Metal magnetic bomb, magnetic memory signal acquisition and processing system research
|School||Beijing University of Chemical Technology|
|Course||Detection Technology and Automation|
|Keywords||Non-destructive testing Ferromagnetic materials Magnetic bomb Magnetic Memory The digital filter|
Ferromagnetic material has good elastic and plastic , and has a hard , corrosion , etc., is widely used at present and in the future industrial materials and can not be replaced . In industrial production , machining of parts made ??of ferromagnetic material and composition of the product , in the course of quality problems , damage issues and end of life , not only to the normal operation of the product , or even related to personal safety. Thus , various properties of the ferromagnetic material , such as stress , hardness, fatigue, and other aspects of test has important significance. With the development of modern industry , the ferromagnetic material components for stress detection has become to ensure safe operation of equipment as well as an important means of product quality . Relative to other common stress detection methods, elastic and magnetic metal magnetic memory testing methods in recent years to develop two more advanced NDT techniques . They are the internal stress in the detection of ferromagnetic materials , fatigue life , hardness , microstructure, surface state all have their own advantages, products or equipment can conduct an overall analysis, evaluation , development potential is very dynamic NDT methods . In this paper, elastic and magnetic metal magnetic memory signal generation mechanism and various properties of ferromagnetic materials conducted in-depth and meticulous research . And on this basis , developed based on metal magnetic memory technology magnetic shells and ferromagnetic material stress testing instruments. The instrument includes sensors, signal conditioning circuits, and MCUs three parts. For the magneto-elastic metal detector high-frequency interference signals appearing proposed selection field programmable logic device (FPGA) to implement low-pass digital filter to filter high frequency noise. Further be described using VHDL language , and simulation verification, simultaneously applied magnetic bombs online testing, to achieve a higher accuracy.