Y对CrAlN膜层结构及高温抗氧化性能的影响

发布时间：2018-03-05 13:18

  本文选题：CrAlYN薄膜　切入点：CrAlSiN薄膜　出处：《沈阳理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：CrAlN薄膜因为具有高硬度、良好的耐磨性能以及优异的高温抗氧化等性能,得到了广泛的关注,并已经成功应用在了刀具、模具、航空等许多领域。但是随着科技的发展,对膜层的性能要求也变得越来越高。本论文主要研究Y、Si元素的加入对CrAlN薄膜性能的影响。采用磁控溅射技术,在高速钢基材上沉积不同Y含量的CrAlYN薄膜,不同Si含量的CrAlSiN薄膜以及CrAlSiYN薄膜,并进行了大气和真空高温热处理实验。通过SEM、EDS、XRD以及纳米压痕仪等设备对薄膜元素组成、纳米硬度、弹性模量以及热处理前后的表面形貌和物相结构进行了表征。分别研究了Y、Si元素对薄膜硬度、弹性模量、物相组成、高温抗氧化性能以及热稳定性能的影响。加入Y后薄膜没有新的物相形成,但是(Cr,Al)N相的衍射峰取向由(200)向(111)转变。与CrAlN膜层相比,CrAlYN薄膜Y含量为0.41at.%时膜层的硬度、弹性模量和高温抗氧化性能显著改善,Y含量2.75at.%和3.94at.%时,膜层的综合性能有所降低。大气高温热处理后的CrAlYN膜层,O、Cr、Al、Fe和Y等元素均在晶内均匀析出,但是在晶界和岛状大颗粒处,O富集而贫Al和贫Fe。CrAlSiN薄膜,硬度模量在Si含量为7.18at.%时,相对较优。CrAlSiN薄膜,800℃没有氧化痕迹,抗氧化性能良好。900℃,出现Cr2O3和Al2O3氧化物,膜层发生氧化。1000℃膜层隆起,膜层与基体结合力减弱,存在大量的Fe2O3相和少量的Cr3O相,氧化严重。利用Cr30Al70合金靶制备的CrAlSiYN薄膜的硬度模量远低于CrAlSiN和CrAlYN薄膜,利用Cr50Al50合金靶制备的CrAlSiYN薄膜的硬度模量相比于利用Cr30Al70靶制备的CrAlSiYN薄膜有了很大提高,但是与CrAlSiN和CrAlYN膜层相比,硬度模量并没有得到明显改善。CrAlSiYN薄膜的高温抗氧化性能也没有提升,1000℃时,已经完全氧化失效。经850℃真空热处理后,热稳定性能良好,真空热处理温度升高到950和1050℃时,薄膜表面出现网状裂纹。1050℃时膜层表面呈现出沙粒状向外鼓出的形貌。
[Abstract]:Because of its high hardness, good wear resistance and excellent high temperature oxidation resistance, CrAlN thin film has been widely concerned, and has been successfully applied in many fields, such as cutting tools, mould, aviation and so on. But with the development of science and technology, In this paper, the effect of the addition of Y Si on the properties of CrAlN thin films was studied. The CrAlYN films with different Y content were deposited on high speed steel substrates by magnetron sputtering. CrAlSiN films and CrAlSiYN thin films with different Si content were subjected to high temperature heat treatment in atmosphere and vacuum. The elastic modulus, surface morphology and phase structure of the films before and after heat treatment were characterized. The effect of high temperature oxidation resistance and thermal stability. There was no new phase formation after adding Y, but the diffraction peak orientation of CrAlN phase changed from 200 to 111). The hardness of CrAlYN film was 0.41at.wt% compared with that of CrAlN film. When the modulus of elasticity and oxidation resistance at high temperature improved 2.75at.% and 3.94at.%, the comprehensive properties of the CrAlYN film decreased. After high temperature heat treatment in atmosphere, the elements of CrAlYN film, such as OU, Cr, Al, Fe and Y, were precipitated homogeneously in the crystal. However, when the hardness modulus of Al and Fe.CrAlSiN thin films is 7.18at.wt%, there is no trace of oxidation at 800 鈩，

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