注入稀土元素改善钢的耐蚀性

离子注入技术已超出了半导体工业的范围,成为材料科学中强有力的研究手段,并在材料改性领域中开始了工业应用。有人认为离子束技术是进行“材料设计”的手段,是实现“从天然材料到人造材料时代的关键。稀土元素在冶金中的应用很有前途,加入适量稀土可改善钢的机械性能、加工性能和耐蚀性能。但稀土元素改善钢的耐蚀性的作用和机理都有待深入研究,而用离子注入技术系统研究稀土元素改善钢的耐蚀性的工作尚未见报道。我国稀土资源丰富,系统地研究注入稀土元素的作用有重要意义。为了改善航空发动机轴承的抗局部腐蚀性能,美国海军实验室曾将Cr、Mo等常规耐蚀合金元素注入到轴承钢表层,并取得良好效果。本工作亦显示了注入稀土元素改善轴承钢抗点蚀特性的潜力。     

321不锈钢在低酸度硝酸铀酰溶液中的腐蚀特性

用称量法和电化学法研究了321不锈钢在不同浓度和pH值的硝酸铀酰溶液中的高温均匀腐蚀和电化学府蚀行为。均匀腐蚀试验结果表明．在选定的腐蚀条件下，321不锈钢样品在960h内，其表面光洁度无明显变化．腐蚀速率小于0．04mg/m^2.h，在低酸度的硝酸铀酰溶液中耐蚀。用腐蚀电入学法研究了321不锈钢在有溶解氧的硝酸铀酰溶液中的腐蚀电化学特性，测量了电极的腐蚀电位、腐蚀电流密度。经AES分析表明，电化学腐蚀后的样品在腐蚀膜中有一定量的铀．深度剖析含铀腐蚀膜的厚度为10—15nm。     

航空轴承表面改性的研究

本文介绍了采用离子注入的两种工艺路线(直接注入和离子束混合),对两种航空轴承材料(GCr15和Cr4Mo4V)经过单一元素或多元素组合的注入或混合处理后性能的影响。试验结果表明:两种工艺对两种材料表面改性的效果是相当的,都能大大提高材料表面抗腐蚀性能和耐磨性能。     

Formation of Nano-Crystalline Phase in Hydrogenated Amorphous Silicon Thin Film by Plasma Focus Ion Beam Irradiation

A 3.3 kJ Mather type dense plasma focus device is used to generate a pulsed argon ion beam of 100 KeV in this work. Hydrogenated amorphous silicon (a-Si:H) film prepared by plasma enhanced chemical vapor deposition (PECVD) on c-Si substrate was irradiated with the argon ion beam produced by this dense plasma focus device. The effects of exposure to a single, 5 and 10 shots of dense plasma focus argon ion beam irradiation on the surface morphology, crystallinity and chemical bonding properties of the a-Si:H films were studied using Field Emission Scanning Electron Microscope (FESEM), X-ray Diffraction (XRD), Raman scattering and Fourier Transform Infrared (FTIR) spectroscopy, respectively. Formation of nano-crystalline silicon phase along with increase in structural order and hydrogen content in the film structure has been observed when the a-Si:H film was irradiated with a single shot of dense plasma focus argon ion beam. Exposure to 5 and 10 shots of the dense plasma focus argon ion beam irradiation reduced the hydrogen content resulting in a decrease in crystallinity and structural order in the film structure.     

用~(14)N(d,α_1)~(12)C核反应研究注入氮在纯铁和GCr15钢中的深度分布

本文描述了利用~(14)N(d,a_1)~(12)C核反应测量固体样品表面层内氮原子含量及深度分布的方法。在Si_3N_4标准样品中,所得到的表面处的深度分辨为48nm。利用该分析手段,研究了在不同注入温度条件下,氮离子注入纯铁和GCr15钢的保留量及深度分布的变化情况。     

非晶Fe-Zr-B薄膜穆斯堡尔谱学研究

用X射线衍射分析、X射线光电子能谱(XPS)和穆斯堡尔谱学研究了直流磁控溅射法制备的Fe-Zr-B薄膜。X射线衍射分析结果表明制备态的薄膜是非晶的;X射线光电子能谱(XPS)结果表明样品表面氧化较明显,深层部分Fe, Zr, B结合占主导地位;穆斯堡尔谱学结果表明薄膜中Fe原子周围Zr、B原子的存在使Fe原子核内场值有所下降并导致超精细场分布P(H)出现双峰结构,薄膜中存在两种不同的局域微结构。     

Microstructure and mechanical properties of Fe alloys ion implanted with Ti and N

The microstructure resulting when Ti and N are both ion-implanted into pure Fe at room temperature has been examined with ion beam analysis, transmission electron microscopy, and electron energy loss spectroscopy. Precipitates of TiN form within the bcc Fe matrix, in contrast to the amorphous phase which forms when Ti and C are both implanted. For comparison, the microstructure resulting when N alone is implanted into Fe was also examined, and Fe₂N precipitates were observed within the Fe matrix. The surface mechanical properties of 15?5 PH steel which was implanted with both Ti and N were examined with pin-on-disc testing, and the results were interpreted in terms of the microstructures observed in Fe. The modifications produced by Ti + N implantation are the same as observed with other treatments producing hard nitrides or carbides within the iron-based matrix: reduced wear is observed, but not reduced friction.     

动态离子束混合技术制备氧化铬薄膜的X射线光电子能谱与俄歇电子能谱研究

本文介绍的动态离子束混合技术制备氧化铬薄膜系在不锈钢基体上进行1keV氩离子束溅射沉积铬(同时通入一定量的O),并用100 keV的氩离子束或氧离子束轰击该样品.对两种离子束轰击形成的氧化铬薄膜进行了X射线光电子能谱(X-ray photoelectron spectroscopy,XPS)和俄歇电子能谱(Auger electron spectroscopy,AES)的分析研究.发现Ar 离子束制备的氧化铬薄膜主要是Cr2O3化合物,而O 离子束制备的氧化铬薄膜含有其它价态的铬氧化物.Ar 离子束制备氧化铬薄膜的污染碳少于O 离子束制备.与O 离子束制备相比较,相同能量的Ar 离子束轰击更有利于提高沉积的Cr原子与周围O2的反应性;Ar 离子束制备的氧化铬薄膜过渡层的厚1/3左右,较厚的过渡层显示了制备的薄膜具有较好的附着力.     

Sputtering yields of 1 to 20 kev light ions on stainless steel

Sputtering yields for 1 to 20 keV H⁺, D⁺, He⁺, Ne⁺ and Ar⁺ ions on 304 stainless steel films have been measured. The films with a thickness of 0.1 to 1 μm were sputter deposited onto polycrystalline Be substrates. Rutherford backscattering of 2 MeV He⁺ ions was used for in situ measurement of the thickness of the stainless steel film. The sputtering yields were obtained from the slope of the decrease in film thickness with increasing sputtering ion dose. The measured yields agree well with yields obtained by weight loss in this laboratory, they are however lower than those published earlier.     

几种钢材离子注氮与氮化的磨损性能研究

本文对9Cr18、GCr15及Cr12MoV三种钢材在离子注氮、气体氮化、离子氮化以及淬火等不同工艺处理后,轻负荷下的抗磨损性能进行了研究。发现离子注氮后的试样抗磨损性能最佳,并随着形成氮化物元素的增加,抗磨损性能显著改善。用AES、XPS、TEM及X射线衍射法综合分析了注氮层的成分和结构。