摘要
通过对4种不同Re(3%—6%,质量分数,下同)和Ru(0%和3%)含量的镍基单晶高温合金铸态和热处理态组织的观察和成分分析,研究了Re和Ru对元素偏析以及热处理过程中组织演化的影响.结果表明,Re和Ru均会加剧铸态试样中的元素偏析,但经过固溶处理后,Ru对合金元素的残余偏析的影响不大.随着Re含量的增加和Ru的加入,热处理态组织中γ'相尺寸减小,形貌的立方程度明显增加.电子探针(EPMA)对成分的测量结果显示,Al,Ia和Ni偏析于γ;沉淀相,Re和Cr强烈地偏析于γ相,而Ru和W向γ相的偏析程度则相对较低.Re含量的增加明显增大了Re_1Cr,Co和W等元素向γ相的偏析,而Ru的加入则使得这些TCP相形成元素向γ相的偏析程度略有降低.
The influence of Re and Ru on segregation and microstructure evolution during heat treatment has been investigated in four Ni-based single-crystal superalloys with varied contents of Re （3%--6%, mass fractions） and Ru （0% and 3%）. The additions of Re and Ru lead to the more severe segregation of alloying elements in as-cast structures. However, the effects of Ru on as-cast segregation can be neglected after the stepwise solution heat treatments. The additions of Re and Ru lead to the lower γ＇-coarsening rate, more cuboidal γ＇-morphology and reducedγ＇-size. Electron microprobe analysis （EPMA） indicates that Al, Ta and Ni partition to the γ＇-precipitates, whereas Re and Cr strongly partition to the γ-matrix. In comparison to Re and Cr, Ru and W show the less tendency to partition to the γ-matrix. Additionally, Re increases the supersaturation of Re, Cr, Co and W in the γ-matrix, whereas Ru only slightly suppresses the partition of these TCP-forming elements to the γ-matrix.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2012年第7期845-852,共8页
Acta Metallurgica Sinica
基金
国家自然科学基金项目50931004
50827102和50771081
国家重点基础研究发展计划项目2010CB631202和2011CB610406资助~~
关键词
RU
RE
单晶高温合金
微观组织
偏析
γ'相形貌
Ru, Re, single-crystal superalloy, microstructure, segregation, γ-morphology
