TiO2涂层激光热冲击损伤机理研究

研究了等离子喷涂TiO2涂层在激光热冲击条件下激光输出功率对涂层损伤的影响,并探讨了涂层的损伤机理.结果表明,随着激光输出功率的增大,TiO2涂层损伤加剧,当激光输出功率为3900W时被击穿;基体上产生热影响区;TiO2涂层在激光热冲击下的微观损伤形貌主要以放射板条状组织和枝状组织为主,并存在大量的裂纹;TiO2涂层消耗激光能量的方式主要是熔化与再结晶并辅以裂纹的萌生与扩展.     

Damage characteristic of interpenetrating phase composites under dynamic loading

In order to investigate the damage characteristic of ceramic-metal interpenetrating phase composite（IPC） under dynamic loading, uniaxial dynamic compression was performed to characterize the failure of SiC/Al composite with 15% porosity using a modifi ed Split Hopkinson Pressure Bar（SHPB）. High speed photography was used to capture the failure procedure and set up the relationship between deformation and real stress. The deformation control technology was used to obtain collected samples in different deformations under dynamic loading. Micro CT technology was utilized to acquire real damage distribution of these specimens. Moreover, SEM was employed in comparing the damage characteristics in IPC. A summary of the available experimental results showed that IPC without lateral confi nement formed double cones. The different features compared with ceramic materials without restraint was shown to be the result of the lateral restraint effect provided by metal phase to ceramics skeleton.     

贝叶斯正规化算法在油藏参数拟合方面的应用

通过已知测井资料对油藏储量进行预测,是目前石油行业一个重要的研究课题。文章介绍了一种基于贝叶斯正规化算法的BP神经网络,并把网络应用到油藏参数拟合过程中的具体方法,该方法对提高石油生产效率、降低成本具有很大的作用。     

Three-Dimensional Simulation of Plasma Jet and Particle Groups in Plasma Spraying

The temperature field, velocity field, as well as species distribution in three-dimensional space are successfully calculated by establishing three-dimensional geometry model and solving plasma jet-substrate interaction equations, optimized particle trajecory models, as well as particle-particle heat transfer equations in three-dimensionalal space. Under typical working conditions, the flying trajectories and distribution of ZrO2 ceramic particles and Ni metal particles are also simulated. Results show that, the plasma jet becomes wider near the substrate, and the stochastic trajectory model is preferable to simulate the turbulent diffusion effect of particles. In addition, Ni metal particles penetrate relatively more deeply than ZrO2 ceramic particles due to larger density.     

医院信息系统中数据库的维护

随着医院信息化的不断普及,Oracle数据库以优良的性能、丰富的管理和开发工具,被各医院首选为信息系统的后台数据库。如果医院信息系统为医院提供生命的血管,那么Oracle关系数据库就是该系统的心脏。为了有一个健全的医院信息系统,必须注重数据库的维护工作。     

ZrO2涂层激光热冲击损伤机理研究

研究了等离子喷涂ZrO2涂层在激光热冲击条件下激光输出功率对涂层损伤的影响,并探讨了涂层的损伤机理.结果表明：随着激光输出功率的增大,ZrO2涂层损伤加剧,并伴随裂纹的萌生与扩展,激光输出功率为1800W时涂层被击穿,激光热冲击对基体的热影响作用较小;ZrO2涂层主要以裂纹的萌生、扩展消耗激光热冲击能量.     

5CrMnMo钢模具型腔超塑性挤压成形的研究

本文是在5CrMnMo 钢超塑性变形特性研究的基础上,对该材料模具型腔超塑性挤压成形的方法进行了研究。结果表明,5CrMnMo 钢模具超塑挤压成形后的型腔棱角完整而清晰,细小条纹十分清楚,这说明用超塑性方法成形该钢模具型腔是可行的。     

ZrO2热障涂层耐高温冲刷性能研究

采用等离子喷涂工艺制备了NiCoCrAlY／ZrO2热障涂层，利用超音速火焰喷涂（HVOF）ZrO2粒子高速冲刷涂层表面，考察ZrO2热障涂层的耐高温冲刷性能。结果表明，等离子喷涂NiCoCrAlY／ZrO2热障涂层具有较好的耐高温冲刷性能，经高温高速粒子冲刷20s后，涂层与基体结合良好，涂层完整，未出现大面积的剥落。等离子喷涂ZrO2热障涂层高温冲刷的主要磨损机理为脉动冲击作用造成的裂纹扩展、涂层颗粒变形磨损和微切削。涂层的耐高温冲刷性能主要取决于涂层的硬度。     

螺旋钻孔机的转速及土壤运动的分析

在工业及民用建筑、港口、桥梁的施工中和一些部门的基建工程中都大力推广采用了灌注桩。我们分析了国内外基础形式和有关技术资料,认为长螺旋钻孔灌注桩基础形式有一定的优越性,它不仅能在常温条件下应用,而且也适用于低温下施工。本文仅就螺旋钻孔机钻杆的转速及土壤在钻杆上的运动过程进行探讨。我们对螺旋钻孔机工作时的工况进行分析,螺旋钻孔机工作装置所产生的切削力大