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1.
采用磁过滤阴极真空弧(FCVA)技术,室温下通入C2H2在Si(100)与304不锈钢片上制备nc-ZrC/a-C:H复合薄膜.采用XRD、Raman、XPS、SEM-EDS研究了薄膜的成分及微观结构,利用纳米力学探针和摩擦磨损仪测试薄膜的硬度及摩擦磨损性能.主要讨论了不同C2H2气体流速对复合膜成分、结构及其性能的影响,研究结果表明:C2H2气体流速由20mL·min-1增加到70mL·min-1时,薄膜中的C原子分数逐渐升高;气体流速超过70mL·min-1后,C原子分数趋于平稳(约为75%).随着气体流速的增加,薄膜硬度呈现先增后减的趋势,当气体流速为40mL·min-1时(C原子分数约为65%),制备的薄膜综合机械性能达到最佳(硬度41.49GP,摩擦因数0.25).  相似文献   

2.
采用磁过滤阴极真空弧法,以C2H2和N2混合气体为反应气体在单晶硅上沉积纳米nc-ZrCN/a-C:H(N)复合膜, 用X射线衍射(XRD)、扫描电镜的能谱仪(SEM-EDS)和X射线电子能谱(XPS)研究了薄膜的成分和结构.实验结果表明薄膜结构是由ZrCN晶粒镶嵌在无定形碳和碳氮化合物基体中;膜中的化合键主要以Zr-C, C=C(sp2)和C-C(sp3)形式存在;随着混合气体流量的增加,薄膜的锆原子分数减小,而N和C的原子分数逐渐增大.  相似文献   

3.
采用磁过滤MEVVA源制备DLC膜的研究   总被引:1,自引:0,他引:1  
采用磁过滤MEVVA沉积技术以石墨为阴极在几种衬底表面(单晶硅、不锈钢和工具钢等)上制备高质量类金刚石(DLC)薄膜.实验结果表明,沉积能量对薄膜的sp3键含量的影响为先随能量的增加而增加,达到最大值后,再增加沉积能量含量反而下降.硬度测试结果表明,非晶金刚石薄膜具有极高的硬度,为70~78GPa,远远高于衬底材料的硬度值.对非晶金刚石薄膜的摩擦性能试验结果表明,非晶金刚石薄膜的摩擦因数为0.16~0.2,大大低于衬底材料.  相似文献   

4.
反应磁控溅射法制备的氟化类金刚石薄膜摩擦特性的研究   总被引:1,自引:0,他引:1  
以高纯石墨做靶、CHF3/Ar为源气体采用磁控溅射法在不同射频功率条件下制备了氟化类金刚石(F-DLC)薄膜.利用原子力显微镜、纳米压痕、拉曼光谱、红外光谱和摩擦磨损测试仪对薄膜的表面形貌、硬度、键态结构以及摩擦学性能作了具体分析.测试结果表明,制备的薄膜整体较均匀致密,表现出了良好的抗磨减摩性能.当射频功率为120W时,薄膜的摩擦因数低至0.41左右.AFM和纳米压痕显示,薄膜摩擦因数受表面粗糙度和硬度影响,但并非成单调对应关系.拉曼和红外透射光谱表明,随着功率的增加,薄膜中的芳香环比例增加,sp3杂化含量减小,结果显示,CF2反振动强度的减弱和C—C链中较少量H原子的键入都可能得到相对较低的薄膜摩擦因数.  相似文献   

5.
采用室温磁控溅射技术在镁合金(AZ91D)表面制备出SiC(碳化硅)薄膜,利用纳米压痕仪、摩擦磨损试验机对薄膜的纳米力学性能和膜基系统的摩擦磨损性能进行了研究.试验结果表明:此薄膜具有低纳米硬度(12.39 GPa)、低弹性模量(78.93 GPa)和高硬弹比(0.157);膜基系统具有好的摩擦磨损性能,在以氮化硅球为对磨件的室温干摩擦条件下磨损速率在10-5mm3·m-1·N-1级,摩擦系数约为0.248,薄膜未出现裂纹和剥落.分析表明,此膜基系统具有良好抗磨性能与其薄膜具有低的硬度和高的硬弹比、膜基系统具有好的弹性模量匹配是相一致的.SiC薄膜的低纳米硬度、低弹性模量系基材镁所致.  相似文献   

