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1.
脉冲激光沉积技术在磁性薄膜制备中的应用   总被引:8,自引:3,他引:5  
脉冲激光沉积制膜(PLD)是近年来迅速发展起来的制膜新技术,首先简要介绍了脉冲激光沉积技术的原理、特点和优势以及在磁性功能薄膜研究中的应用,最后说明了该技术的最新发展趋势。  相似文献   

2.
脉冲激光薄膜制备技术   总被引:16,自引:2,他引:14  
脉冲激光薄膜沉积是近年来受到普遍关注的制膜新技术。简要介绍了脉冲激光薄膜沉积技术的物理原理、独具的特点和研究发展动态,并介绍了采用脉冲激光薄膜沉积技术制备硅基纳米PtSi薄膜的结果  相似文献   

3.
本文结合国内外研究情况,概括性介绍了用于啁啾脉冲放大系统中的多层介质膜脉冲压缩光栅的激光损伤特性研究进展,包括多层介质膜的损伤、表面浮雕结构的损伤,以及介质膜光栅损伤的影响因素。在关于介质膜光栅激光损伤的影响因素中又分别介绍了槽型结构、制备工艺、激光参数、脉冲数量、热应力和杂质缺陷对其抗激光损伤阈值的影响。最后,从结构设计、制备工艺以及后期处理等方面,介绍了提高多层介质膜光栅抗激光损伤阈值的常用方法。  相似文献   

4.
王联  吴锋  吴川 《材料导报》2008,22(1):13-16
简要介绍了近年来磁控溅射和脉冲激光沉积制膜技术在薄膜型锂离子电池正极材料制备方面的应用研究; 对制膜新工艺及新型正极材料的研究现状进行了概括,认为现阶段新型材料LiFePO4有希望成为薄膜锂电池正极材料的首选,并展望了薄膜型锂离子电池的发展前景.  相似文献   

5.
利用Nd:YAG纳秒激光(波长分别为355、532和1 064 nm)辐照由电子束蒸发技术制备的类金刚石(DLC)薄膜,通过光学显微镜、光学轮廓仪和拉曼光谱仪等分析了辐照后的薄膜样品,结果表明:不同波长的单脉冲激光辐照时,DLC膜的激光损伤阈值不同;同一波长的多脉冲激光辐照时,损伤阈值低于单脉冲辐照阈值;脉冲激光辐照对DLC膜具有改性作用,受辐照薄膜区域表层发生了石墨化、剥落和气化效应,致使DLC膜表面出现了隆起和弹坑,隆起高度和弹坑深度与激光能量密度大小和脉冲个数有关.  相似文献   

6.
采用1kHz飞秒激光(脉宽148fs,中心波长775nm)对石英衬底的金膜的烧蚀过程进行了研究.单脉冲与多脉冲的烧蚀阈值可以通过烧蚀点的直径平方与所用的激光能流的关系曲线获得.通过累积能流和烧蚀脉冲数的关系,可以得到金膜的脉冲累积因子.采用飞秒激光加工材料的一些特点可以合理解释单脉冲阈值附近获得的一些实验现象.  相似文献   

7.
新型界面结合强度检测技术理论及实验研究   总被引:1,自引:0,他引:1  
膜/基界面结合强度的测量与评价已成为硬质薄膜技术发展与应用的关键问题.提出了1种新的测量方法———激光冲击检测技术,分析了在脉冲激光作用下,薄膜脱落的机理与数学模型.以测定TiN薄膜界面结合强度为例,用650~1000 mJ的脉冲激光对膜层进行加载,并采用体式显微镜和扫描电镜对薄膜的脱落情况进行表面观察,根据反射信号检...  相似文献   

