LZO对热障涂层中粘结层氧化的抑制行为研究

Study on the inhibition behavior of LZO on the oxidation of bond coat in Thermal Barrier Coatings

摘要:

为了阐明LZO对热障涂层(TBCs)中粘结层氧化的抑制作用,利用爆炸喷涂(D-gun)在310S基体上制备NiCoCrAlY粘结层,大气等离子(APS)制备单陶瓷8YSZ涂层和双陶瓷LZO/8YSZ涂层。采用SEM、EDS和XRD表征了不同结构TBCs喷涂态及高温氧化后的微观组织和相结构。结果表明：1100 ℃下等温氧化(100小时)后双陶瓷LZO/8YSZ与单陶瓷8YSZ热障涂层相对氧化增重分别为2.82 mg/cm₂和3.13 mg/cm₂,TGO生长速率常数K_p分别为5.79×10_-2μm₂/h和6.26×10_-2μm₂/h,厚度分布范围分别为3.75-5.25 μm和5-5.5 μm。相比单陶瓷TBCs,LZO/8YSZ双陶瓷TBCs中粘结层表现出氧化增重少、TGO生长速率低、粘结层中β相转变慢等明显特征。

Abstract:

In order to clarify the inhibitory effect of LZO on the oxidation of bond-coat in thermal barrier coatings (TBCs), NiCoCrAlY bond-coat was deposited on 310S substrate by Detonation gun spraying, and single ceramic 8YSZ coating and LZO/8YSZ double ceramic coating were deposited by air plasma spraying technology. The microstructure and phase structure of TBCs before and after high temperature oxidation were analyzed by SEM, EDS and XRD. The results showed that the relative oxidation weight gain of the double ceramic LZO/8YSZ and the single ceramic 8YSZ structure was 2.82 mg/cm2 and 3.13 mg/cm2, respectively. Corresponding the TGO growth rate constant Kp was 5.79 ×10- 2 μm2 / h and 6.26×10- 2 μm2 / h, respectively. And the corresponding thickness distribution range was 3.75-5.25 μm and 5-5.5 μm, respectively after isothermal oxidation (100 hours) at 1100 °C. Compared with the single ceramic 8YSZ TBCs, TGO exhibited obvious characteristics were less oxidation weight gain, low growth rate, and slow β phase transition in bond-coat of the LZO/8YSZ double ceramic TBCs.