高氢量氢化的Ti-6Al-4V合金中氢化物的组织结构研究

STRUCTURE OF HYDRIDES IN HIGHLY HYDROGENATED Ti-6Al-4V ALLOYS

研究了含氢最为0.16,0.58,0.87,1.49wt—%的Ti—6Al—4V—H合金中出现的各种氢化物,结果表明:氢超过0.58%时,合金中已有Ti_3Al相析出,同时,随着氢含量的增加,氢化物的形态逐渐由低氢的粗板条变到高氢的窄板条,后者组织明显细化,在含氢1.49%的试样中,还观察到四方点阵的氢化物和块状氢化物,并发现孪晶氢化物,根据孪晶氢化物的电子衍射花样的特点,可以简便地判别氢化物为立方或四方结构。

The microstructure and various hydrides precipitated in Ti--6Al--4V alloys con- taining hydrogen 0.16, 0.58, 0.87, 1.49 wt--%, respectively, have been studied by means of TEM and X--ray diffraction. The Ti_3Al phase may precipitate when [H] over 0.58 wt--%. In the same time, the morphology of hydrides gradually changed from rugged sheets to narrow laths as [H] contents increased. The microstructure of highly H--doped alloys is obviously fine. A mas- sive hydride and the hydride with tetragonal lattice were observed in the specimen containing 1.49 wt--% H. The twin hydrides were found in the alloys with different H contents and the electron diffraction patterns of the twin hydrides can be served as a simple criterion for distin- guishing the cubic and tetragonal structures.