Cr,Ni的掺杂对TiAlN基薄膜高温摩擦性能的影响

为了开发具有优异抗摩擦磨损性能的薄膜材料,采用多弧离子镀在4Cr13马氏体不锈钢表面沉积TiAlN薄膜,采用磁控溅射法和多弧离子镀在4Cr13表面分别沉积掺杂Cr和Cr-Ni的TiAlN薄膜.采用扫描电镜(SEM)、X射线衍射仪(XRD)和维氏硬度计分析薄膜的表面形貌、物相和表面硬度,并对不同温度下磨损后的薄膜表面形貌...     

直流磁控溅射制备(Ti,Al)N薄膜研究

本研究采用直流磁控溅射的方法在W 18Cr4V高速钢基体上制备不同Al/Ti比例的(Ti,Al)N薄膜,为此,在圆柱形磁控溅射Ti靶表面上,采用多弧离子镀技术覆盖不同面积和一定厚度的纯Al,结果表明:只有在靶材的外表面Ti与Al的交界附近的样品才能沉积成薄膜,随着靶材表面覆盖纯A l的面积增大,所形成的结晶薄膜中的Al/Ti比例增大,膜层中的相组成AlN的数量增多,而TiAlN的数量减少,此外纯Al的覆盖面积过大,将导致溅射时所需要的气压过高而无法沉积成膜。     

脉冲偏压占空比对复合离子镀(Cr,Al)N薄膜结构和力学性能的影响

采用将电弧离子镀与磁控溅射离子镀相结合而得的复合离子镀的方法,分别用高纯Cr作为电弧靶、用高纯Al作为溅射靶,通入氮气和氩气,在高速钢和硅片上沉积(Cr,Al)N薄膜。通过台阶仪、扫描电镜、X射线衍射仪、维氏硬度计等分析和测量手段,研究了不同脉冲偏压占空比条件下(Cr,Al)N薄膜结构和力学性能的变化规律。研究表明,占空比对薄膜的结构和力学性能均有影响,当占空比为40%时,薄膜的沉积速率最大,为12.8 nm/min,用25 g载荷保荷10 s测试的维氏硬度1725 Hv也为实验获得的最大值。     

占空比对磁控溅射纯Cr镀层微观组织结构的影响

利用磁控溅射离子镀技术于不同占空比下在单晶Si基体上制备出纯Cr镀层,采用扫描电子显微镜和X射线衍射仪分析了纯Cr镀层表面和截面微观形貌、沉积速率和择优生长取向的变化规律。结果表明:占空比的改变显著影响着纯Cr镀层的微观形貌、择优生长取向和致密度。随着占空比的增大,纯Cr镀层的微观组织结构由柱状晶向均匀、细小纳米晶转变,纯Cr镀层的厚度和沉积速率相应增大,同时纯Cr镀层沿(110)晶面的择优生长取向程度减弱。     

脉冲电压对HPPMS制备CrN薄膜的组织结构与力学性能的影响

采用复合高功率脉冲磁控溅射技术在单晶Si片、高速钢和玻璃上制备CrN薄膜。分别研究了脉冲电压在500,600,700,750 V时对薄膜的组织结构和力学性能的影响。结果表明,随着脉冲电压的增加,靶材离化率增加,靶电流以及溅射原子离子数量级能量均增大,使得沉积的薄膜组织结构更加致密,晶粒逐渐细化,表面更加光滑,硬度提高。高功率脉冲磁控溅射技术具备了磁控溅射技术制备的薄膜表面光滑优势,以及电弧离子镀高离化率特点,获得了结构性能优异的CrN薄膜。     

真空离子镀膜经验讲习班公告

<正>讲课内容:真空基础知识、薄膜沉积技术、离子镀膜机结构、离子镀膜一般工艺制订、离子镀代替电镀、离子镀超硬涂层、磁控溅射新     

Cr及Cr-Ni掺杂对不同偏压下TiAlN薄膜性能的影响

为了使4Cr13不锈钢表面性能得到更好的优化和获得镀膜最佳的偏压工艺,在不同的偏压工艺下,采用多弧离子镀技术和磁控溅射技术在4Cr13不锈钢表面沉积掺杂Cr和同时掺杂Cr、Ni的TiAlN薄膜.采用附着力自动划痕仪研究不同偏压条件下薄膜与基体的结合力,采用扫描电子显微镜观察和分析薄膜的表面形貌,采用XRD技术检测薄膜的相结构,采用显微硬度计测量薄膜的显微硬度.结果表明:适当的偏压可以提高薄膜的硬度和结合力,在偏压为-250 V时,薄膜的表面硬度达到最大值2 259 HV0.1 N,结合力为36 N;并且掺杂Ni元素能够起到增强膜基结合力的效果.     

中频磁控溅射技术制备Co-Ni合金薄膜

由于电镀硬铬对环境有一定的污染,因而选择合适的制备方式和合适的替代硬铬的材料具有一定的实际意义。本文选用Co-Ni作为硬铬的替代材料,并采用中频磁控溅射的方式在铜基底上制备Co-Ni合金薄膜,重点研究了溅射功率与Co-Ni合金薄膜的沉积速率、成分的关系,结果表明沉积速率随溅射功率的增加而增加;溅射功率在0.8~1.1 kW之间时,薄膜成分与靶材成分基本一致;并把1.1 kW时制备的Co-Ni合金薄膜的电极化腐蚀性能与电镀Cr薄膜、离子镀Cr薄膜相比较,结果表明Co-Ni合金的腐蚀电位可达到-0.245 V,具有较强的耐腐蚀性。     

脉冲工艺在薄膜制备中的应用

本文综述了国内外脉冲工艺在电弧离子镀和磁控溅射中的应用.脉冲工艺为电弧离子镀净化大颗粒、增强膜基结合力、改善组织形貌、降低沉积温度等起到了重要作用.电弧或溅射离子镀高的离化率为脉冲工艺提供了最好的应用条件.最后,对脉冲工艺在薄膜制备中的应用前景进行了展望.     