8.
脉冲激光沉积有机薄膜   总被引:1,自引:0,他引:1  
脉冲激光沉积(PLD)技术是一门新兴的薄膜制备技术,在无机薄膜的制备和研究方面取得了令人满意的成果,技术也比较成熟.但利用脉冲激光沉积技术制备和研究有机膜方面的工作开展较晚,工作也比较少,尚未形成一个比较系统的体系.因此开展有机薄膜的脉冲激光沉积研究将具有重要的意义.  相似文献   

9.
石英晶振的谐振频率在出厂前都需要进行微调,使之达到需要的标称值。本文提出激光调频的新技术,利用适当激光能量使电极膜层汽化减薄,从而使晶振的频率精确升高到预期值,重点研究了激光器的工作电流和Q脉冲宽度等参数对晶振频率微调的影响。实验结果表明:当工作电流太小(10A)或Q脉冲宽度太大(10μs)时,激光脉冲的峰值能量密度太小不足以有效实现频率微调;当工作电流和Q脉冲宽度比较合适(电流约为11A,Q脉冲宽度为4~10μs)时,石英晶振的谐振频率可以被线性地调节,此时对晶振其它电性能参数影响很小;当工作电流过大(11A)或Q脉冲宽度过小(4μs)时,激光脉冲能量密度过大,很容易对电极膜造成损伤而导致不能起振。  相似文献   

10.
张成武  李国卿  柳翠  关秉羽 《真空》2004,41(4):114-116
介绍了脉冲磁过滤阴极电弧法制备四面体非晶碳膜(tetrahedral amorphous carbon即ta-C),并对制得的薄膜表面形貌、硬度、电阻等进行了测试.结果表明,脉冲磁过滤阴极电弧法制备的ta-C膜有优良的性能.拉曼光谱分析显示,制得的薄膜为非晶结构,有明显的sp3结构特征,符合ta-C膜的特征峰.  相似文献   

11.
Permeable crystalline materialcan permeate into pores and cracks of concrete and catalyze the reaction between Ca(OH) 2and unhydrated cement to generate a great quantity needle non-soluble crystals, which can stop up the pores and cracks of concrete, and increase the impermeability of concrete. This paper reported the results of a study conducted to evaluate steel reinforcement corrosion of concrete specimens uncoated and coated with permeable crystalline material as well as mixed with the permeable crystalline material. The properties evaluated for corrosion test were water impermeability, water absorption, compressive strength and potential. The results of water impermeability, water absorption, compressive strength clearly showed that the permeable crystalline material could prohibit water, any soluble salts and moisture from penetrating the concrete to cause corrosion, leaking, and other problems, and it did increase the compressive strength, which was favorable for protection of corrosion of reinforcing steel. Moreover, it was concluded from the potential-time curve that the steel reinforcement of uncoated specimen was in the state of activation whereas that of other specimens coated and mixed with the permeable crystalline material was in the state of inactivation. Above all, it was indicated that the permeable crystalline materialis very effective to protect the steel reinforcement of concrete from corrosion.  相似文献   

12.
In this paper, the principle of spurting take off lacquer were introduced; and with orthogonal method the unsaturate polyester was prepared ;it was easy to peel airplane paint layer off with this material and equipment.  相似文献   

13.
Quality Study of Honeycomb Core Shaping Without Wax Stabilization   总被引:1,自引:0,他引:1  
Sandwich panels utilizing honeycomb cores result in lightweight, high-strength units that are very rigid. Indeed, they give honeycomb panels the best strength-to-weight ratio of any construction type available. Conventionally, the wax is poured into the cell of the core to strengthen the structure and prevent the core from being crushed during milling. Much time and labor is required to wax, mill, and clean the cores. In this study, the process of pouring wax into the core was skipped. In other words, the cutter directly milled the core. Experiments showed that the compressive strength of the core produced without wax stabilization was only 3% lower than that of cores produced using the traditional method. In addition, the drum peel strengths of cores produced without wax stabilization were 38.4% higher than cores produced using the traditional method, in which residual wax seriously polluted the adhesive. It was also found that eliminating the wax process can reduce costs.  相似文献   

