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采用热重分析对纯镍及其表面离子注钇样品在900℃空气中的恒温氧化动力学规律进行了研究.用扫描电子显微镜和透射电子显微镜对含钇和不含钇氧化膜的微观形貌及结构进行了观测.用声发射方法对氧化膜在恒温生长阶段和空冷阶段的开裂与剥落进行了实时监测,根据相应的氧化膜开裂模型,对声发射信号在时域和数域上的分布情况进行了分析.结果表明离子注钇显著降低了镍的恒温氧化速率,提高了表面NiO膜的抗开裂和抗剥落性能.离子注钇提高镍抗氧化性能的原因主要是钇细化了表面NiO膜的晶粒、提高了氧化膜的高温塑性和蠕变能力,并显著降低了Ni/NiO界面缺陷的数量和大小.
The thermo-gravimetric analysis was used to study the isothermal oxidation kinetics of pure nickel and its ion-implanted yttrium samples at 900 ℃ in air.The microstructure of yttrium-containing and yttrium-free oxide films was characterized by scanning electron microscopy (SEM) and transmission electron microscopy And structure were observed.The crack and spalling of the oxide film during the constant temperature growth stage and the air cooling stage were monitored by acoustic emission method. According to the corresponding oxide film cracking model, the distribution of the acoustic emission signal in the time domain and the number domain The results show that the ion implantation yttrium significantly reduces the constant temperature oxidation rate of nickel and improves the anti-cracking and anti-spalling properties of the surface NiO film.It is mainly due to yttrium refining surface NiO The grain of the film improves the high temperature plasticity and creep ability of the oxide film and significantly reduces the number and size of Ni / NiO interface defects.