微合金耐火钢中AlN界面处碳化物表征

Characterization of carbides at AlN/matrix interface in micro-alloyed fire resistant steel

将含氮Nb-Mo-V微合金耐火钢在1200℃固溶0.5 h后淬火,在650℃回火10 h,用透射电子显微镜(TEM)和原子探针层析技术(APT)研究氮化铝(AlN)/基体界面处碳化物的析出。结果表明,方形六方结构AlN的某一个表面是密排面(0001),面心立方结构的钒钼复合碳化物(V,Mo)C容易在AlN(0001)密排面/基体界面处析出并沿其自身〈111〉方向长大,并与AlN共格。(V,Mo)C与AlN之间的晶体学关系为:[110](V,Mo)C//[11 20]AlN,(111)(V,Mo)C//(0001)AlN。

The carbides at aluminum nitride （A1N）/matrix interface in a micro-alloyed fire resistant steel tempered at 650 ℃ for 10 h after solution treatment at 1200 ℃ for 0.5 h were characterized by transmission electron microscopy （TEM） and atom probe tomography （APT）. The results show that one of square HCP A1N surfaces is （0001） close packed plane, and FCC complex carbides （V, Mo）C precipitate at the A1N/matrix interface, grow along （ 111 ） direction and are coherent with A1N. The crystallographic orientation relationship between（ V, Mo） C and A1N are [ 110] （V,Mo）c//[11 20] AIN, （ 111 ） （V,Mo） C//（0001） A1N.