14.
In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.  相似文献   

15.
Polylactic acid (PLA) is one of the most widely used open source fused filament fabrication materials due to its ease of extrusion, biodegradability, and mechanical strength. The mechanical strength of PLA largely depends on the proper growth of its semi-crystalline structure, which can be severely impaired by a low rate of crystallization, particularly in open source printers. This can be further aggravated by the non-uniform thermal distribution of heat that causes improper curing among the extruded beads of the printing material. As a result, PLA printed on open source printers does not achieve the best mechanical properties. This research, for the first time, proposes an additive-free solution implemented through a detailed set of experimentation to improve the curing rate through in-process temperature variations to cure the joints among the beads. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy is used to confirm the improvements in the bead joints. This work is conducted in two phases of experiments. In the first phase, a full factorial ANOVA is used to investigate various process parameters and the important variables are used in the second phase to print test specimens in four different sets.  相似文献   

16.
In continuous hot-dip galvanization process the corrosion and chemical stability of the sink roll in the galvanizing bath are important problem which effects on the quality and productivity. In order to protect the sink roll the carbide cermet and/or ceramic coatings were deposited on the surface of the sink roll. The WC-, Cr3 C2-cermet coatings were deposited by high velocity oxygen fuel (HVOF) spray, respectively. The coating samples were immersed in molten Zn-alloy containing 50 wt % aluminum at 833 K for 24 hr and 144 hr, respectively. The inter-diffusion and inter-reaction of Zn, Al and elements in coating and corrosion behaviors of these coatings were investigated by XRD, SEM and EPMA etc. The corrosion mechanisms of the carbide cermet coatings and ceramic coatings in molten High Al-Zn-alloy were approached.  相似文献   

17.
In many situations, ice often adheres to a cooling solid surface, frequently causing serious accidents. It is critical to clarify the mechanism of ice adhesion to the cooling surface in order to prevent ice adhesion. In a past study, the shearing stresses of two kinds of test plates with a copper surface having the higher thermal conductivity were measured. The shearing stress corresponds to ice adhesion force. Both shearing stresses were significantly different; however, the cause remains unclear.Therefore, the present study focuses on an oxide layer as the main factor causing the difference of both shearing stresses; the influence of the oxide layer formed on shearing stress was discussed. And in the removal and reformation processes of the oxide layer, the time variation of the shearing stress was clarified. Moreover, the relationship between the state of the copper surface and the shearing stress was also clarified by surface analysis.  相似文献   

18.
During his inspection in Henan Province in May, Chinese President Xi Jinping stressed to "push forward the transformation from China Speed to China Quality, from Made in China to Created in China, and from Chinese Products to Chinese Brand". The "Three Transformations" are the specific requirements and goal of China's national development in the context that market should play a decisive role in the allocation of resources.  相似文献   

19.
正When you are enjoying the green,energy-saving and healthy lighting of IKEA LED luminaire,you may not realize that most of IKEA’s LED bulbs are produced by the LED luminaire smart manufacturing system of Hangzhou Zhongwei Photoelectricity CO.,LTD(ZVISION).No longer enclosed in the laboratory,the product standards are brought into the factory workshop and even to the entire production process.Thus,the standards are promoted and applied in a favorable way by enterprises,benefitting consumers with high quality products.  相似文献   

20.
正The international standard,ISO 8124-6,Safety of toys–Part 6:Certain phthalate esters in toys and children’s products,was officially issued by ISO worldwide on August 15.It was the first time for Chinese experts to lead the ISO standard development in toys industry.The standard was drafted by a group of Chinese experts from SAC/TC for toys and relevant Chinese departments and finally completed by a dedicated international group of experts.ISO 8124-6 makes a substantive breakthrough in the aspects of the scope of toys,limitation of plasticizer types,control of test cost,accuracy of test,operation convenience,etc.,offering the operational guidance for toy manufactures and testing laboratories.  相似文献   

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