6.
采用高功率脉冲磁控溅射法在Si和高速钢基底上制备类石墨(Graphite-like carbon,GLC)非晶碳膜,研究了基底偏压对薄膜微观结构、机械性能和摩擦学性能的影响.结果表明:随着基底偏压的增大,GLC薄膜sp2键含量先减小后增大,在基底偏压为-100 V时达到最小值;薄膜的硬度和弹性模量先增大后减小,表面粗糙度先减小后增大;GLC薄膜的摩擦学性能与其机械性能和表面粗糙度密切相关,在基底偏压为-100 V时,薄膜的平均摩擦系数最小.  相似文献   

7.
采用磁控溅射技术在单晶Si基片上交替沉积CrN层、ZrYN层,制备不同厚度ZrYN层的CrN/ZrYN纳米多层膜。利用X射线衍射仪、扫描电子显微镜、透射电子显微镜、纳米压痕仪表征纳米多层膜的微观结构和力学性能。结果表明:随着ZrYN层厚度的增大,纳米多层膜中CrN相的结晶程度呈现出先上升后下降的趋势;纳米多层膜的硬度、弹性模量、韧性也呈现出先增大后减小的趋势;当ZrYN层厚度为0.9 nm时,纳米多层膜具有最高的硬度、弹性模量、韧性,分别为20.3 GPa、210.4 GPa、2.25 MPa·m1/2。上述结果表明,随着ZrYN层厚度的增大,纳米多层膜出现由晶态向非晶态转变,在非晶态下,能够获得良好的综合力学性能。  相似文献   

8.
实验研究了不同乙炔与氩气流量比R对脉冲等离子体增强化学气相沉积(PECVD)类金刚石薄膜的沉积速率、AFM形貌、膜基结合强度、纳米压痕硬度以及弹性模量的影响。结果表明:薄膜沉积速率随C_2H_2流量的增大而增大,在R为4:1时沉积速率达到最大0.8μm/h;不同气体流量比下薄膜的表面形貌均光滑致密,纳米硬度是316L不锈钢基体的3倍以上;R为3:1时,Raman光谱ID/IG值为最小,对应此流量比下的最高纳米硬度16.1GPa,且粗糙度最低,摩擦系数为0.206。  相似文献   

9.
利用等离子体增强化学气相沉积技术,在2024铝合金表面制备类金刚石(DLC)薄膜,以改善铝合金表面机械性能。利用拉曼光谱及红外光谱,对不同沉积偏压下制备DLC薄膜的成分及结构进行表征;利用摩擦磨损试验机、纳米压痕仪及台阶仪等,分别对不同沉积偏压下制备DLC薄膜的耐磨性、硬度、弹性模量及薄膜厚度进行检测,并探讨了沉积偏压对薄膜结构及性能的影响规律及影响机制。研究表明:随着沉积偏压增大(1 800~2 600 V),薄膜厚度、硬度及弹性模量均先增大后减小。当沉积偏压为2 400 V时,DLC薄膜厚度最厚,硬度及弹性模量最高。当沉积偏压为2 600 V时,薄膜的H/(Ef)最高,并且摩擦系数从基体的0.492降低至0.095 8。  相似文献   

10.
针对TiAlN薄膜耐磨性不够优异的问题,研究了Al质量分数对Ti_(1-x)Al_xN薄膜结构和摩擦学性能的影响。采用磁控溅射沉积技术制备了4种不同Al质量分数的Ti_(1-x)Al_xN薄膜。利用扫描电镜(SEM)、能谱仪(EDS)及X射线衍射仪(XRD),对薄膜的微观形貌、元素成分与晶体结构进行了表征。采用纳米压痕仪测试薄膜的硬度和弹性模量,用摩擦磨损试验机和白光干涉三维形貌仪测试薄膜的摩擦磨损性能。研究结果表明:随着Al质量分数在一定范围内的增加,薄膜从沿c-TiN(111)晶面生长逐渐转向h-AlN(200)晶面择优取向,Ti_(1-x)Al_xN薄膜疏松结构得到了改善,柱状结晶发生细化,表面形貌更加致密。同时,Ti_(1-x)Al_xN薄膜的硬度和弹性模量得到提高,磨损机理由严重的磨粒磨损、黏着磨损转变为轻微的磨粒磨损,平均体积磨损率降低。Ti_(0.67)Al_(0.33)N薄膜的综合性能最优,硬度和弹性模量分别为14.059 GPa和203.37 GPa,摩擦因数最低为0.182,平均体积磨损率为1.321×10~(-8) mm~3/(N·m),呈现出较好的摩擦学性能。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

14.
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   

15.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

16.
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.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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。  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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