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Summary: A solid lubricant composite material was prepared by compression molding PTFE and acid treated nano‐attapulgite. The friction and wear tests were performed on a block‐on‐ring wear tester. Scanning electron microscopy (SEM), energy‐dispersive X‐ray spectrometer (EDS) and DSC were utilized to investigate material microstructures and examine modes of failure. Experimental results showed that there was no significant change in coefficient of friction, but the wear rate of the PTFE composite was orders of magnitude less than that of pure PTFE. Acid treated nano‐attapulgite was superior to untreated nano‐attapulgite in enhancing the wear resistance of PTFE. Moreover, the wear resistance of the composite increased monotonically with increasing treated attapulgite concentration. Investigation of transfer film and analysis of debris for PTFE and its composite showed that acid treated nano‐attapulgite filled to PTFE could facilitate formation of transfer film on the steel ring surface and inhibit breakage of PTFE molecular chain. The PTFE composite with higher heat absorption capacity exhibited improved wear resistance. Furthermore, the steel ring counterface abrasion was not found.
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简述了我国塑料助剂生产现状、市场供需及发展方向,“十五”期间我国塑料助剂工业发展势头强劲,目前已基本满足我国塑料工业的发展需求,但是在品种和产品质量等方面与国外先进水平相比仍有较大的差距。提出了提高我国塑料助剂国际市场竞争力的措施。 相似文献
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Jun-Hai Lv Mei Zhang Min Guo Wen-Chao Li Xi-Dong Wang 《International Journal of Applied Ceramic Technology》2007,4(6):571-577
NaNbO3 , KNbO3 , and K x Na(1− x ) NbO3 powders were successfully prepared by the hydrothermal method. The phase of the products was identified to be orthorhombic structure by X-ray diffraction (XRD) technique, and the XRD results revealed that the x value of the K x Na(1− x ) NbO3 gradually increased with the increase in the ratio of K+ to Na+ in alkaline solution. The morphology and the microstructure were investigated by scanning electron microscopy, energy-dispersive spectroscopy, and transmission electron microscopy, and the results indicated that the ratio of K+ to Na+ in the solution had a great effect on the morphology and the size of products. Na0.5 K0.5 NbO3 with morphotropic phase boundary composition could be synthesized when the molar ratio of K+ to Na+ was between 4:1 and 6:1 in the solution. A possible formation mechanism of the K x Na(1− x ) NbO3 crystal was also proposed based on the experimental results. 相似文献
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