| In recent years, all kinds of machinery and equipment are going to the trend of high speed, more huge and more intelligent, the problems of vibration and noise of mechanical equipment are getting more and more attention of people. The effect of the vibration and noise is the reliability and stability of the mechanical equipment. It will lead to incorrect readings, reduce the life of equipment, and even happen major accidents such as car, aircraft and rocket crash. Even if it is a stable vibration source, it will also lead to vibration fatigue problem in the process of long-term and continuous vibration.What is more, it will reduce the using performance of mechanical equipment, shorten the service life of equipment, and the noise of vibration may cause serious damage to people’s physical and mental health. Therefore, by means of vibration and noise damping technology to improve the man-machine work environment has made it so imperative. Through early laboratory research suggests that NiCrAlY coating on stainless steel base can effectively strengthen the damping performance of the stainless steel base, it also has the effect of vibration and noise damping significantly. This paper will go a step further to expound spraying NiCrAlY coating on stainless steel substrate, then test the coating samples with vacuum annealing treatment. Through the analysis of micro structure, discussing the effect of different annealing temperature on the damping property o f N iCrAlY coating.First, NiCrAlY damping coating were prepared on the stainless steel substrates by arc ion plating machine. The coatings samples were prepared in a set of optimum process parameters. According to the properties of the material itself, the experiment adopts annealing experiment under the vacuum state. The seven groups of coating samples were sealed in3x10-3Pa vacuum quartz tube. Tube furnace was used to make the vacuum annealing experiment at different temperature respectively.Second, the microstructure of the samples will be tested by scanning electron microscope (SEM), energy spectrum analysis (EDS) and X-ray diffraction (XRD).Then we could get the morphology structure, component,phase structure of the coating samples. The effect on morphology structure, component,phase structure at different annealing temperature was studied.Through the discussion and analysis of the result, we could find the changing rule of the morphology, composition, structure, etc.Finally, DMA(Dynamic Mechanical Analyse) test was carried on the perpared samples and damping capacity was obtained. Under the condition of room temperature and variable temperature, three point bending method was applied to test the samples’storage modulus(E’) and loss modulus(E"), and the damping capacity of coating samples were obtained(Q-1). Through the study of microstructure of the coating, we could find the effect on the damping structure, reveal the influence of damping performance at different annealing temperature on the coating, and discusse the relationship between damping performance and the environment temperature, load frequency, the applied load.Results indicated that the coating samples’stacking fault, porosity and other factors could enhance the damping capacity. In order to achieve the best damping performance, it needs different annealing processing on the basis of different operating conditions. |
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