摘要
目的研究了真空、大气2种环境下CrN涂层的热稳定性与氧化行为。方法采用反应磁控溅射技术在(100)取向的P型单晶硅基底上制备了CrN涂层。利用真空热脱附谱(TDS)、场发射扫描电子显微镜(FESEM)、拉曼光谱(Raman)、X射线衍射(XRD)和扫描电子显微镜(SEM)以及加装的能谱仪(EDS)等表征方法,研究了在不同温度下涂层的热稳定性与氧化行为。结果在真空退火时,TDS结果表明CrN涂层中的N在664℃左右开始释放,在温度达到1000℃时释放结束。而在温度高于900℃时释放速率和释放量开始迅速上升,在温度达到930℃时达到峰值。在加热过程中,涂层中的CrN相部分转变为Cr_(2)N相,在温度达到1000℃时,完全转变为CrSi_(2)相。在大气环境中,当温度达到700℃时,涂层开始被氧化,涂层表面生成了一层约136 nm厚的致密氧化层,同时在氧化层下方生成了一层CrOxN1‒x的过渡层,并且涂层也出现了Cr_(2)O_(3)的拉曼峰。当温度达到800℃时,Cr_(2)O_(3)氧化物拉曼峰和衍射峰的数量和强度显著增加,说明涂层表面生成的氧化物的结构由简单变为复杂,并且结晶性增强。此外,氧化物颗粒逐渐长大,氧化层厚度增加,在温度达到850℃时,氧化层厚度达到429 nm。当温度高于700℃时,CrN涂层沿着厚度方向的元素扩散行为是O元素的向内扩散和N、Cr元素的向外扩散,并且释放的N在氧化层下方富集,并没有释放出去。结论CrN涂层在真空中的热稳定性在900℃左右,在大气中的热稳定性在700℃左右。在大气中致密的Cr_(2)O_(3)氧化层的形成对O元素的向内扩散和N、Cr元素的向外扩散具有很好的阻挡作用。氧化层的这种阻挡作用对涂层的内部起到保护作用,延缓了涂层进一步的氧化和分解,这是CrN涂层热稳定性较好的原因。
In this work,the thermal stability and oxidation behavior of CrN coating were studied in vacuum and atmosphere.The composition and structure changes of CrN coating in different environments at high temperature were investigated.Then,the influence of such composition and structure changes on the performance of the coating was study.These results can provide experimental and theoretical basis for the development of multiple coatings with higher thermal stability in the future,and ultimately improve the performance of CrN coating at high temperature.The CrN coatings were prepared by reactive magnetron sputtering on(100)oriented P-type monocrystalline silicon substrate.The vacuum thermal desorption spectroscopy(TDS),field emission scanning electron microscopy(FESEM),Raman spectroscopy(Raman),X-ray diffraction(XRD),scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS)were used to characterize the thermal stability and oxidation behavior of the CrN coating at different temperatures.The release of N from CrN coating begins at about 664℃and that ends at about 1000℃.Once the temperature is higher than 900℃,the release rate of N increases rapidly and that increases to maximum when the temperature rises to 930℃.During the heating process,the crystal structure of the coating partially changes from CrN to Cr_(2)N.It should be noted that it completely transforms into CrSi_(2) phase when the temperature reaches 1000℃.The formation of CrSi_(2) can be attributed to the release of N,leading to the coating loose.Further,a lot of vacancies generates in the coating,which provide a diffusion channel for the element of Si in the substrate.Thus,the Si in the substrate diffuses to the inside of the coating under the thermal driving effect,and forms a CrSi_(2) phase by bonding with Cr in the coating.In the atmosphere,the coating begins to oxidize when the temperature increases to 700℃,and a dense oxide layer with a thickness of 136 nm is formed on the coating surface.Besides,a transition layer of CrOxN1‒x
作者
金玉花
程融
柴利强
张学希
王鹏
JIN Yu-hua;CHENG Rong;CHAI Li-qiang;ZHANG Xue-xi;WANG Peng(State Key Laboratory of Advanced Processing and Reuse of Non-ferrous Metals Jointly Established by the Ministry and Province,Lanzhou University of Technology,Lanzhou 730050,China;State Key Laboratory of Solid Lubrication,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Lanzhou 730000,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2022年第12期82-90,108,共10页
Surface Technology
基金
国家自然科学基金(51865028)
国家自然科学基金青年项目(52005483)。
关键词
CRN涂层
反应磁控溅射
热稳定性
氧化行为
释放
扩散阻挡
CrN coating
reactive magnetron sputtering
thermal stability
oxidation behavior
release
diffusion barrier
