注钼H13钢的抗磨损机理研究

利用MEVVA源(金属蒸汽真空弧离子源)引出的强束流脉冲钼离子对H13钢进行了不同束流密度的离子注入。加速电压是48kV,剂量为2×10~(17)cm~(-2),束流密度在25至68μA.cm~(-2)间。x衍射分析证明在注入层内可形成MO_2C相。磨损试验证明:注钼H13钢的磨损特性随着束流的变化而变化。最后指出了MEVVA源在材料表面改性方面的应用前景。     

Synthesis of Co-silicides and fabrication of microwave power device using MEVVA source implantation

Co synthesis silicides with good properties were prepared using MEVVA ion implantation with flux of 25-125μA/cm2 to does of 5×1017/cm2. The structure of the silicides was investigated using X-ray diffraction (XRD) and transmission electron microscopy (TEM). TEM analysis shows that if the ion dose is greater than 2×1017/cm2, a continuous silicide layer will be formed. The sheet resistance of Co silicide decreases with an increase in ion flux and ion dose. The formation of silicides with CoSi and CoSi2 are identified by XRD analysis. After annealing, the sheet resistance decreases further. A continuous silicide layer with a width of 90-133 nm is formed. The optimal implantation condition is that the ion flux and dose are 50μA/cm2 and 5×1017/cm2, respectively. The optimal annealing temperature and time are 900℃ and 10 s, respectively. The ohmic contact for power microwave transistors is fabricated using Co ion implantation technique for the first time. The emitter contact resistance and noise of the t     

C和W双注入H13钢的抗腐蚀机制研究

用多次扫描电位法研究了C和W双注入Hl3钢的抗腐蚀特性，用扫描电子显微镜(SEM)对改性机理进行了分析，还讨论了抗腐蚀增强机理。实验结果表明，经过30周期腐蚀后，H13钢表面出现了严重的腐蚀现象，表面上的腐蚀坑形状和排列具有晶态特征。C和W双注入H13钢经过50周期腐蚀后，发现表面仅出现了很轻微的腐蚀现象。当注量较低时，表面出现了小而浅的腐蚀坑，腐蚀坑的形状和排列没有出现晶态特征，说明抗腐蚀钝化层为非晶态结构，这种结构具有良好的抗腐蚀特性；当注量较大时，经过长达88周期腐蚀后，表面仍未出现腐蚀坑，说明抗腐蚀特性得到了进一步的提高。     

Nanometer structure and conductor mechanism of polymer modified by metal ion implantation

Polyethylene terephthalate (PET) has been modified by Ag, Ti, Cu and Si ion implantation with a dose ranging from 1 × 1016 to 2 × 1017 ions/cm2 using a metal vapor vacuum arc (MEVVA) source. The electrical properties of PET have been improved by metal ion implantation. The resistivity of implanted PET decreased obviously with an increase in ion dose. The results show that the conductive behavior of a metal ion implanted sample is different from Si-implantation samples. In order to un-derstant the mechanism of electrical conduction, the structures of implanted layer were observed in detail by XRD and TEM. The nano carbon particles were dispersed in implanted PET. The nano metallic particles were built up in metallic ion implanted layers with dose range from 1 × 1016 to 1 × 1017 ions/ cm2. The nanometer metal net structure was formed in implanted layer when a dose of 2 × 1017ions/ cm2 is reached. Anomalous fractal growths were observed. These surface structure changes revealed conducting mechanism evo     

双重离子注入钢表面钝化层的形成和抗腐蚀特性

利用金属离子与碳离子双注入可在金属表面形成陶瓷化的复合层,取得了抗腐蚀和抗磨损优良特性,研究了注入剂量和束流密度对这种复合层结构的影响,X射线分析结果表明,双注入可形成金属合金相和碳化物的钝化复合层,电化学测量和扫描电子显微镜观察表明,金属离子注入可明显地改善H13钢表面抗腐蚀特性,Mo C和Ti C双注入则此Mo和Ti单注入抗腐蚀和抗磨效果好得多,碳和金属离子双注入顺序对腐蚀特性也有明显的影响,研究表明,先注入碳后注入金属效果更好。随束流密度的增大,改性效果增强,注入后退火可形成陶瓷化的复合层,抗腐蚀效果进一步得到提高。     

C+Ti双离子注入H13钢抗腐蚀结构的分析

利用阳极化扫描方法测量了C＋Ti双离子高剂量注入H13钢样品在NaAc/HAc缓冲液（pH=5.6)中的耐腐蚀性能。结果表明,双离子注入明显地降低样品的峰值电流密度,改善样品的耐腐蚀性能;Ti离子的注入剂量越高,样品的耐腐蚀性能越好。在0.1mol/L NaCl溶液中点蚀实验结果表明,离子注入后样品的点蚀电位提高75mV,耐点蚀性能明显改善。TEM和SEM结果表明,注入样品的表面形成了一层晶粒细化层,从而减少了腐蚀坑的形核位置,阻止腐蚀的进一步进行,提高了样品的耐蚀性。     

离子束材料改性应用中的新进展

着重分析了离子注入提高离子束加工效益的途径，离子束工业生产发展现状和未来离子束技术在国民经济中的重要作用。     

V和C双注入钢纳米结构和抗磨损特性

介绍了V C双重离子注入钢的合成纳米结构、相交和抗磨损机制。研究表明，V C离子注入可使H13钢表面的硬度提高70％，摩擦系数下降52％，适合于工业应用。探索了改善H13钢表面摩擦学特性的新方法和途径，并探索了工业化应用前景。