
    Effective start/end date01/01/199531/05/1998