GH536镍基高温合金焊接组织演变

发布时间：2018-04-23 15:02

  本文选题：GH + 镍基高温合金　； 参考：《航空材料学报》2015年06期

【摘要】：使用体视显微镜、光学显微镜、扫描电镜及其能谱仪对GH536焊接接头组织进行分析,结果表明:固溶态GH536由γ基体、大量M6C及少量M23C6组成;焊后,大量M6C在晶内弥散析出,在晶界和孪晶界上不连续析出,原有的碳化物长大。热影响区分为三个区域:靠近母材处,存在粗大"岛链状"碳化物;中部,部分碳化物重新固溶入基体,存在"网链状"碳化物;靠近熔合线,存在碳化物贫化区。焊缝处碳化物在晶界和枝晶间析出,从边缘到中心逐渐凝固:初始阶段,组织为非外延式生长的胞状晶,生长方向垂直于熔合线;中间阶段,组织转变为柱状树枝晶,且越靠近焊缝中心,晶粒尺寸越大;中心为粗大的等轴状树枝晶。焊接过程中,焊缝金属中各元素未损失。
[Abstract]:The microstructure of GH536 welded joints was analyzed by stereoscopic microscope, optical microscope, scanning electron microscope and energy dispersive spectrometer. The results show that the solid solution GH536 consists of 纬 matrix, a large amount of M6C and a small amount of M23C6, and after welding, a large amount of M6C is dispersed in the crystal. Discontinuous precipitation occurs at grain boundaries and twin boundaries, and the original carbides grow up. The thermal effect can be divided into three regions: near the base metal, there are coarse "island chain" carbides; in the middle, some carbides are re-dissolved into the matrix, and there are "network" carbides, and near the fusion line, there are carbides depleted areas. The carbides in the weld are precipitated between grain boundaries and dendrites, and solidified gradually from the edge to the center: in the initial stage, the microstructure is a non-epitaxial cellular crystal, the growth direction is perpendicular to the fusion line, and in the intermediate stage, the microstructure changes to a columnar dendrite. The bigger the grain size is, the bigger the equiaxed dendrite is. During the welding process, the elements in the weld metal are not lost.
【作者单位】： 北京航空材料研究院;中航工业失效分析中心;航空材料检测与评价北京市重点实验室;
【分类号】：TG407
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本文编号：1792455