Studying On Chromatic Difference Of Mechanical Supercharger Non-dynamic Load Surface With Damage By Pulse TIG Welding Remanufacture Repairing

At present,the remanufacturing repair of the aluminum alloy casing of the supercharger ZL101 A is usually performed by pulsed TIG welding,wherein the color difference method is one of the methods for detecting the quality of the welding,but the method is only an observation of the macro surface defects of the weld.In view of this,this dissertation mainly studies the optimization of the pulsed TIG welding process parameters of ZL101 A aluminum alloy,the influence of microscopic surface topography on the surface chromaticity of ZL101 A aluminum alloy and the influence of pulsed TIG welding repair process parameters on weld chromaticity.It aims to quantify the color difference between the weld and the substrate after welding,analyze the relationship between the color difference and the welding quality,and provide a reference for the quality of the pulsed TIG welded aluminum alloy by using the color difference method.The research content of this dissertation is as follows:(1)The orthogonal design is used to optimize the process parameters of ZL101 A aluminum alloy pulse TIG welding: firstly,three parameters of welding current,cleaning current and cleaning time are selected for orthogonal design of three factors and four levels;The samples in the orthogonal design table are welded to the sample,and the tensile test is performed after welding.Finally,the tensile strength of the sample is analyzed by direct observation and range analysis,and the optimal parameters are obtained.Perform a validation analysis.(2)Study the effect of the surface profile state of ZL101 A aluminum alloy on its chromaticity: on the basis of manual grinding of the samples by W20(02),W10(04)and W7(05)metallographic sandpaper,the granularity is used in sequence.The W2.5 and W1.0 abrasive pastes were polished on a polishing machine to measure the roughness and chromaticity of each treated sample;the values between the grain size,roughness and color difference of the sandpaper or abrasive paste were compared and analyzed.The relationship between the sample processing mode and the chromaticity is obtained,and based on the result,support is provided for the processing method before the color measurement of the subsequent test sample.(3)Study the influence of process parameters of pulse TIG welding repair on weld chromaticity: compare the data of chromatic aberration and tensile strength of the sample after orthogonal design experiment,and obtain the relationship between the two and pass the second experiment.Verify the repeatability of the experiment;and analyze the cause of the chromatic aberration.