Pressure-induced excellent corrosion resistance of Ti-45Al-8Nb alloy

In this paper, high pressure was used to improve the corrosion resistance of Ti-45Al-8Nb alloy. It achieves wider passive region, higher Er, smaller Ip and Icorr value that is 53.3% lower than that of the as-cast alloy. Such excellent corrosion resistance is caused by the coaction of increased Al solution and sharp decrease of γ-TiAl phase brought by high pressure, which is beneficial to improving the stability and repairability of the passive film on the surface of the alloy. Consequently, Ti-45Al-8Nb solidifying under high pressure exhibits the best corrosion resistance compared to as-cast alloy and many other TiAl alloys.