The Auxiliary Devices Of A Method For Measuring Residual Stress In Ferromagnetic Materials Based On The Changing Of Magnetism, Signal Producer And Data Analyzer

In many fields of the development of our country's economy .the apllication of ferromagnetism material is very abroad ,such as railroad ,oil pipe and other kinds of structure iron. The safty of these devices is very important to the work of National economy and the safty of people. The damage of ferromagnetism material is composed of three ordinary stages ,the convergence of stress ,the crevice,the rupture. So ,the monitor of the ferromagnetism material is the key to the safy of the whole device. The remain stress is the stress with balance state in the object on which no extern stress imposes .In the making process of many kinds of mechanism and machine ,the ramain stress will engender inside the accessaries .In fact ,the remain stress is impossible to avoid in the process of the accessaries .all kinds of remain stress will engender in the machining such as plus ,hustle ,roll, proofread,cutting,chop,hammer and heat machining .In the process of using ,the piled stress of the extern stress and the remain stress will make the stucture deformed and the redistributor of the remain stress ,then shorten the period of the normal use of the device, even bring grave accident. So the monitor of the remain stress is very significant. The research of detection to the remain stress origined from 1930s. now there are several decades methods which can be seprerated to two kinds : mechanical detection and physical detection , or can be called damnification detection and non damnification detection .The theory of mechanical detection is to release the part on which the remain stress impose by using certaian methods which is to separate or divide this section in part, and by measuring the distortion ,get the the value of the remain stress in flexibility mechanics. The benefit of this kind of method have higher reliability and veracity ,but its cost is to break the the structure more or less ,so in fact ,the applicaton si limited. Physical...