| With the continuously develop and progress of society, people pay more attention to rational utilization of resource and high effectively comprehensive utilization of energy sources.According to the fact that the superior function of heat pipe and rich aluminum content, this essay exploited and researched "Ω" type axial grooved aluminum heat pipe recycling the middle-low temperate waste heat which produced by the steel industry, the big energy consuming. Because of the limited corrosion resistance and the particularity of the service environment of the heat exchanger of aluminum material in this research, this research use the way modify the surface of high-efficiency aluminum heat tube buddle by electroless plating Ni-P alloy and improve the heat tube buddle corrosion resistance to meet the requirement that the temperature of exhaust gas emissions of heat treatment furnace will be reduced from300℃to150℃.to solve this problem. Due to the majority of energy burned in the steel industry are coal resource, so a large quantities of coal resource burned and produced many waste heat, and the waste heat contained a large amount of sulfurous corrosive gases and many dust particles. So improve the corrosive resistance efficiency of aluminum heat tube buddle is the key point of the research.This research expounded the process and method of surface treatment of aluminum and aluminum alloy and mainly researched the effects of the pretreatment process of electroless plating Ni-P alloy as well as the main salt, reducing agent, complexing agent, buffer, pH value of plating liquid and plating liquid temperature on Ni-P alloy electroless plating. And determined the pretreatment process of electroless plating Ni-P aluminum substrate and three sets basic craft formulas of electroless plating Ni-P alloy on aluminum substrate. Heat treat the plating pieces at180℃×2h、290℃×2h、350℃×2h、400℃×2h heat treatment technology, then study the binding force of the plating and the substrate of alloy discovered that after180℃×2h heat treatment can effectively improve the coating and substrate adhesion properties.And tested Na-Cl (3.5%) solution by polarization curve test discovered that the best corrosion resistant is Ni-13.79%P. And by soaking in the sulfuric acid solution weightlessness experiment shows, Ni-13.79%P soaked in10%sulfuric acid solution for three weeks (21d) weight loss the lest. Using the self-made simulated flue corrosion box test with the experimental conditions of temperature300℃, the volume fraction of SO2is1%, place210g dust particles in the furnace and use the motor drives the fan blowing dust particles, and then make experiment in simulated flue corrosion environment under the above conditions for10h, the types divided into the different phosphorus content plating pieces in plating condition and the plating pieces treated with different heat treatment. The results of the experiments show that type number13(Ni-13.79%P) have minimum weight loss after290℃×2h heat treatment.The final determined that the technology of electroless Ni-P alloy plating on aluminum heat pipe is:Model'machinery polish (polishing)'ultrasonic cleaning'alkalinity degreasing'acid pickling'zinc dipping'draws back zinc'secondary zinc dipping'electroless plating'drying'heat treatment'finished product. The electroless plating formula is:Nickel sulfate (NiSO4.6H2O)30g/L, sodium hypophosphite (NaH2PO2.H2O)25g/L, succinic acid (C4H6O4.6H2O)12g/L, hydroxy-succinic acid (C4H6O5)20g/L, compound additives3g/L, PH=5.3, temperature:90℃; The heat treatment technology is:200℃×2h. |
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