本文關(guān)鍵詞： 熱震 熱生長氧化物 失效機(jī)理 結(jié)構(gòu)演變　出處：《無機(jī)材料學(xué)報(bào)》2015年12期 　論文類型：期刊論文

【摘要】：采用低溫超音速等離子噴涂(LT-HVOF)在鎳基高溫合金基體上制備了Ni Co Cr Al YTa粘結(jié)層,使用大氣等離子噴涂(APS)在粘結(jié)層上`制備了7wt%Y2O3-Zr O2(7YSZ)陶瓷層。基于動(dòng)態(tài)試驗(yàn)即熱震實(shí)驗(yàn)研究了粘結(jié)層的擴(kuò)散氧化機(jī)制,探討了陶瓷層的燒結(jié)及相變過程并觀察了涂層的結(jié)構(gòu)演變。實(shí)驗(yàn)結(jié)果表明:動(dòng)態(tài)熱循環(huán)下隨著熱震次數(shù)的增加,粘結(jié)層組元擴(kuò)散氧化形成熱生長氧化物(TGO)且厚度逐漸增加。此外,粘結(jié)層組元在溫度梯度下沿陶瓷層內(nèi)部裂紋向高溫區(qū)擴(kuò)散,最終在陶瓷層表面裂紋區(qū)域出現(xiàn)大量的金屬氧化物,同時(shí)粘結(jié)層組元的擴(kuò)散有助于陶瓷層的燒結(jié),導(dǎo)致其顯微硬度逐漸增大,而粘結(jié)層由于Kirkendall效應(yīng),其內(nèi)部出現(xiàn)大量的孔洞導(dǎo)致其顯微硬度逐漸降低。另外,陶瓷層在相變及熱循環(huán)應(yīng)力的作用下表面出現(xiàn)了大尺度的宏觀裂紋。
[Abstract]:Ni Co Cr Al YTa bonding layer was prepared on the substrate of nickel base superalloy by low temperature hypersonic plasma spraying (LT-HVOF). A 7w t y _ 2O _ 3-Zr _ 2o _ 2o _ 2o _ 7YSZ ceramic coating was prepared on the adhesive layer by atmospheric plasma spraying (APS). The diffusion and oxidation mechanism of the adhesive layer was studied on the basis of dynamic test, that is, thermal shock test. The sintering and phase transition process of the ceramic layer were discussed and the structure evolution of the coating was observed. The experimental results show that the dynamic thermal cycle increases with the increase of the number of thermal shock. The bonding layer component is diffused and oxidized to form thermal growth oxide (TGOO) and its thickness increases gradually. In addition, the bonding layer component diffuses along the internal crack of ceramic layer to the high temperature region under the temperature gradient. Finally, a large number of metal oxides appear in the cracked area of the ceramic layer, and the diffusion of the bonding elements is helpful to the sintering of the ceramic layer, which leads to the increase of the microhardness of the ceramic layer, and the bonding layer is due to the Kirkendall effect. The microhardness of the ceramic layer decreases gradually due to a large number of pores. In addition, large scale macroscopic cracks appear on the surface of the ceramic layer under the action of phase transformation and thermal cycling stress.
【作者單位】： 華南理工大學(xué)材料科學(xué)與工程學(xué)院;廣州有色金屬研究院現(xiàn)代材料表面工程技術(shù)國家工程實(shí)驗(yàn)室;廣州有色金屬研究院新材料研究所;
【基金】：國家“973”計(jì)劃項(xiàng)目(2012CB625100) 國家“863”計(jì)劃項(xiàng)目(2012AA03A512)~~
【分類號(hào)】：TG174.4

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 管恒榮,李美Y，

本文編號(hào)：1541704