W.J. Park
,
S. Ahn
,
R. Schmees
,
and Nack J. Kim(1)(Center for Advaned Aerospace Materials
,
POSTECH. Pohang 790-784
,
Korea )2)(Research Institute of industrial Science & Technology
,
Pohang 790-600
,
Korea )3)(Pratt and Whitney
,
West Palm Beach
,
FL
,
USA Manuscript received 26 August 1996)
金属学报(英文版)
The effects of additions of Ti and W on microstructure and mechanical properties of rapidly solidified Al-Fe-V-Si alloys were investigated. Alloy powders were produced by the centrifugal rotary atomization process. After atomization, powders were screened to various mesh sizes to see the effect of powder size on the mechanical properties.These Powders were consolidated into billets using conventional powder metallurgy process, and then extruded into bar form.Microstructural analysis shows that the W addition results in the heterogeneous microstructure.On the other hand, the Ti addition refines the microstructure.Alloy containing both Ti and W has the highest thermal stability of the dispersoid. These variations in the microstructure are well reflected in the mechanical properties in that the Ti containtng alloys (with or without W) have the higher strength and ductility than the W containing alloy. It also shows that the alloys made of the coarser powders have better combinations of strength and ductility than those made of the finer powders.
关键词:
:rapid solidification
,
null
,
null
仝兴存
,
沈宁福
,
柳百成
金属学报
研究了快速凝固Al-Fe-Ti-C合金的显微结构及退火过程中的相变。初始快凝态组织由α-Al微胞晶组成,在胞晶边界分布着较大并拉长的非晶相;在胞晶内部则为细小弥散的球状亚稳Al_6Re相(底心正交结构),Ti和C全部过饱和固溶于α-Al中。当773K退火5h时,非晶相转变为α_T-AlFeSi相(斜方结构),Al_6Fe相部分转变为片状Al_3Fe相(底心单斜结构),部分长大但仍保持球状和底心正方结构过饱和固溶于α-Al基体中的Ti和C则以TiC形式弥散析出。
关键词:
快速凝固
,
Al-Fe-Ti-C alloy
,
microstructure
,
annealing
仝兴存
,
方鸿生
,
柳百成
金属学报
将常规熔铸工艺与快速凝固技术相结合,成功地制备出Al-TiC自生复合材料.常规熔铸Al-TiC自生复合材料中TiC的体积分数为14.5%,颗粒尺寸为0.2-1.0μm,一般呈聚集态分布;与类似工艺条件下的人工复合材料相比,业已表现出较好的综合力学性能.快凝及热挤成型以后,TiC的体积分数约为13.5%,颗粒尺寸减至40-80nm,并弥散分布于晶粒尺寸为0.30-0.80μm的α-Al基体上,室温拉伸强度增加了约100MPa,表现出良好的高温力学性能.
关键词:
快速凝固
,
Al-TiC
,
in situ processed composites.