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1.
可替代镀铬的离子束技术   总被引:2,自引:0,他引:2  
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2.
计算机技术在我国热处理工业领域的应用和发展   总被引:11,自引:2,他引:9  
从6个方面综合论述了计算机和微电子技术在我国热处理工业领域的应用和发展。(1)计算机模拟技术;(2)CAD技术;(3)过程控制技术和网络系统;(4)热处理计算机预测技术;(5)热处理数据库和专家系统;(6)智能热处理技术与计算机智能化仪表。  相似文献   

3.
离子注入曾因在半导体产业中的巨大成功而名噪于世,但将此技术移植于一般材料(非半导体)的表面改性时却显得步履艰难。尽管早在l0年前,人们已经宣称离子注入使某些材料的耐磨损性提高了3~5倍,也使抗腐性能大为改观。但将实验研究的成果真正推广应用并转化为生产力者尚属少见。诚然,离子注入技术有许多独特的优点.例如,它所形成的材料改性层与基体材料完全溶于一体因而不存在界面;它可在室温下获得用常规技术难以得到的、具有优良性质的非平衡组织,它可保留基体材料的固有性能.而仅使其表层物质性能优化等.  相似文献   

4.
先进热处理技术的发展和展望   总被引:10,自引:4,他引:10  
从环境和可持续发展、能源有效利用、精确生产和优质高效等整体战略出发探讨了现代热处理技术蓬勃发展的形势,归纳了8个方面的“少无”,分别论述了各个“少无”的内含和应用,展望和预测了先进热处理技术的发展前景,提出了热处理生产技术改造的主要途径。  相似文献   

5.
热处理工艺技术是发挥材料强度潜力的重要手段。机械制造业中的60%,汽车、拖拉机中70%的零件,要通过热处理改善性能。我国热处理设备中的,周期炉占95%,氧化气氛炉占90%,热效率低,能耗高,产品质量差。80年代从工业发达国家引进了一些热处理生产线及真空护和可控气氛护组等先进的设备,并大力进行了旧设备的节能改造,使我国热处理的设备水平、工艺技术水平与国外先进水平的差距有了缩小。随着社会主义市场经济的建立,企业主动节能的自觉性正在增强,热处理节能技术也获得了发展,现将热处理节能情况简述如下。1工业炉窑节能技术…  相似文献   

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我国汽车工业感应热处理技术的发展与现状   总被引:2,自引:1,他引:2  
1感应热处理技术的发展感应热处理技术的发展已有50年的历史。30年代,前苏联和美国为了解决曲轴轴颈不耐磨技术难题,开始研究了感应加热和淬火技术。1936年有感应热处理技术专著出版。50年代,国外发达国家的汽车工业,有40%~50%的热处理件采用感应热处理技术。当时R淬表层,心部不强化,主要用于磨损的零件。由于存在开裂和变形问题,碳含量控制在0.4%~0.5%,表面复杂的零件很难得到应用。50年代,我国有了自己的汽车制造工业和感应热处理技术。主要用来提高如曲轴、凸轮轴、花键轴、传动轴、钢板弹簧销、主销、飞轮齿环等零件…  相似文献   

8.
9.
试论先进制造技术中的热处理   总被引:1,自引:0,他引:1  
论述了在先进制造技术迅速发展的情况下,热处理存在的问题及其发展的方向。指出在先进制造技术中的热处理应是基于知识的热处理技术,其作用贯穿于产品与零件的设计,热处理工艺研究和热处理生产过程的各个环节,以计算机模拟为核心的基于知识的热处理将在先进制造技术不断实现跨越中发挥重大作用。  相似文献   

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11.
Silicon carbide (SiC) is a superior material potentially replacing conventional silicon for high-power and high-frequency microelectronic applications. Ion beam synthesis (IBS) is a novel technique to produce large-area, high-quality and ready-to-use SiC crystals. The technique uses high-fluence carbon ion implantation in silicon wafers at elevated temperatures, followed by high-energy heavy ion beam annealing. This work focuses on studying effects from the ion beam annealing on crystallization of SiC from implanted carbon and matrix silicon. In the ion beam annealing experiments, heavy ion beams of iodine and xenon, the neighbors in the periodic table, with different energies to different fluences, I ions at 10, 20, and 30 MeV with 1-5 × 1012 ions/cm2, while Xe ions at 4 MeV with 5 × 1013 and 1 × 1014 ions/cm2, bombarded C-ion in implanted Si at elevated temperatures. X-ray diffraction, Raman scattering, infrared spectroscopy were used to characterize the formation of SiC. Non-Rutherford backscattering and Rutherford backscattering spectrometry were used to analyze changes in the carbon depth profiles. The results from this study were compared with those previously reported in similar studies. The comparison showed that ion beam annealing could indeed induce crystallization of SiC, mainly depending on the single ion energy but not on the deposited areal density of the ion beam energy (the product of the ion energy and the fluence). The results demonstrate from an aspect that the electronic stopping plays the key role in the annealing.  相似文献   

