任鑫
,
汪信
,
王福会
中国腐蚀与防护学报
用SEM\XRD和EPMA等手段，研究了溅射NiCrAlY涂层渗Al前后在1000℃和1100℃的高温氧化行为。结果表明，溅射涂层在1000℃形成了单相的α－Al2O3而具有优异的抗氧化性能；但在1100℃由于Al的过度消耗而失去保护作用。渗铝涂层在1000℃快速增长θ－Al2O3相，使其抗氧化性能稍逊于溅射涂层；在1100℃表面形成了以α－Al2O3为主的保护膜，抗氧化性能优于溅射涂层。
关键词:
氧化
,
sputtered coating
,
aluminizing
C.G. Zhou
,
H.B. Xu and S.K. Gong (Department of Materials Science and Engineering
,
Beijing University of Aeronautics and Astronautics
,
Beijing 100083
,
China) K. Y. Kim (Department of Materials Science and Engineering
,
Pohang University of Science and Technology
,
San31
,
Hyoja-dong
,
Pohang 790-784 Korea)
金属学报(英文版)
The halide-activated pack cementation method is utilized to deposit aluminide coat- ings on TiAl alloys. Emphasis is placed on the effect of alloying elements on the aluminizing behavior of TiAl alloy. The addition of a small amount of Nb or Cr in the TiAl improves significantly the aluminizing kinetics of TiAl alloys by increasing the solid-state division of Al through the formation of stable TiAl3 layer. The TiAl3 layer formed on the TiAl alloyed with Nb or Cr has better toughness than the TiAl3 formed on the non-alloyed TiAl. The reason for better toughness of the coating formed on TiAl is that partial TiAl3 with tetragonal structure was changed to high symmetry cubic L12 structure since Nb or Cr was dissolved into TiAl3. The TiAl3 layer formed on the TiAl alloyed with Nb or Cr has much better oxidation resistance than the TiAl3 layer formed on the non-alloyed TiAl. It is attributed to change in the crystal structure of TiAl3 from the brittle tetragonal DO22 to the ductile cubic L12 by addition of small amount of Nb or Cr.
关键词:
TiAl
,
null
,
null
,
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