摘要
通过光学显微镜、扫描电镜和透射电镜对Zr-Sn-Nb系两种合金淬火时效样品进行观察分析,研究了合金元素Cu对锆合金淬火后微观组织的影响及在时效过程中对第二相析出规律影响。结果表明：淬火态样品中没有第二相析出,且Cu元素的添加可以细化晶粒及淬火板条组织,提高合金硬度;经过时效处理后,第二相首先在晶界位置析出;随着保温时间的延长,合金元素扩散充分。透射电镜结果显示,Cu元素促进第二相形核析出以及细化第二相尺寸。
Through the quenching and aging microstructure of Zr-Sn-Nb series, noted as N1 and N2 respectively, they were investigated by optical microscopy（OM）, scanning electron microscope（SEM） and transmission electron microscopy（TEM）. The effects of Cu element on the microstructure of zircaloy after quenching and the precipitate regularity of the second phase during aging were studied. It can be revealed that the grain size and lath structure are refined considerably with Cu addition leading to improvement of micro-hardness, while no secondary phases are found in the as-quenching samples of both alloys. The secondary phases are firstly nucleated at the grain boundary after aging, and then form in the grain along with the extending of aging time due to the diffusion rate. The TEM results indicate that the Cu element could promote the precipitation nucleation and decrease the size of the second phases.
出处
《热加工工艺》
CSCD
北大核心
2018年第2期1-4,10,共5页
Hot Working Technology
基金
国家自然科学基金项目(51371202)
