Study on Tensile Magnetic Memory Characteristics of Demagnetization 16Mn and Q235 Steel

摘要

Tensile tests were carried out on demagnetization 16Mn and Q235 steel samples at loading state, and the magnetic memory characteristics were analyzed. Experimental results show the mean magnetic field intensity (MMFI) of a measuring point is more effective than that of other measuring points at the same stage to study tensile magnetic memory characteristics of demagnetization 16Mn and Q235 steel samples. At the elastic deformation stage, the MMFI of the measuring points at one fracture side increases while it decreases on the other fracture side. The MMFI decreases with the distance from the fracture location, and the change rate of the MMFI is almost equal. The variation law shows changes of opposite direction. At the strengthening phase, the relation between MMFI and tensile displacement is similar with that of the plastic deformation stage, but the variation amplitude was accelerated obviously. Comparison of 16Mn and Q235 steel shows that the standard deviation variation of the magnetic field intensity with the tensile displacement increases as the tensile strength of materials increases. For the demagnetization bearing components, weak areas can be estimated according to breaking laws, so more monitoring points can be set. Pre-breaks could be found through the appearance of inflection point of the MMFI of monitoring point. The inflection point of the mean curve is the breakpoint.