High temperature oxidation behaviors of
Ti-Cr alloys with Laves phase TiCr2
Ti-Cr alloys with Laves phase TiCr2
(1.State Key Laboratory for Powder Metallurgy,
Central South University, Changsha 410083, China;
2.Department of Automobile and Electromechanical Engineering,
Changsha Communications University, Changsha 410076, China；
3. School of Materials Science and Engineering, University of
Science and Technology Beijing, Beijing 100083, China)
Central South University, Changsha 410083, China;
2.Department of Automobile and Electromechanical Engineering,
Changsha Communications University, Changsha 410076, China；
3. School of Materials Science and Engineering, University of
Science and Technology Beijing, Beijing 100083, China)
Abstract: The high temperature oxidation behaviors of Ti-Cr alloys containing 18%～35%Cr with Laves phase TiCr2 were investigated at 650～780℃ for exposure up to 104h. The results reveal that chromium content has critical significance to the oxidation resistance of the alloys. The scaling rates of the alloys with less than 21%Cr are higher than those measured for pure titanium, but for the alloys with more than 26%Cr their scaling rate is lowered by 1～2 times, under the same oxidizing conditions. Both an external and an internal oxidation layers were observed. The oxidation resistance enhancement by chromium alloying is contributed to the formation of a continuous and compact chromic oxide interleaf in the scale. Oxidation temperature significantly affects the scaling rates of Ti-Cr alloys, and the mass gain is doubled with a temperature change from 650℃ to 700℃ or from 700℃ to 780℃, for the same exposure duration. TiCr2 shows no negative influence on the high temperature oxidation resistance of the alloys.
Key words: Laves phase; TiCr2；Ti-Cr alloy；oxidation