F. H.(Sam) Froes
,
C. Suryanarayana
,
and D. Mukhopadhyay (Institute for Materials and Advanced Processes (IMAP)
,
University of Idaho
,
Moscow
,
ID 83844-3026
,
USA)C-G. Li(BlM
,
P.O. Box 81
,
Beijing
,
100095
,
P.R. CHINA)K. Brand(On leave from Institut fur Werkstoffwissenshaft
,
Technische Universitst Dresden
,
07062 Dresden
,
Germany
,
at IMAP)
金属学报(英文版)
Mechanical alloying (MA), a solid-state powder processing method, is a "far from equilibrium" synthesis technique which allows development of novel crystal structures and microstructures, leading to enhanced physical and mechanical properties. The ability to synthesize a variety of alloy phases including supersaturated solid solutions, nanocrystalline structures, amorphous phases and intermetallic compounds themselves is discussed. No extension of solubility using MA has been observed in the intermetallics studied. Nanostructured grains were observed in all compositions. Long time milling generally resulted in amorphous phase formation in large part because of the increase in grain boundary energy/mole with reduced grain size; good agreement with the Miedema model for amorphization was obtained in the Al-Fe system. Generally an anneal was required to form the intermetallic after MA; however,intermetallics with a large negative enthalpy of formation were detected in the MA condition. A study of the hot isostatic pressing of γ-TiAl powders produced by MA demonstrated that full density can be achieved at least 400℃ below the normal temperature required for conventional powder, that is 725℃ or below. Nanometered sized grains (≤100nm)were observed after HIP'ing up to 850℃.
关键词:
: Intermetallics
,
null
,
null
王毅
,
索红莉
,
马麟
,
王建宏
,
李孟晓
,
孟易辰
,
刘敏
稀有金属材料与工程
采用中频感应熔炼方法制备Ni-5at％W合金锭,经锻造和热轧后,再冷轧到50 m长,厚度为60 μm的带材.随后在800～1200℃进行再结晶退火处理.在兼顾“高织构”和“浅晶界”要求下,得出1100℃/0.5h是Ni5W合金基带最佳的退火工艺.根据X射线衍射(XRD)和电子背散射衍射技术(EBSD)结果,在1100℃/0.5 h时该Ni5W合金基带的再结晶立方织构含量达到98.9％(≤10°),且晶粒尺寸均匀.退火后的Ni5W合金基带扫描半高宽(FWHM)值和孪晶界含量接近德国Dresden公司商业化Ni5W合金基带的水平.
关键词:
再晶界退火
,
立方织构
,
晶界
,
涂层导体
