一、前 言 镁合金MB15型材是我国目前广泛使用的飞机受力构件。 多年来由于采用二次挤压的生产工艺,型材的截面上存在有不同程度的粗晶组织。机械性能显著降低。如拉伸强度为28～32公斤/毫米~2,达不到冶标YB632-66强度指标的要求(σ_b≥32公斤/毫米~2)。而且由于型材塑性低,工艺成型时产生裂纹而引起报废。 First, the preface Magnesium alloy MB15 profile is currently widely used in China’s aircraft force components. Over the years due to the use of secondary extrusion production process, there are sections of the profile of different degrees of coarse grain structure. Mechanical properties are significantly reduced. Such as the tensile strength of 28 ~ 32 kg / mm ~ 2, not up to the standard YB632-66 strength index requirements (σ_b ≥ 32 kg / mm ~ 2). And because of low profile plastic, crazing process generated when scrapped.