12.
Tissue reconstruction is the aim of regeneration medicine and tissue engineering. One of the techniques is cell sheet engineering, which requires creating a contiguous cell sheet and harvesting it safely. To create a favorable substrate for cultivation, we attempted to fabricate the microstructure at polytetrafluoroethylene (PTFE) surfaces using ion beam irradiation. PTFE is a typical fluoropolymer and it possesses chemical and bioinertness. When the surface is irradiated with an ion beam, it is covered with a large number of microprotrusions, which have an aspect ratio of about 100. We previously reported that fibroblast cells grow and spread between the tops of the protrusions. In this study, we fabricated fine protrusions at both the PTFE and the poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) surfaces. The composition of FEP and PTFE is similar but FEP melts at a lower temperature than PTFE does. These samples were irradiated under controlled temperature and rubbing preparation. Their surface morphology and chemical bonding were observed. When the PTFE surface was irradiated at 350 °C, the protrusions were formed at the lower fluence, with an improved uniformity of shape. This was because the morphological change and evaporation of the thin parts were enhanced during high-temperature irradiation. In the FEP sample, very fine protrusions formed at much lower fluence by irradiation at room temperature. On the surface, the cells spread closely, like a monolayer. Further, the FEP samples were still optically transparent after the irradiation. They have an advantage in that we can observe the living cells attaching to the surface in their natural state without them being killed, fixed, and stained in an optical microscope. We found that the irradiated FEP surface is suitable for making a cell sheet.  相似文献   

13.
Non-conventional methods of machining are used for many engineering applications where the traditional processes fail to be cost-effective. Such processes include Ion Beam Machining (IBM), focused ion beam (FIB) machining and plasma discharge machining. The mechanisms of material removal and associated hardware and software developed for industrial applications of these fascinating electro-physical and chemical machining processes are reviewed together with the latest research findings.  相似文献   

14.
Surface modifications of industrial components, such as the balls, inner and outer rings of bearings, are very difficult to perform for their sophisticated shapes. Plasma immersion ion implantation and deposition (PIIID) offers an effective way for surface treatment of such components. However, implantation doses of these components are not uniform in a conventional PIIID process. To obtain uniform surface modifications, we designed a rotating target holder. Using the target holder and proper process parameters, the PIIID batch treatment of sophisticated-shape components has become easy work. In the PIIID batch treatments of balls, outer and inner surfaces of cylinder-like components, the dose uniformity can be evidently improved by using sample rotation, short width high frequency implantation pulse, and middle-frequency and -voltage glow discharge, respectively. The practical test results reveal that the life of these components can be improved significantly by this novel PIIID batch treatment.  相似文献   

15.
In this work, molybdenum and tungsten ions were implanted onto the DLC films deposited by filtered cathodic vacuum arc. We investigated the effects of ion species and doses on carbon related bonding property such as the ratio of sp3 carbon to sp2 phase, the chemical composition and tribological properties of the DLC films in the range of 200 to 600 °C. The oxidation starting temperature decreased with an increasing ion dose and ion mass owing to higher sp2 carbon fraction. Oxidation of the implanted-metal element, however, keeps the DLC film from carbon sublimation by oxidation, offering stable tribological characteristics by covering it with a metal oxide layer at the high temperature.  相似文献   

16.
Strong adhesion of a silicon carbide (SiC) coating to a WC-Co substrate was achieved through an ion beam mixing technique and the corrosion resistance of the SiC coated WC-Co was investigated by means of a potentiodynamic electrochemical test. In a 1 M NaOH solution, the corrosion current density of SiC-coated WC-Co after heat treatment at 500 °C was about 50 times lower than that for the as-received WC-Co. In addition, the corrosion resistance systematically increases with increasing the SiC coating thickness. On the other hand, for a 0.5 M H2SO4 solution, the corrosion current density for SiC-coated WC-Co was about 3 times lower than that for the as-received WC-Co. We discuss the physical reasons for the changes in the corrosion current density with the different electrolytes.  相似文献   

17.
18.
Uniform alignment of the liquid crystals is necessary for high quality liquid crystal displays (LCDs). In this study, the rubbing-free method was carried out for the modification of the DLC (Diamond Like Carbon) surface by Ar+ ion beam bombardment. By ion beam conditions, such as the energy and fluence of the incident ions at incident angle of 45º, the unidirectional out-of-plane liquid crystal pre-tilt angle is changed. Also, we measured the surface microstructure changes by ion beam using XPS, Raman spectroscopy and AFM analysis. Crystal rotation method was used for measuring the pre-tilt angle of LC and we checked voltage-transmittance (V-T) to evaluate the electro-optical characteristics. Also, the changes of the structural property were analyzed with AFM analysis. LC alignment and electric-optical characteristics which were obtained through LCDs cell alignment by ion beam treatment technology were confirmed that it is identical and suitable to the rubbing method to apply industrial application.  相似文献   

19.
1INTRODUCTION Theelasticmetallic plasticpads(EMP)arewidelyusedinverticalelectricmachinesofhydro powerplants.ThesurfacematerialofEMPis PTFE.ThePTFEhaslowfrictioncoefficientand excellentinsulativity,butthestrength,hardnessandwear resistantpropertiesarenotsatisfacto ry[1].Inordertoimprovethestrength,hardness andwear resistantcharacterofPTFE,somephysi calcomminglingmethodsareused[24].Inrecentyears,therehasbeenever increasing interestinthesurfacemodificationofpolymerstoimprovetheirchemi…  相似文献   

20.
In this study, nano-patterned triangular photonic crystal arrays have been prepared on the surface of blue InGaN/GaN light-emitting diodes by focused ion beam technology. The nitride-based multilayer thin films were grown on c-plane (0001) sapphire substrates by low-pressure metal-organic chemical vapor deposition. The major emission peak wavelength was 468 nm. The nano-patterned array structures were implemented using a dual-beam nanotechnology workstation SMI 3050. The acceleration voltage of Ga ion beam was 30 kV, and the ion beam current was about 100 pA. The air-hole diameter in the triangular array has been 150 nm, while the periodicity ranged from 300 nm to 800 nm. The light-current measurements were carried out to reveal the light output intensity characteristics of the devices. In addition, the current-voltage study was shown with increased operation voltage from 3.0 V to 4.05 V while the period was decreased from 800 nm to 300 nm.  相似文献   

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