渗硼预处理对硬质合金金刚石涂层刀具的影响研究

研究了渗硼预处理对硬质合金YG6刀具上金刚石涂层形核、生长和切削性能的影响.采用扫描电镜观察分析表面形貌,X-射线衍射进行物相分析,切削实验来考察刀具的切削性能.研究结果表明,渗硼预处理使硬质合金表面形成了CoB和Co2B,较好地抑制了Co对沉积金刚石的不利影响,金刚石涂层形核致密,硬质合金金刚石涂层刀具经渗硼预处理后在切削性能上略好于酸浸预处理的.     

强直电流伸展弧CVD硬质合金金刚石涂层工具

采用自行研制的强电流直流扩展电弧设备对酸浸和渗硼预处理的YG6刀片进行了金刚石薄膜涂层沉积，并对放于不同位置的沉积刀片表面涂层的激光Raman谱和SEM形貌进行了分析、研究。结果表明：渗硼预处理工艺优于酸浸预处理工艺；在渗硼处理的GY6刀片上，沉积的金刚石薄膜涂层具有大面积、均匀性好和质量高的特点。     

WC—Co硬质合金刀片热丝法金刚石薄膜涂层附着力

用热丝法研究了ＷＣ－６％Ｃｏ硬质合金刀片金刚石薄膜涂层附着力。结果表明：采用温度为８０℃,（ＨＣｌ：ＨＮＯ３：Ｈ２Ｏ）（体积比）为１∶１∶１溶液对硬质合金刀片表面去Ｃｏ１５ｍｉｎ后,经４０ｕｍ金刚石粉及１．５ｕｍ金刚石加２０ｕｍＴａＣ混合粉进行超声预处理,结果表明,沉积的金刚石薄膜与硬质合金刀片基底具有良好的附着力,而经４０ｕｍ金刚石粉处理的薄膜涂层组织与附着力要好一些。     

稀土硬质合金刀片切削性能

通过切削性能对比试验证实，研制的稀土硬质合金刀片ＹＴ８ＲＥ及ＹＧ６ＲＥ的切削性能，分别比普通硬质合金刀片ＹＴ１５及ＹＧ６优越。以ＹＴ８ＲＥ及ＹＴ１５刀具切削４５钢时，前者与者相比，切屑变形系数降低８％，切削力约下降７．５％，刀具耐用度提高２０％以上。以ＹＧ６ＲＥ及ＹＧ６刀具加工冷硬铸铁时，前者比后者切削力降低约６％，刀具耐用度平均提高４８％以上。     

自保护硼氮共渗膏剂的研究

为研究自配制的自保护硼氮共渗膏剂的性能，对Q235钢、45钢、T8钢和GCrl5钢等试样进行共渗试验。实验表明，45钢以选用890C共渗为宜；钢中的碳阻碍硼的渗入；涂层厚度以4mm为宜；膏剂硼氮共渗试样的耐磨性与固体硼氮复合渗相当，而比固体渗硼试样则好得多；经膏剂硼氮共渗的试样耐100％HCl和30％H2SO4的腐蚀性与固体硼氮复合渗处理过的试样相当，二者均比1Crl8Ni9Ti钢要好；Q235钢高温缓冷后易出现Fe3N相。表明该膏剂共渗性能与固体硼氮相当，而优于固体渗硼。     

金刚石涂层木工刀具的研究

采用热丝加热化学气相沉积法，将金刚石薄膜涂覆硬质合金刀片，在杠杆式磨损实验台进行磨损试验。结果表明，涂层刀片的磨损量降低了６０％，薄膜剥离是造成金刚石涂层没有大幅度提高刀片耐磨性的根本原因。     

CVD金刚石涂层硬质合金工具表面预处理新技术

研究了利用(KOH K3(Fe(CN)6) H2O和H2SO4 H2O2)两种溶液浸蚀硬质合金基体，分别选择性刻蚀WC和Co的表面预处理过程．在浸蚀过的硬质合金基体上，用强电流直流伸展电弧等离子体CVD法沉积金刚石薄膜涂层．结果表明，两步混合处理法不仅可以有效地去除硬质合金基体表面的钴，而且还显著粗化硬质合金基体表面，提高了金刚石薄膜的质量和涂层的附着力．     

金刚石涂层用硬质合金基体表面预处理方法的研究

本文分析和综述了影响金刚石涂层与硬质合金基体粘结性的主要因素。按照其原理来分,预处理方法可分为物理预处理法、化学预处理法以及中间层法。通过适当的预处理能有效消除或抑制基体中钴粘结相的负面影响,提高金刚石涂层与硬质合金基体间的粘结强度。     

掺硼金刚石薄膜涂层刀具的制备及试验研究

采用偏压增强热丝化学气相沉积法,以硼酸三甲酯为掺杂源,以WC-Co硬质合金刀具为衬底,制备了不同掺硼浓度的金刚石薄膜涂层刀具.通过采用扫描电子显微镜(SEM)、拉曼光谱及压痕测试对涂层刀具的表面形貌、薄膜质量和膜-基附着力进行了研究,分析了硼元素对薄膜质量和刀具性能的影响.研究结果表明:硼掺杂可以有效抑制刀具表层钴的扩散,改变金刚石薄膜的成分;掺硼金刚石薄膜的晶粒取向主要是{111},随着掺硼浓度的增加,金刚石薄膜的晶粒变小,平均晶粒尺寸从10 μm下降到2 μm;金刚石薄膜的拉曼光谱中心声子线随着掺硼浓度的增加向低频方向漂移,强度降低,且出现多晶石墨峰;涂层的膜-基附着力在硼碳摩尔比B/C=3×10-3时最佳.通过对碳化硅颗粒增强铝基复合材料的切削加工试验表明,在适当的掺硼浓度下金刚石薄膜涂层刀具的切削性能得到了显著改善.     

涂层硬质合金刀具切削韧性研究

切削韧性和耐磨性是刀具材料发展中的一对主要矛盾。目前涂层硬质合金刀片的耐磨性大大优于非涂层基体硬质合金刀片,而切削韧性却有所下降。不同的涂层厚度,不同的涂层材料和不同的基体材料对涂层刀片切削韧性的影响程度亦有所不同。 本文从探讨涂层刀片的破损机理入手,分析了涂层刀片切削韧性下降的原因;推导了涂层刀片表面残余应力σ_R的计算公式;提出了基体材料必须具备较高的断裂韧性K_(1c),进而寻求提高涂层刀片切削韧性的途径;并用断裂力学理论定量试算了最佳涂层厚度。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that