EVOLUTION OF MICROSTRUCTURE AND MECHANICAL PROPERTIES OF THE Ni-25Al-27.5Fe-1.0Nb INTERMETALLIC ALLOY AFTER THERMAL MECHANICAL TREATMENT

摘要：

The evolution of microstructure and mechanical properties of the Ni-25Al-27.5Fe-1.0Nb intermetallic alloy after thermal mechanical treatment (TMT) was systematically investigated by means of X-ray diffractometry (XRD), scanning electron microscopy (SEM) with electron dispersive spectrum (EDS) capability, and atmosphere-controlled tensile test at room temperature with different strain rate. The results of XRD reveals that a matrix of β phase (Ni, Fe) Al type ordered bcc structure and a precipitated γ phase (NUFe fcc solid solution) co-exist in this alloy after TMT. The dendritic microstructure of the as-cast alloy was eliminated after TMT process. In parallel, a refined and homogeneous distributed lath precipitates can be obtained after annealing at 820 for 4 hr. Additionally, this alloy presents a relative high strength as well as ductile mechanical behavior (UTS-1320 MPa and ε~8％, respectively) at room temperature in air. A 30％ improvement in yield strength is suggested to be contributed by the refined microstructure from the TMT. Moreover, the tensile strength and ductility of this alloy exhibit insensitive response with respect to the loading strain rate at room temperature.

关键词： Intermetallic alloy nickel aluminide thermal mechanical treatment mechanical properties

作者: CHIH-CHIANG FU JASON SHIAN-CHING JANG HAN-CHANG TSAI TSUNG-HSIUNG LI

作者单位: Department of Materials Science and Engineering, I-Shou University, ＃1, Section 1, Hsueh-Cheng Road, Ta-Hsu Township, Kaohsiung, 84008, Taiwan

会议类型: 国际会议

会议名称: 第五届先进材料与加工国际会议(Fifth International Conference on Advanced Materials and Processing ICAMP-5)

会议地点: 哈尔滨

会议语种:英文

页码: 1053-1059

在线出版日期: 2008-09-03（万方平台首次上网日期，不代表论文的发表时间）