摘要
采用籽晶法,研究了不同角度的初始枝晶对高温合金DZ417G定向凝固组织影响。结果表明,在拉速为100μm/s的条件下,当初始枝晶的生长方向与轴向方向夹角较小时,获得生长方向一致的枝晶组织;当初始枝晶的生长方向与轴向方向夹角较大时,在枝晶尖端靠近坩埚臂的一侧有杂晶形成,并在截面变化后延续和促进了杂晶的生长。从枝晶臂的熔断和竞争生长角度对实验结果进行了分析。
Using seed crystal, influence of different dendrite orientations on the microstructures of the superalloy DZ417 G during directional solidification was investigated. The results indicated that the growth direction of dendrites did not change and no stray grain appeared at a small deviation angle from axis orientation. Nevertheless, with the increase of the deviation angle from axis orientation, the stray grains grew up. When section gets large, the stray crystal growth is promoted. Above phenomena were analyzed on the base of theories of the detachment of grain fragments from columnar dendritic fronts and competitive grain growth.
出处
《钢铁研究学报》
CAS
CSCD
北大核心
2011年第S2期369-372,共4页
Journal of Iron and Steel Research
基金
国家重大基础研究项目(2011CB610404)
关键词
定向凝固
高温合金
杂晶
竞争生长
变截面
directional solidification
superalloy
stray grain
competitive growth
variable cross-section