The influence of SixCy and SixNy amorphous coatings on the oxidation resistance of a Ti6242 (Ti–6Al–2Sn–4Zr–2Mo) alloy was investigated. They were produced at room temperature by the dynamic ion mixing technique combining physical vapour deposition with simultaneous bombardment with 120 keV Ar+ ions. Isothermal oxidation tests were carried out at 600 °C in 1 atm flowing synthetic air (80% N2, 20% O2) demonstrating a considerable reduction (not, vert, similartwo orders of magnitude) of the oxidation rate for at least 100 h. The structural modifications after oxidation were investigated by XPS, XRD, SEM, SIMS. The formation of SiO2 is detected as the main oxidation product in the coating and the formation of Ti–Si compounds is also observed in the coating/substrate interface region. The crystallisation of SixNy is not detected and for SixCy only some traces of β-SiC could exist. The improvement of oxidation resistance of Ti6242 is discussed in relation with the intrinsic properties of the coatings and with the interface mixing and ion beam densification.
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机译：研究了SixCy和SixNy非晶态涂层对Ti6242（Ti–6Al–2Sn–4Zr–2Mo）合金的抗氧化性的影响。它们是通过动态离子混合技术在室温下生产的，该技术将物理气相沉积与同时轰击120 keV Ar +离子相结合。等温氧化试验是在600℃，1个大气压流动的合成空气（80％N2、20％O2）中进行的，证明氧化速率至少降低了100个小时（不是垂直的，相似的两个数量级）。通过XPS，XRD，SEM，SIMS研究了氧化后的结构修饰。 SiO 2的形成被检测为涂层中的主要氧化产物，并且在涂层/基体界面区域也观察到Ti-Si化合物的形成。未检测到SixNy的结晶，对于SixCy，仅可能存在一些痕量的β-SiC。讨论了Ti6242的抗氧化性的改善与涂层的固有性能以及界面混合和离子束致密化的关系。
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