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1.
等离子化学气相沉积硬膜技术研究   总被引:3,自引:2,他引:1  
用等离子体化学气相沉积(PCVD)技术制备了TiN、TiC、Ti(CN)和(TiSi)N膜及其组合的多层膜。PCVD具有很好的覆盖性,PCVD-TiN具有很好的耐磨、蚀性,膜与基体结合良好,因而用PCVD法在高速钢刀具、模具及轴承上沉积TiN可大大提高其使用寿命。PCVD-TiN和Ti(CN)膜无明显柱状晶,其显微硬度高于TiN亦可用于高速钢刀具、模具上提高其使用寿命。PCVD-(TiSi)N,晶  相似文献   

2.
采用电子束蒸发的方法在抛光的200℃AlN陶瓷衬底上淀积厚度为200nm的Ti膜,并在高真空中退火.利用二次离子质谱(SIMS)、卢瑟福背散射谱(RBS)、俄歇电子能谱(AES)和X射线衍射分析(XRD)技术,研究了从200~850℃温区内Ti与AlN的固相界面反应,给出了界面组分分布随退火温度和时间的变化关系.在界面区发现了三元铝化物并观测到铝化物产生与发展过程.指出铝化物由Ti-Al二元和Ti-Al-N三元化合物组成.最后利用热力学理论对实验结果进行了解释  相似文献   

3.
以硬质合金作为衬底,分别采用了化学涂层(CVD)和物理化学涂层(PCVD)的技术涂复Ti(C,N)-TiN硬质膜,应用X射线光电子谱分析(XPS)技术,研究涂层表面化学成分、元素化学状态、物相组成及其随深度的变化。涂层表面由Ti,N,C,O和Co组成;表面物相包括TiN,TiO_x及CoO.随着深度的增加,Ti:N迅速变为1,而TiO_x和CoO含量急剧减少.  相似文献   

4.
采用离子束增强沉积方法(IBED),在Fe基上制备了TiN薄膜。通过划痕仪,透射电镜(TEM),俄歇电子能谱(AES),粘着力测量仪的观测,分析和计算,给出了膜的形貌,组分和机械特性;发现TiN膜与衬底之间存在一过渡区,膜中含氧量比气相真空沉积(CVD)明显减小。在AES定量计算中,本文采用一种与文献不同的方法,较为简便地处理了俄歇谱中Ti和N峰的重叠现象  相似文献   

5.
用离子束辅助沉积技术在GCr15钢基体上形成了TiCxNy膜.TEM观察揭示,膜呈多晶结构,具有(111),(200)和(220)择优取向.AES和XPS分析进一步证实,TiCxNy膜呈含氧配置.膜的硬度和摩擦特性与N含量有关,N的过高含量对提高表面硬度不明显,但摩擦特性明显下降.在作者的实验条件下,以3×1017/cm2的注量为宜.干摩擦表明,膜的抗氧化性能优良.不仅存在能有效地抑制基体在摩擦过程中形成的氧化皮,又由于硬度高,润滑性良好,还能显著地改善基体的耐磨粒磨损特性.  相似文献   

6.
工模具钢离子束混合改性层的组织结构与性能   总被引:1,自引:1,他引:0  
研究了M2钢表面TiN涂层的组织结构和性能。这种涂层是通过真空沉 积Ti原子和注入N离子交替进行的离子束混合技术实现的。每次沉积Ti原 子厚度1000~4000A,注入N离子能量60和90keV,剂量2×1017~8×1017 N+/cm2.分析讨论了改性层的相组成及其强化机制。结果表明,在适宜工艺 下,改性层具有高硬度、高耐磨性和优良的结合力。  相似文献   

7.
Al_2O_3 弥散 Ti(C,N)基金属陶瓷刀具   总被引:1,自引:0,他引:1  
在Ti(C,N)基金属陶瓷中,通过加入Al2O3弥散颗粒,使材料的硬度和高温性能都得到提高,从而获得更好的切削耐磨性。研究结果表明:Al2O3的引入使Ti(C,N)基金属陶瓷的常温强度和韧性有所下降而硬度和高温力学性能得到了改善。切削试验表明:Ti(C,N)-Al2O3系金属陶瓷比硬质合金、Al2O3-TiC复合陶瓷刀具有更好的切削性能。SEM观察表明:在Ti(C,N)-Al2O3金属陶瓷中,Al2O3与Ti(C,N)有相互抑制晶粒生长的作用,使Ti(C,N)基金属陶瓷的晶粒更细化  相似文献   

8.
用多弧离子法在高速钢(W18Cr4V)基底上沉积了Ti(N,C)薄膜,并运用SEM、XRD、XPS对该膜微观结构随进气流量r=G2H2/N2变化的情况进行了测试和分析。结果表明薄膜随r增加趋于致密,在r值较小时呈现较强的(111)择优取向,随着r值增大,(111)是这一取向逐渐变弱,(220)取向渐强,薄膜呈现典型耐心立方结构,主要万分为复合相Ti(n,C)膜含有少量石墨相成分存在。  相似文献   

9.
采用多束动态混合法在304不锈钢样品表面成功地制备出PTFE(聚四氟乙烯)和PEEK(聚醚醚酮)混合的高性能高分子复合膜,共结合力约70N,耐蚀能力提高20倍,摩擦系数达到0.07 ̄0.14,比授能吸收剂量在于10^6Gy。  相似文献   

10.
等离子炉碳(氮)化处理高钛高炉渣   总被引:7,自引:0,他引:7  
用氮等离子体对高钛渣进行碳(氮)化处理,在1700℃下停留1h,可使渣中钛的碳(氮)化转化率达92%,大于20μm的Ti(C,N)晶粒约40%,用重选方法选别碳化渣可得到含Ti(C,N)50%以上精矿,钛的回收率可达90%以上。  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

15.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

16.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

17.
18.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

19.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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