Abstract:A lignin fiber reinforced friction material was prepared,and its mechanical properties and tribological properties were investigated by using the impact tester and hardness meter,and the friction and wear tester,respectively.The morphology of the cross section and the worn surface of the friction materials were analyzed by Scanning Electron Microscope (SEM) and Xray diffractometer,and the wear mechanism of friction materials was investigated.The results show that,compared with steel fiber,the lignin fiber can improve the impact toughness and fracture toughness of friction materials,and reduce the hardness of friction materials.A layer of dense friction and transition film is formed by the lignin fiber on the surface of friction material during the friction process,so the lignin fiber reinforced friction material has stable friction coefficient,has no significant decrease of friction coefficient when the temperature is above 300 ℃,and its wear rate is within the provisions of national standard.The analysis results by SEM and Xray diffractometer show that lignin fiber has high combining strength with matrix,and has a obvious enhancement effect to friction materials.The main wear mechanisms of lignin fiber reinforced friction material are abrasive wear and fatigue abrasion at high temperature.