文章信息/Info

Title:

Development of SiO2-Based Protective Coatings on TiAl Alloy

文章編號:

1674-3962(2022)05-0345-09

作者:

嚴(yán)豪杰; 伍廉奎; 曹發(fā)和

（中山大學(xué)材料學(xué)院，廣東 深圳 518107）

Author(s):

YAN Haojie;  WU Liankui ;  CAO Fahe

(School of Materials, Sun Yat-sen University, Shenzhen 518107, China)

關(guān)鍵詞:

TiAl合金; SiO2涂層; 高溫氧化; 表面改性; 防護(hù)涂層

Keywords:

TiAl alloy;  silica coating;  high temperature oxidation;  surface modification;  protective coating

分類號:

TG174.45

DOI:

10.7502/j.issn.1674-3962.202110002

文獻(xiàn)標(biāo)志碼:

A

摘要:

TiAl合金具有密度低、比強(qiáng)度高和高溫抗蠕變性能好等優(yōu)點，在航空航天及汽車工業(yè)等領(lǐng)域的高溫結(jié)構(gòu)部件中具有廣闊的應(yīng)用前景。然而，抗高溫氧化性不足的問題限制了其應(yīng)用。SiO2涂層結(jié)構(gòu)致密，具有良好的化學(xué)穩(wěn)定性和熱穩(wěn)定性，可有效改善TiAl合金的抗高溫氧化性能，引起了研究人員的關(guān)注。然而，純SiO2涂層存在結(jié)構(gòu)單一、涂層與TiAl基體熱膨脹系數(shù)差異較大、在長期高溫環(huán)境服役時界面易失穩(wěn)等問題。為此，TiAl合金表面SiO2復(fù)合涂層應(yīng)運而生，主要包括在SiO2涂層和基體之間引入其他中間層形成多道防護(hù)層,以及將SiO2涂層作為中間層構(gòu)筑復(fù)合涂層。簡要介紹了TiAl合金的氧化行為和改善合金抗高溫氧化性能的方法，綜述了近年來國內(nèi)外TiAl合金表面SiO2防護(hù)涂層的研究進(jìn)展，討論了SiO2涂層的制備方法和原理、高溫氧化行為、氧化膜結(jié)構(gòu)及其防護(hù)機(jī)理，并展望了未來SiO2防護(hù)涂層的發(fā)展趨勢。

Abstract:

Due to low density, high specific strength, and good creep resistance, TiAl alloy has been considered as the high-temperature structure candidates in aerospace and automotive industries. However, the poor high-temperature oxidation resistance limits its applications. The pure SiO2 coating with compact structure, good thermal and chemical stability can effectively improve the high temperature oxidation resistance of TiAl alloy. However, there are some issues when the SiO2 coating with simplified structure is exposed to air at high temperature for long-term, such as the large difference in the thermal expansion coefficients between SiO2 coating and TiAl substrate, and poor stability of the coating and substrate interface. To deal with these issues, SiO2 composite coating emerges, including the introduction of intermediate layer between the SiO2 coating and TiAl substrate, preparation of glass ceramic-based composite coating using the SiO2 coating as the intermediate layer. This paper briefly introduces the oxidation behavior of TiAl alloy and the methods to improve the oxidation resistance of TiAl alloy. The research progress of the silica-based protective coating at home and abroad was reviewed. The preparation methods and principles, high temperature oxidation behavior, structure of oxide scale and protective mechanism of silica-based coatings were discussed. The development trend of silica-based coatings on TiAl alloy in the future was prospected.