【作者】 曾勇；

【导师】 徐宏； 侯峰；

【作者基本信息】 华东理工大学 ， 化工过程机械， 2010， 硕士

【摘要】 传统的火焰喷涂型金属多孔层的孔隙率较低,为了提高孔隙率,本文对火焰喷涂工艺参数进行优化,开发了不添加造孔剂直接喷涂铁基复合粉末制备金属表面多孔层的技术,实验研究了合金粉末组分、火焰温度和喷涂距离等工艺参数对表面多孔层的影响,进一步改进了火焰喷涂制造金属表面多孔层的工艺。测试了火焰喷涂型表面多孔层的孔隙率、当量孔径和结合强度；采用去离水和酒精作沸腾传热工质,实验对比研究了不同特征参数的火焰喷涂型表面多孔层对沸腾传热的强化效果。结果表明,本文所研制的火焰喷涂型表面多孔层的平均孔隙率高达64.5%,沸腾传热系数为光滑表面的3-14倍,并且涂层结合强度可以满足工业化应用要求。所得到的相关研究结果为火焰喷涂型表面多孔传热元件的开发与应用具有指导意义。更多还原

【Abstract】 The porosity of the traditional flame-sprayed porous surface coating is very small. In order to improve the porosity, this paper optimized the parameters of the flame spraying process and developed the technology of manufacturing the metallic porous surface coating by spraying directly iron-based composite powder without pore-forming materials. Moreover, this paper experimentally studied the impacts of process parameters on porous surface coating, such as the content of alloy powder, flame temperature and spraying distance, consequently further improved the flame spraying process of manufacturing the metallic porous surface coating. Besides, this paper tested the porosity, equivalent pore size and bonding strength of the porous surface coatings. Using water and alcohol as working fluid, this paper did experimental comparative study of the boiling heat transfer enhancement performances of the flame-sprayed porous surface coatings with different characteristic parameters. The results show that to the developed flame-sprayed porous surface coating, the average porosity is up to 64.5%, the boiling heat transfer coefficient is 3 - 14 times as large as that of the smooth surface, and the bonding strength could meet industrial application requirements. The relevant study results which have been obtained in this paper are instructive for the development and application of the heat transfer component with flame-sprayed porous surface coating.更多还原