摘要
镍基高温合金中的碳化物(MC),其初始形态和在接近平衡条件下生长的形态均为八面体。应用PBC(Periodic Bond Chains)理论对MC的界面分类表明,{100},{110}和{111}面为F面,{212}面为S面。对各F面的附着能计算表明,{111}面是MC最易显露的晶面。从而证实了MC从高温合金熔体中生长的理想形貌是以{111}面为外表面的八面体。文章认为MC的一种生长基元为由中心金属原子和6个碳原子组成的八面体配位体,其生长机制为沿{111}面层状堆积。
The categories of crystal faces for MC carbides in Ni-base superalloysby means of PBC theory confirm that {100}, {110} and {111} are F faces, and{212} are S faces. The caculations of attachmemt energy of each F face show that{111} are most important faces. It has also inferred that one of the growth unitsof MC carbides may be octahedrol molecula which consist of a metal atom sur-rounded by an octahedron of six carbon atoms. The attachment scheme of octahedralunits onto crystal should be layer grdwth mechanism on the {111} faces.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
1989年第4期A282-A287,共6页
Acta Metallurgica Sinica
基金
国家自然科学基金
