The microstructure and mechanical properties of five alloys with nominal compositions of Ti–45Al–2W–xC (in at.%), where x is ranging from 0.4 to 2.0 at.%, were studied. The alloys were prepared by vacuum induction melting in graphite crucibles, followed by centrifugal casting into a graphite mould. The as-cast alloys were subjected to hot isostatic pressing and heat treatment consisting of solution annealing, cooling at a constant rate and stabilisation annealing. The microstructure of the heat-treated alloys consists of equiaxed α₂(Ti₃Al) + γ(TiAl) lamellar grains surrounded by γ grain boundaries with a small amount of β/B2 particles. The α₂-α₂ interlamellar spacing λ decreases with increasing carbon content until a solubility limit of carbon is achieved. The increase in carbon content above the solubility limit leads to the formation of primary Ti₂AlC particles during solidification and an increase in the amount of γ phase at grain boundaries. Vickers microhardness of lamellar grains depends on the carbon content and interlamellar spacing λ. The studied Ti–45Al–2W–0.8C and Ti–45Al–2W–1.2C alloys show improved creep resistance at 800 °C compared to that of the reference carbon-free TiAl–W and carbon-containing TiAl–Nb based alloys with fully lamellar, nearly lamellar, convoluted or pseudo-duplex microstructure.

研究了标称成分为 Ti-45Al-2W-xC（以 at.% 为单位）的五种合金的微观结构和机械性能，其中 x 的范围为 0.4 至 2.0 at.%。这些合金是通过在石墨坩埚中真空感应熔炼制备的，然后离心铸造成石墨模具。铸态合金经过热等静压和热处理，包括固溶退火、恒速冷却和稳定退火。热处理合金的显微组织由等轴α ₂ (Ti ₃ Al) + γ(TiAl) 层状晶粒组成，周围有少量β/B2 颗粒的γ 晶界。α ₂ -α ₂层间距 λ 随着碳含量的增加而减小，直到达到碳的溶解度极限。超过溶解极限的碳含量的增加导致在凝固过程中形成初级Ti ₂ AlC颗粒并且在晶界处γ相的量增加。层状晶粒的维氏显微硬度取决于碳含量和层间距λ。所研究的 Ti-45Al-2W-0.8C 和 Ti-45Al-2W-1.2C 合金与参考的无碳 TiAl-W 和含碳 TiAl-Nb 基合金相比，在 800 °C 下表现出更高的抗蠕变性完全层状、近层状、卷曲或假双相微结构。