使用梯度过渡层的掺Cr碳膜的显微组织特征

为了探究C、Cr两种主要成膜元素在非晶碳膜中的存在和分布状态,采用非平衡磁控溅射离子镀技术制备出了具有梯度过渡层的掺Cr碳膜,利用高分辨透射电子显微术(HRTEM)分析了薄膜的显微组织.结果表明,沉积在硅晶片上的纯Cr底层具有典型的柱状晶结构,其上的梯度过渡层则由各种形态的Cr纳米晶和富碳非晶基质构成.沿薄膜生长方向,随着Cr含量逐渐降低,过渡层中的Cr纳米晶依次形成层片晶、岛状晶和微晶.掺Cr碳膜的工作层则是一种非晶的纳米多层膜.膜中的C始终以非晶态存在,所观察到的结晶相均属金属Cr,同时纯Cr层柱状晶和过渡层中的各种Cr纳米晶都不同程度地具有(110)晶面的择优取向.     

Estimation of Parameters of Universal Distribution of Moments of Failure of Products

A method is proposed for estimating the parameters of a mixture of exponential and Weibull distributions for which the accuracy of preliminary estimates obtained by graphical analysis is refined in accordance with the criterion of maximum likelihood. The efficiency of the proposed method is supported by the results of statistical modeling.     

Evaluation of optical properties of highly scattering media by moments of distributions of times of flight of photons

A novel method for the determination of the optical properties of tissue from time-domain measurements is presented. The data analysis is based on the evaluation of the first moment and the second centralized moment, i.e., the mean time of flight and the variance of the measured distribution of times of flight (DTOF) of photons injected by short (picosecond) laser pulses. Analytical expressions are derived for calculation of absorption and of reduced scattering coefficients from these moments by application of diffusion theory for infinite and semi-infinite homogeneous media. The proposed method was tested on experimental data obtained with phantoms, and results for absorption and reduced scattering coefficients obtained by the proposed method are compared with those obtained by fitting of the same data with analytical solutions of the diffusion equation. Furthermore, the accuracy of the moment analysis was investigated for a range of integration limits of the DTOF. The moment analysis may serve as a comparatively fast method for evaluating optical properties with sufficient accuracy and can be used, e.g., for on-line monitoring of optical properties of biological tissue.     

Estimation of potentialities of methods of summation of direct measurement errors

Conventional methods for summation of direct measurement errors are considered. Conditions under which these methods provide consistent results are stated. It is proposed to utilize for characteristic of the total error, its interval estimator or the half-sum of the value obtained by adding up its arithmetic and geometric random errors.Translated from Izmeritel'naya Tekhnika, No. 4, pp. 10–12, April, 1995.     

空压机轴承箱蜗壳温度探头油封改造

由于空压机进气侧轴承箱蜗壳温度探头密封效果不好,使空压机及其后续管道受到油污染。后将温度探头的O形圈密封改为骨架油封,杜绝了轴承箱漏油问题。文章简介空压机的结构和技术参数,详细介绍了骨架油封的制作和优点。     

Characteristics of mechanical properties of materials in studies of conditions of attainment of marginal states

It is shown that conditions of attainment of marginal states in the material of structural components are formulated on the basis of analysis of force and deformation criteria of formation and development of destruction. The parameters of these criteria are data on types of structural materials, standard and special characteristics of their mechanical properties, structural forms of considered elements of the equipment, and their operating stress loading. In this case, the construction of a system of state equations for describing interrelation of current damage, external actions, and responses to them is based on the concept of calculating variations in properties of materials at all stages of the design life cycle.     

Determination of parameters of microstructural inhomogeneity of deformation of metals by the method of modeling

The article suggests a method of evaluating the microstructural inhomogeneity of deformation of metals by modeling. The method includes the measurement of deformations of metal according to meshes of a dividing grid with small base and the calculation of the distribution parameters of microdeformations in model representation. It is shown that the modeling method makes it possible objectively to evaluate the microinhomogeneity of deformation of metals independently of the chosen mesh size of the dividing grid. New structural characteristics are introduced: the base and wave of variation expressing the degree of crumbling or amalgamation of metal grains by inhomogeneity of deformation.Translated from Problemy Prochnosti, No. 7, pp. 40–44, July, 1991.     

Analysis of the rate of propagation of the wave of change of boiling modes

An approximate analytical expression is derived for the velocity of the front of the wave of change of boiling modes on a rod and on a plate. The impact of the Thomson effect and of the heater orientation in the gravity field is included. Adequate agreement is demonstrated between the derived relations and experimental data.     

水三相点复现的不确定度评定

水三相点是开尔文热力学温度的唯一基准点，也是ITS-90国际温标重要的定义固定点。因此，水三相点不确定度分析对整个温标的建立、温度量值传递起着至关重要的作用。近3年来，中国计量科学研究院研制出一系列高质量的水三相点容器，加强了水三相点的研究，为不确定度的分析提供了更为可靠的实验依据。同时，不确定度的分析也是客观评价新研制容器性能的一个重要指标。因此，根据实验结果对新研制容器所复现的水三相点进行了不确定度评定。评定结果表明，其扩展不确定度为0．16mK(k=2．69，P=0．99)。