Friction and wear behaviors of PI/UHMWPE blends using a high temperature reciprocating tests: effect

• 作 者: Song Chen Haitao Duan Lei Wei Bingxue Cheng Jian Li
• 机 构: State Key Laboratory of Special Surface Protection Materials and Application Technology, Wuhan Resea
• 出 处: 第十一届全国表面工程大会暨第八届全国青年表面工程学术会议
• 发表日期: 2016年4期
• 关键词: PI UHMWPE composites friction wear

　　In this work, polyimide (PI) and ultra-high molecular weight polyethylene (UHMWPE) were used to fabricate composites by hot-press molding. Maleic Anhydride grafted Low Density Polyethylene (MAH-g-LDPE) was added to enhance the compatibility between the phases of PI and UHMWPE. Considering the melt and degradation temperature of the polymers, the temperature of heat preservation in the fabrication process was selected between 310~380℃. The friction and wear behaviors of PI/UHMWPE at the environment temperature of 100℃ were investigated on a reciprocating ball-on-flat contact tribometer, the results show that friction coefficient of composites/GCr15 friction pair of composites decrease with the increasing of PI content when the mass fraction of PI is less than 50 wt%, and subsequently increase with PI proportion continue increasing. The wear rate of composites shows the same rules with friction coefficient. It is observed from the optical micrographs of wear scar on PI/UHMWPE surfaces after tests that the shape of wear scratches is in accordance with the GCr15 ball when the mass percent is less than 50 wt%, while the shape of wear scratches is irregular for composites with PI content more than 60 wt%. SEM images show that worn surfaces of composites with PI content between 30~50 wt% are smooth and clean as a mirror, indicating these samples have excellent wear resistance; worn surfaces of composites with PI content less than 30 wt% occur adhesive wear and fatigue micro-cracks appear on worn surfaces of composites with PI content more than 50 wt%. The ultimate objective of this study was trying to find a series of new composites which has good overall performance and excellent friction and wear properties at working environmental temperature beyond thermal deflection temperature of UHMWPE.