纯钛离子氮化层在人工唾液中的耐蚀性

用浸泡法和电化学法研究了纯钛(TA2)基体材料及其离子氮化层在人工唾液中的腐蚀行为.浸泡法研究表明,试样随着浸泡时间的延长而增重,而离子氮化层增重明显减缓,其腐蚀速率远小于TA2基材;电化学法研究表明,离子氮化层的自腐蚀电位较TA2基材提高,而腐蚀电流密度和腐蚀速度减小.由失重法和电化学法得出一致结论,离子氮化处理提高了TA2在人工唾液中的耐蚀性.     

空心阴极烧结粉末冶金制品工艺研究

为了克服常现粉末冶金制品烧结工艺的缺点，试验研究了空心阴极等离子烧结工艺。介绍了空心阴极烧结装置、烧结方法、空心阴极功率输出特性和应用实例。     

硫对Inconel718高温合金组织性能的影响

对不同硫含量的４炉Ｉｎｃｏｎｅｌ７１８合金进行力学性能测试及显微组织分析结果表明，硫具有严重的危害作用，表现在试样最终热处理后的６５０℃持久寿命和塑性的恶化和６５０℃高温拉伸塑性的降低。     

纯钛Mo-N共渗改性层在H2SO4溶液中的腐蚀行为研究

采用等离子表面合金化技术对纯钛进行Mo—N共渗。利用电化学腐蚀系统对改性层及基体在0．5mol／L的H2S04溶液中进行电化学对比实验。实验结果表明，纯钛表面Mo—N共渗可以得到致密、均匀的表面改性层，改性层由沉积层和扩散层组成，厚度为4μm；改性层表面由钼氮化合物Mo16N7组成；Mo—N改性层提高了纯钛在0．5mol／L的H2SO4溶液中的耐蚀性，并对改性层在稀硫酸介质中腐蚀机理进行了初步探讨。     

轰击能量对离子束辅助磁控溅射沉积Cr-N薄膜断裂韧性的影响

应用低能离子束辅助磁控溅射技术(IBAMS)沉积Cr-N薄膜,用场发射扫描电镜(FESEM)、原子力显微镜(AFM)和X射线衍射表征薄膜的组织结构,讨论了轰击能量对Cr-N薄膜组织、晶粒度以及硬度和断裂韧性的影响.结果表明:随离子束辅助轰击能量的升高,Cr-N薄膜由粗大的柱状晶变为细小的晶粒,当轰击能量达到1 200 V时,薄膜呈现等轴晶结构,薄膜致密度增加.FESEM得到的表面颗粒尺寸和AFM得到的粗糙度随轰击能量升高呈现相同的变化趋势,这些表观大颗粒是由许多小的亚晶块聚集而成.进一步用X射线衍射谱形分析表明:随轰击能量从0 V升高到800 V时,亚晶块的尺寸逐渐减小;到800 V时,晶块尺寸约为9 nm,但当能量升到1 200 V时,晶块尺寸反而增大,这是由离子束辅助轰击导致的两种不同机制而引起的,一种是离子轰击导致的喷丸碎化作用,而另一种为热效应引起的晶粒长大;当轰击能量从0 V增加800 V时,薄膜的硬度和断裂韧性都显著提高,与晶粒度的减小有关;而到1 200 V时,晶粒度较未辅助略大,但却具有很高的硬度以及较高的断裂韧性,说明硬度和断裂韧性的提高还与离子束轰击导致薄膜的致密化增加有关.     

表面冶金高速钢组织的研究

研究了20钢经辉光离子W-Mo共渗,再经渗碳后,形成的表面冶金高速钢组织,并测试了淬火、回火后的硬度及红硬性,结果表明,此种表面冶金高速钢无碳化物偏析,其硬度及红硬性基本达到M2高速钢水平。     

Plasma boronizing of Ti6AlV4 using solid precursors by double glow plasma alloying technique

Solid state B-offerings （FeB compound） were used for plasma-assisted boronizing on Ti6Al4V alloy by double glow discharge plasma alloying technique （DGPSA）. During all experiment processing there was no harmful and toxic. The thickness and morphology, phase formation, elements concentrations and wear properties of boride layers were examined by means of optical microscopy, Vickers microhardness, X-ray diffraction, glow discharge optical emission spectroscopy and Ball-disk wear tests. The results show that friction coefficient of boride alloying samples versus cortmdum ball is lower than that of Ti6Al4V samples, as well as wear rate. This indicates that plasma-assisted boronizing of Ti6Al4V alloy has a high potential for industrial applications under tribological conditions.     

Surface alloying of Cu with Ti by double glow discharge process

The surface of pure copper alloyed with Ti using double glow discharge process was investigated. The morphology, structure and forming mechanism of the Cu-Ti alloying layer were analyzed. The microhardness and wear resistance of the Cu-Ti alloying layer were measured, and compared with those of pure copper. The results in-dicate that the surface of copper activated by Ar and Ti ions bombardment is favorable to absorption and diffusion of Ti element. In current experimental temperature, as the Ti content increases, the liquid phase occurs between the deposited layer and diffused layer, which makes the Ti ions and atoms easy to dissolve and the thickness of Cu-Ti al-loying layer increase rapidly. After cooling, the structure of the alloying layer is composed of CuTi, Cu4Ti and Cu(Ti) solid solution. The solid solution strengthening and precipitation strengthening effects of Ti result in high surface hardness and wear resistance.     

无氢等离子氮化纯钛降低细菌黏附的研究

纯钛在双层辉光放电等离子体条件下进行无氢氮化处理，表面得到一层均匀、致密的改性层。经过改性层的显微组织观察，硬度测量，元素分布情况测定，X射线衍射分析改性层结构，处理前、后表面细菌黏附等的分析和表征，发现纯钛表面经等离子氮化得到的氮化膜层最外层中包括Ti2N及TiN的2种氮化物，近表面过渡层是氮在a—Ti中的固溶体。与改性前相比，等离子氮化处理的纯钛表面能显著地降低细菌黏附。     

Corrosion resistance of Molybdenum Nitride modified Ti6Al4V alloy in HCl solution

The Mo-N surface modified layer on Ti6Al4V alloy was obtained by the plasma surface alloying technique. The structure and composition of the Mo-N modified Ti6Al4V alloy were investigated by X-ray diffraction （XRD） and glow discharge optical emission spectroscopy （GDOES）. The Mo-N modified layer contains Mo-N coating on subsurface and diffusion layers between the subsurface and substrate. The X- ray diffraction analysis of the Mo-N modified Ti6Al4V alloy reveals that the outmost surface of the Mo-N modified Ti6Al4V alloy is composed of phase Mo2N （fcc） and Mo2N （tetr）. The electrochemical corrosion performance of the Mo-N modified Ti6Al4V alloy in 0.5 mol/L HCl solution was investigated and compared with that of Ti6Al4V alloy. The chemical corrosion performance of the Mo-N modified Ti6Al4V alloy in boiling 37% HCl solution was investigated and compared with that of Ti6Al4V alloy. Results indicate that self-corroding electric potentials and corrosion-rate of the Mo-N modified Ti6Al4V alloy are higher than that of Ti6Al4V alloy in 0.5 mol/L HCl solution. The corrosion-rate of the Mo-N modified Ti6Al4V alloy is lower than that of Ti6Al4V alloy in boiling 37% HCl solution.