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为提高TiC/316L不锈钢复合材料的致密度和力学性能,采用温压成型和微波烧结复合方法制备了质量百分数为5%的TiC/316L复合材料.在MM-200型环块磨损试验机上研究了复合材料在干摩擦条件下的摩擦磨损性能,并与传统粉末冶金法制备的复合材料耐磨性能进行了对比研究.结果表明:与传统粉末冶金法相比,在相同的烧结温度下,采用温压成型和微波烧结制备的TiC/316L复合材料虽然内部也存在一些孔隙,但组织比较均匀,烧结比较充分,复合材料的致密度和耐磨性均得以提高.随着温压压制压力的增加,复合材料的相对密度和耐磨性快速增加,但过高的压制压力不利于耐磨性的提高.摩擦磨损试验结果表明在压制压力为400 MPa时,复合材料的耐磨性较好. 相似文献
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Ultrafast proton transfer dynamics of 2-(2'-hydroxyphenyl)benzoxazole dye in different solvents 下载免费PDF全文
The excited-state intramolecular proton transfer of 2-(2-hydroxyphenyl)benzoxazole dye in different solvents is investigated using ultrafast femtosecond transient absorption spectroscopy combined with quantum chemical calculations.Conformational conversion from the syn-enol configuration to the keto configuration is proposed as the mechanism of excited-state intramolecular proton transfer.The duration of excited-state intramolecular proton transfer is measured to range from 50 fs to 200 fs in different solvents.This time is strongly dependent on the calculated energy gap between the N-S;and T-S;structures in the S;state.Along the proton transfer reaction coordinate,the vibrational relaxation process on the S;state potential surface is observed.The duration of the vibrational relaxation process is determined to be from8.7 ps to 35 ps dependent on the excess vibrational energy. 相似文献
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