(1.中南大學(xué)粉末冶金研究院粉末冶金國(guó)家重點(diǎn)實(shí)驗(yàn)室，長(zhǎng)沙410083；
2.中南大學(xué)材料科學(xué)與工程學(xué)院，長(zhǎng)沙410083；
3.中南大學(xué)粉末冶金研究院，長(zhǎng)沙410083)
摘 要: 采用高通量的合金設(shè)計(jì)方法設(shè)計(jì)一種新型鎳基單晶高溫合金CSU-B2，并對(duì)該合金進(jìn)行了一系列的研究。結(jié)果表明：該合金在鑄態(tài)下樹枝晶分布均勻，枝晶間距約為500μm，沒(méi)有三次枝晶出現(xiàn)。通過(guò)對(duì)合金進(jìn)行固溶和時(shí)效處理，合金中的γ′析出相呈現(xiàn)方塊狀，平均顆粒尺寸為0.5~0.8μm。在1100和1150 ℃下對(duì)合金的抗氧化性能進(jìn)行研究發(fā)現(xiàn)，試樣單位面積質(zhì)量隨時(shí)間的變化遵循類拋物線的規(guī)律，在氧化層的下面都存在著γ′相消失的區(qū)域。最后對(duì)合金的高溫拉伸性能進(jìn)行了表征，在760 ℃時(shí)，合金的屈服強(qiáng)度為706MPa；在980℃時(shí)，合金的屈服強(qiáng)度為484MPa。在兩個(gè)溫度下，試樣的斷裂為兩種不同的機(jī)制。
關(guān)鍵字: 鎳基單晶高溫合金；熱處理；高溫氧化；高溫拉伸
（1.State Key Laboratory of Powder Metallurgy, Research Institute of Powder Metallurgy,
Central South University, Changsha 410083, China;
2. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
3. Research Institute of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:A new nickel-base single crystal superalloy named CSU-B2 was designed by high-throughput alloy design method and a series of investigations were done to characterize the superalloy. The results show that the primary dendrites are uniformly distributed and the spacing size in the as-cast alloy is about 500 μm, where tertiary dendrite is absent. After solution and ageing treatments, theγ′ prime precipitates are cuboidal-shaped and the average size is 0.5-0.8μm. The oxidation-resistance property of the new alloy is evaluated at 1100 and 1150 ℃, the results show that the oxide growth of the new alloy obeys the parabolic law for both under isothermal and cyclic oxidation, and there both have aγ′ free zone under the oxide scale. The yield strengths under the temperature of 760 and 980 ℃are measured to be 706 and 484 MPa, respectively, and two different mechanisms govern the failure processes.
Key words: nickel-base single crystal superalloy; heat treatment; high temperature oxidation; high temperature tensile
