Abstract
The hot-corrosion behavior of Ti-50Al,Ti-48Al-2Cr-2Nb, and Ti-50Al10Cr alloys was investigatedin (Na, K)2SO4 andNa2SO4 + NaCl melts. TiAlintermetallics showed much better hot-corrosionresistance in (Na, K)2SO4 at900°C than the Ni-base superalloy K38G. Two types ofcorrosion products formed on Ti-50Al: some areas werecovered with a continuous Al2O3 scale, whereas otherareas formed a mixed Al2O3 +TiO2 scale; TiS existed at the scale-alloyinterface. A mixed Al2O3 +TiO2 scale formed on Ti-48Al-2Cr 2Nb, and nosulfide was found beneath the scale. An adherentAl2O3 scale, however, formed onTi-50Al-10Cr, which provided excellent hot-corrosionresistance. All three alloys suffered severe hotcorrosion in Na2SO4 + NaCl meltsat 850°C. A mixed Al2O3 +TiO2 scale formed on all three alloys andmany voids and pits existed in the scale-alloy interface. Thehot-corrosion mechanisms are discussed.
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Tang, Z., Wang, F. & Wu, W. Hot-Corrosion Behavior of TiAl-Base Intermetallics in Molten Salts. Oxidation of Metals 51, 235–250 (1999). https://doi.org/10.1023/A:1018818622547
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DOI: https://doi.org/10.1023/A:1018818622547