A Research For New Process Of Cuprobraze For Indoor Steel Radiator Of Combined Type Section Tube

In this thesis, it was briefly introduced that the status of domestic heating industry and products, the advantages and disadvantages of existing radiator were analyzed and compared in this research , as a result steel radiators were proved that they were in conformity with the existing provisions of《Code for design of heating ventilation and air conditioning》.They were dominant in energy saving and efficiency, low cost, beautiful and durable, environmental aspects. Therefore, the study of hard soldering process on the radiator had social and economic benefits.Firstly, the radiator heat transfer mechanism was analyzed and studied in this article, in order to develop new types of section tube steel radiator in accordance with the heat efficiency improving, then the structure was determined, in addition the radiating condition of section tube steel radiator and tubular radiator was simulated by FLUENT software. Through the comparison of temperature distribution, the distribution of turbulence, temperature field in the setting of the room and the velocity field of the two kinds of radiators single tube, these results demonstrated that section tube steel radiator had the better effect of heat dispelling. Then brazing mechanism for the 08 steel furnace brazing was analyzed and researched, eventually the ratio of each component material in copper solder paste, specimen preparation, connector type and process parameters were identified, finally the technology curve was formulated.In this paper, it carried out a large number of tests, such as, the test of wettability, the metallographic microstructure and shear strength of brazed joints, corrosion tests and X-ray diffraction study .Based on these tests, it proved that copper solder paste had a good wettability, and mechanical properties of brazed joints could reach the request. By observing microstructure of brazed joints and X-ray diffraction experiment, it could be determined that parts of a joint solid solution were in line with the ideals of brazed joint request of the organization. The optimum parameters of paste brazing copper brazing 08 steel was obtained through the experiments: joint clearance 0.03 ~0.05 mm ,brazing temperature 1100 ~ 1150℃, holding time 5 ~10min .Compared the performance of the copper solder paste with ordinary copper solder, it was found that the sputtering phenomenon did not happen when the copper solder paste was fluxing in the process of furnace brazing, however sputtering phenomenon was occurred by using the copper solder powder. After a certain period of time, it was observed that copper solder paste had no obvious stratification phenomenon; as a result copper solder paste was proved to have good performance of the operation process.CuproBraze technology of steel radiator belonged to the field of new technology, the results of theoretical studies and experimental research will play an important role in this area. In addition it will play an important theory foundation in promoting and facilitate automated production of indoor steel radiator.