Weak Magnetic Detection System Of Ni-Cu Alloy Tube/Rod

Ni-Cu alloy has good room temperature mechanical properties and high temperature strength.It is commonly used to manufacture TWT and other electron tubes,and also can be used as structural materials of aircraft engines.Because Ni-Cu alloy is a non ferromagnetic material,its defect detection method is limited.This paper develops an automatic detection system for Ni-Cu alloy tube / bar based on flux weakening detection technology,which can greatly improve the online detection efficiency of Ni-Cu alloy bar and tube.First of all,in order to meet the requirements of automatic detection of Ni-Cu alloy tube / bar,combined with the measurement characteristics of fluxgate sensor,the overall design and implementation method of the system were determined,and the hardware detection platform was made.Secondly,encountered problems in the data processing,the three aspects of judgment,defect signals from defect imaging and quantitative methods are put forward to the corresponding data:(1)according to the shortage of existing defect probability discriminant method,proposed method of judging defect probability judgment don’t cycle based on the increased sensitivity to small signal defects;(2)put forward the defect type automatic recognition and image analysis method of feature extraction method based on the detection results more intuitive,more can restore the original appearance of defects;(3)the defect quantitative statistical analysis based on regression method.The topic takes the peak value of defect signal as the characteristic quantity,and applies regression statistics knowledge to fit the relation curve between the peak value and the defect depth of the defect signal,and uses this curve to quantify the defects of the same type and material workpiece.Thirdly,based on the research results in this paper,the on-line detection software of nickel copper alloy tube / bar is compiled by using C# language,and real-time data acquisition,processing,imaging and quantitative data are realized.Finally the use of the platform for the calibration of the defects with hole,groove of the Ni-Cu alloy bars,and the Ni-Cu alloy bar for the actual testing,including a display platform to detect internal defects of bar,and then through the defect through metallographic microscope analysis,verify the Ni-Cu alloy tube / weak magnetic bar feasibility online detection platform.The experimental results show that the Ni-Cu alloy tube / rod weak magnetic detection system can effectively detect the defects at the same time,the research on the nickel copper alloy tube / rod quality testing provides a new thinking and a new method for nickel copper alloy tube / rod engineering application lay the foundation for on line detection.