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Influence of ZrO2 addition on nickel aluminide layerson pure nickel substrate prepared by pack cementation |
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| รหัสดีโอไอ | |
| Creator | 1. Sirichai Leelachao 2. Thamvee Manochayakorn 3. Yasinthon Chanapol 4. Patama Visuttipitukul |
| Title | Influence of ZrO2 addition on nickel aluminide layerson pure nickel substrate prepared by pack cementation |
| Publisher | Research and Development Office, Prince of Songkla University |
| Publication Year | 2022 |
| Journal Title | Songklanakarin Journal of Science an Technology (SJST) |
| Journal Vol. | 44 |
| Journal No. | 3 |
| Page no. | 760-766 |
| Keyword | pack aluminization, diffusion coatings, thermodynamic activity, reduction reaction, zirconium-containing intermetallics, high-temperature oxidation |
| URL Website | https://rdo.psu.ac.th/sjst/index.php |
| ISSN | 0125-3395 |
| Abstract | This study aims to apply pack aluminization which contains ZrO2 powder to develop NixAly layers on the surface ofpure Ni substrate to investigate the effect of ZrO2 content on phase development and oxidation behavior of the aluminized Ni.The surface of pure Ni substrate was aluminized at 1,000 ยฐC for 6.25 hrs using a pack-cementation with three ZrO2 contents inthe pack mixture. Aluminized specimens were subjected to cyclic oxidation with air-cooling in ambient air at 1,000 ยฐC. Ascanning electron microscope equipped with energy-dispersive X-ray spectroscopy and an X-ray diffractometer (XRD) wereused for phase analyses. Layers of coatings consisted ฮฒ-NiAl, ฮณโ-Ni3Al and Al-alloyed ฮณ-Ni. Thicknesses decreased withincreasing ZrO2 contents. Incorporated Zr was in the forms of intermetallics. The absence of ฮด-Ni2Al3 indicated a reduction ofdiffusing Al activity. While the specimen with moderate ZrO2 content showed parabolic oxidation kinetics, the multiple linearkinetics along with the high-exponent power-law oxidation were observed in the oxidized specimens prepared at otherconditions. The addition of ZrO2 in pack aluminization enables a modification of the thermodynamic Al activity. The stable ฮฑAl2O3 formation was found to be promoted by the Zr addition rather than a higher Al concentration of aluminides. |
