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本文选用镍基单晶高温合金，用籽晶法控制各晶粒的晶体取向，进行了多晶组合的竞争生长实验，模拟了定向凝固中不同晶体取向晶粒间的生长过程与竞争规律，结果表明：晶粒的竞争生长过程取决于晶粒的相对取向关系及其与热流方向的夹角，择优生长方向与热流方向最接近的晶粒将淘汰其它晶粒并逐渐占据整个试样截面；当两个晶粒的择优生长方向都与热流方向不平行且以大发散角方式组合时，两晶粒间可出现第三个晶粒并最终扩展至整个试样截面。
In this paper, nickel-based single crystal superalloy was selected, and the crystal orientation of each crystal grain was controlled by the seed crystal method. The competition experiment of polycrystalline combination was carried out to simulate the growth process and competition law between different crystal oriented grains in directional solidification. The results show that the competitive growth of the grains depends on the relative orientation of the grains and the angle between them and the direction of the heat flow. The grains with the best orientation in the direction of heat flow will eliminate other grains and gradually occupy the entire specimen cross section When the preferred growth directions of both grains are both non-parallel to the heat flow direction and combined with a large divergence angle, a third grain may appear between the two grains and eventually extend to the entire specimen cross-section.