The wetting behavior of NiAl and NiPtAl on polycrystalline alumina

نویسندگان

  • A. Gauffier
  • E. Saiz
  • A. P. Tomsia
  • P. Y. Hou
چکیده

In order to understand the beneficial effect of Pt on the adherence of thermally grown alumina scales, sessile drop experiments were performed to study the wetting of poly-crystalline alumina by nickel-aluminum alloys with or without platinum addition where the amount of Pt ranged from 2.4 to 10 at.%. Subsequent interfacial structure was evaluated using atomic force microscopy. Platinum addition enhances the wettability of NiAl alloys on alumina, reduces the oxide/alloy interface energy and increases the interfacial mass transport rates.

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تاریخ انتشار 2008