To improve performance of PTFE-based damping material,composites with several fillers were prepared by compressing and sintering. The dynamic mechanical properties of the composites were investigated by means of visco...To improve performance of PTFE-based damping material,composites with several fillers were prepared by compressing and sintering. The dynamic mechanical properties of the composites were investigated by means of viscoanalyser. Temperature-dependent loss factors,storage modulus and loss modulus were obtained. And SEM was employed to study the compatibility between PTFE and fillers. The results show that,when blending PPS and PEEK at proper content,the loss factor curve appears double peaks,which can widen the high-damping temperature region of the composites. Blending graphite or alumina can increase the storage modulus obviously,but decrease the value of loss factor. And because graphite or alumina combines with matrix poorly,glide would happen at interface when bearing external load. The interface friction can dissipate vibration energy,which increases the loss modulus of the composites. Blending PPS,PEEK and graphite or alumina at right content,PTFE-based composites can meet demands as damping material in practical engineering.展开更多
This study fabricated textures on the stator surface of a traveling wave ultrasonic motor(USM)using laser and investigated the tribological behavior of a polytetrafluoroethylene(PTFE)composite friction material and st...This study fabricated textures on the stator surface of a traveling wave ultrasonic motor(USM)using laser and investigated the tribological behavior of a polytetrafluoroethylene(PTFE)composite friction material and stator.Initially,the effect of textures with different densities was tested.As the results suggested,the generation of large transfer films of PTFE composite was prevented by laser surface texturing,and adhesive wear reduced notably despite the insignificant decrease in load capacity and efficiency.Next,the 100-h test was performed to further study the effects of texture.Worn surface and wear debris were observed to discuss wear mechanisms.After 100 h,the form of wear debris changed into particles.The wear mechanisms of friction material sliding against the textured stator were small size fatigue and slight abrasive wear.The wear height of friction material decreased from 3.8μm to 1.1μm.This research provides a method to reduce the wear of friction materials used in travelling wave USMs.展开更多
基金the National Natural Science Foundation of China (Grant No. 50575054)the Science and Technology Tackle Key Problem Plan Foun-dation of Harbin, China (Grant No. 2004AA2CG126).
文摘To improve performance of PTFE-based damping material,composites with several fillers were prepared by compressing and sintering. The dynamic mechanical properties of the composites were investigated by means of viscoanalyser. Temperature-dependent loss factors,storage modulus and loss modulus were obtained. And SEM was employed to study the compatibility between PTFE and fillers. The results show that,when blending PPS and PEEK at proper content,the loss factor curve appears double peaks,which can widen the high-damping temperature region of the composites. Blending graphite or alumina can increase the storage modulus obviously,but decrease the value of loss factor. And because graphite or alumina combines with matrix poorly,glide would happen at interface when bearing external load. The interface friction can dissipate vibration energy,which increases the loss modulus of the composites. Blending PPS,PEEK and graphite or alumina at right content,PTFE-based composites can meet demands as damping material in practical engineering.
基金Natural Science Foundation of Zhejiang Province(No.LQ18E050002)Natural Science Foundation of Ningbo(No.2017A610076)Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms(No.BZ0388201702)for providing research funds and this study was sponsored by K.C.Wong Magna Fund in Ningbo University.
文摘This study fabricated textures on the stator surface of a traveling wave ultrasonic motor(USM)using laser and investigated the tribological behavior of a polytetrafluoroethylene(PTFE)composite friction material and stator.Initially,the effect of textures with different densities was tested.As the results suggested,the generation of large transfer films of PTFE composite was prevented by laser surface texturing,and adhesive wear reduced notably despite the insignificant decrease in load capacity and efficiency.Next,the 100-h test was performed to further study the effects of texture.Worn surface and wear debris were observed to discuss wear mechanisms.After 100 h,the form of wear debris changed into particles.The wear mechanisms of friction material sliding against the textured stator were small size fatigue and slight abrasive wear.The wear height of friction material decreased from 3.8μm to 1.1μm.This research provides a method to reduce the wear of friction materials used in travelling wave USMs.
