Research On Spheroidization Rate Audio Excitation Analysis And Detection

With the development of society,people's requirements for "security" are increasing.As a more and more widely used metal material,spheroidal graphite cast iron has better mechanical properties such as strength,toughness,hardness,and plasticity than other cast irons,and its comprehensive properties are close to steel.Spheroidal graphite cast iron is applied to the project when the quality is not up to standard,which has a potential threat to the operation of the company and the safety of people's lives.An important factor affecting the quality of spheroidal graphite cast iron is the shape and distribution of graphite molecules inside it,that is,the spheroidization rate.Therefore,it is of great significance to improve the detection level of spheroidization rate.With the continuous improvement of detection methods and analysis methods,the detection method of spheroidization rate has also been updated.At present,nodularity detection methods include metallographic method,Bezier contour fitting method,thermal analysis method,and ultrasonic detection method.In order to realize the spheroidal graphite cast iron spheroidization rate on-line detection and avoid errors caused by the detection principle,a spheroidization rate detection method is proposed by this paper based on audio excitation analysis.NO.1.The important characterization of the spheroidization ratio is the elastic modulus,and the elastic modulus has a significant effect on the natural frequencies of each order of the part to be tested.relationship.NO.2.ANSYS finite element simulation to simulate the first 9 order modal shapes of the spheroidal graphite cast iron DUT is used by this paper,analyzes the influence of the elastic modulus and mass on the natural frequency of each order,and compensates for the frequency change caused by the mass difference.NO.3.With MATALB as the main control platform,by controlling the on-off of the USBcontrolled relays,the device under test is stimulated.At the same time,the vibration pickup is controlled to collect and analyze audio,including windowing,zero padding,FFT,and denoising filtering.NO.4.In the selection of excitation points,a finite element exciting position optimization method is proposed,which combines the characteristics of each order mode,natural frequency,and modal excitation theory to select optimized exciting position to effectively extract the modal frequencies of interest and resolve adjacent The modal frequency provides a new theoretical basis for the selection of exciting position for online detection of audio spheroidization rate detection.The analogy is analyzed by this paper based on the big data obtained through experiments and the finite element simulation analysis data,and proposes a spheroidization rate difference evaluation algorithm,which can accurately assess the spheroidization rate based on the calibration results.The test results show that the audio spheroidization rate detection method is fast,suitable for the full inspection needs of the casting industry,and has good repeatability.