Zr-4合金中氢化物析出的TEM研究  

TEM Study of Zirconium Hydrides Precipitated in Zr-4 Alloy

作　　者：窦娜娜[1] 宋西平[1] 杨云[1] 赵超[1] 李如峰[1] 

机构地区：[1]北京科技大学新金属材料国家重点实验室,北京100083

出　　处：《稀有金属材料与工程》2016年第1期97-101,共5页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(21171018;51271021)

摘　　要：利用透射电镜(TEM)研究了Zr-4合金吸氢后析出氢化物的类型、形貌及其位相关系。结果表明,随着吸氢量的增加,Zr-4合金中依次析出了δ-Zr H_(1.6)及ε-Zr H_(1.8)氢化物。δ氢化物主要以板条状从α-Zr基体上析出,二者的取向关系为(0001)α//(001)δ,[20]α//[110]δ。ε氢化物以针状形貌从δ氢化物中析出,析出的ε氢化物的密排面(1)与δ氢化物的密排面(1)平行,二者的取向关系为(1)δ//(1)_ε,[12]_δ//[011]_ε。高分辨观察进一步表明,δ-Zr H_(1.6)及ε-ZrH_(1.8)氢化物的晶格点阵均出现了严重的扭曲变形,说明相变存在较大的应力集中。The type, morphology and orientation relationship of the hydride precipitates in a hydrogen absorbed Zr-4 alloy have been studied by transmission electron microscopy（TEM）. The results show that δ-Zr H1.6and ε-Zr H1.8 hydrides are found to precipitate successively with the increase of hydrogen absorption. The δ-Zr H1.6 hydrides are mainly in the form of lath and precipitate in the orientation relationship of（0001）α//（001）δ and [20]α//[110]δ with the α-Zr matrix, while the ε-Zr H1.8 hydrides are in acicular morphology and precipitate in the orientation relationship of（  1 ）δ //（ 1）ε and [12]δ//[011]ε with the δ-Zr H1.6hydrides. The close-packed planes of these two hydrides are identified to be parallel. High-resolution TEM observation shows that there exists a great deal of distortion inside the crystal lattice of the δ-Zr H1.6 and ε-Zr H1.8 hydrides, indicating a large stress concentration produced during their precipitation.

关 键 词：ZR-4合金 氢化物 TEM 位相关系 

分 类 号：TG146.414[一般工业技术—材料科学与工程] TK91[金属学及工艺—金属材料]