Investigation of Metal Magnetic Memory for Stress State Identification in Steel Components

传统的磁检测技术需要将磁化磁通直接施加到铁磁部件上，以**从缺陷产生漏磁(MFL)信号或用于检测应力。将这种技术应用于**检查大量材料既耗时又昂贵。磁化技术在**检查不规则结构的情况下也受到限制。金属磁记忆(MMM)方法是一种潜在的替代检测技术，可用于识别钢构件的应力。例如，它可以用于应力集中在**坑附近、局部塑性变形、或由于地面沉降或滑动而产生的管道中。诱导应力产生的条件可能导致**应力腐蚀开裂。MMM是一种被动技术，它使用地球磁场的磁化**与其他潜在因素相结合来评估部件的应力状态。MMM是基于磁弹性(维拉里效应)的。这是一种快速**扩展的方法，用于检测由于应力状态的局部**变化而导致的表面或铁磁部件附近的磁场异常。MMM可以用来从地面确定管道的位置，并有可能利用廉价的磁传感器阵列来评估**管道的应力状态。改进的技术加上对**MMM物理基础的更好理解，可以带来简单的监测能力，从而提高**基础设施的使用寿命和性能，如水/废水和天然气/石油管道、涡轮机、压力容器、钢轨、焊接和铸件。

Conventional magnetic inspection technologies require direct application of magnetizing flux to ferromagnetic components to**generate magnetic flux leakage (MFL) signals from defects or for the detection of stress. Applications of such technologies to the**inspection of large volumes of material are time consuming and costly. Magnetization techniques are also limited in the case of**inspection of irregular structures. Metal magnetic memory (MMM) method is a potential alternative inspection technology that may**be used to identify stress in steel components. For example, it can be used in pipelines, where stress concentrations arise near**pits, localized plastic deformation, or due to ground settling or slippage. The induced stresses produce conditions that may lead to**stress corrosion cracking. MMM is a passive technique that uses the magnetization of the earth's magnetic field in combination**with other potential factors to assess the stress state of the part. MMM is based on magnetoelasticity (Villari effect). It is a rapidly**expanding method for the detection of anomalies in magnetic fields at the surface or near ferromagnetic components due to local**changes in their stress state. MMM can be used to determine the location of pipe from above ground and has potential to assess**the stress state of pipe utilizing inexpensive magnetic sensor arrays. Improved technology coupled with a better understanding of**the physical basis of MMM could lead to simple monitoring capabilities and, hence, improved service life and performance of**infrastructures such as water/wastewater and gas/oil pipelines, turbines, pressure vessels, rails, welded and casting parts.**