|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | 直缝焊管液压成形极限理论预测模型显示文摘直缝焊管广泛应用于汽车车身管状零件液压成形中,焊接区影响着焊管塑性变形规律,准确评价焊管缩颈或破裂现象是工程上倍受关注的问题。基于金相分析法和显微硬度测量法分析高频感应焊管的结构特征,并根据液压成形条件下高频感应焊管的变形特点,提出一种用于计算直缝焊管液压成形极限的理论方法。基于该方法,选用Swift硬化方程和Hill屈服准则推导出直缝焊管液压成形极限理论预测模型,在已知焊管(包含焊接区和基体区)材料性能参数条件下可获得直缝焊管液压成形极限图。运用此理论预测模型,计算出QSTE340高频感应焊管的液压成形极限图。成形极限的计算结果与试验对比表明,二者吻合较好,这证明所建立的直缝焊管液压成形极限的理论预测模型是正确的。 | 陈仙风 于忠奇 侯波 李淑慧 林忠钦 | 2011 | 机械工程学报2011，47，20： | 8 |
| 2 | Impact of Heat Shield Structure in the Growth Process of Czochralski Silicon Derived from Numerical Simulation显示文摘Further development of the photovoltaic industry is restricted by the productivity of mono-crystalline silicon technology due to its requirements of low cost and high efficient photocells.The heat shield is not only the important part of the thermal field in Czochralski(Cz)mono-crystalline silicon furnace,but also one of the most important factors influencing the silicon crystal growth.Large-diameter Cz-Si crystal growth process is taken as the study object.Based on FEM numerical simulation,different heat shield structures are analyzed to investigate the heater power,the melt-crystal interface shape,the argon flow field,and the oxygen concentration at the melt-crystal interface in the process of large Cz-Si crystal growth.The impact of these factors on the growth efficiency and crystal quality are analyzed.The results show that the oxygen concentration on the melt-crystal interface and the power consumption of the heater stay high due to the lack of a heat shield in the crystal growth system.Argon circumfluence is generated on the external side of the right angle heat shield.By the right-angle heat shield,the speed of gas flow is lowered on the melt free surface,and the temperature gradient of the free surface is increased around the melt-crystal interface.It is not conducive for the stable growth of crystal.The shape of the melt-crystal interface and the argon circulation above the melt free surface are improved by the inclined heat shield.Compared with the others,the system pulling rate is increased and the lowest oxygen concentration is achieved at the melt-crystal interface with the composite heat shield.By the adoption of the optimized composite heat shield in experiment,the real melt-crystal interface shapes and its deformation laws obtained by Quick Pull Separation Method at different pulling rates agree with the simulation results.The results show that the method of simulation is feasible.The proposed research provides the theoretical foundation for the thermal field design of the large diameter Cz-Si monocrystalline growth. | ZHANG Jing LIU Ding ZHAO Yue JIAO Shangbin | 2014 | Chinese Journal of Mechanical Engineering2014，27，3： | 4 |
| 3 | 管材轴压胀形仿真精度研究显示文摘针对采用ABAQUS软件对管材轴压胀形进行仿真时,仿真与试验之间存在误差等问题,研究了仿真模型、质量缩放系数、管材约束条件、单元形状和单元尺寸对仿真精度的影响,对比分析了仿真与试验之间胀形轮廓的平均误差以及在轴向任意位置的相对误差。结果表明,在质量缩放系数相同时,采用三维-变形体轴压头模型时的平均误差最低,为6.64%,仿真精度最高;采用轴对称-变形体轴压头模型时,随着质量缩放系数的降低,胀形轮廓的平均误差逐渐降低,仿真精度逐渐提高;当使用轴对称-变形体轴压头模型,管材的约束条件为自由约束,即约束条件与试验环境相似时,仿真精度更高,相比三角形网格,使用四边形网格更为合适,且随着四面体网格尺寸的缩小,仿真精度并没有逐渐提高,应当结合试验,选择合适的单元尺寸。 | 阮钟 杨连发 陈占斌 | 2021 | 塑性工程学报2021，28，9： | 1 |
| 4 | 一种面向双列直插式PCB板的等效建模方法显示文摘针对双列直插式PCB板,提出一种改进的辅助面-集中质量等效建模方法。利用单阶频率等效建立辅助面-集中质量等效模型,研究辅助面尺寸、质量及转动惯量等参数的选取原则,分析元器件的刚度、密度及布局等参数对等效模型计算结果误差的影响规律。通过数值算例表明:运用该等效建模方法进行模态分析,模型节点数量和单元数量大幅减少、对计算机性能要求降低、计算时间大大加快、低阶模态频率相对误差在±1.5%以内。该等效建模方法具有一定的工程应用价值。 | 陈燕 杜平安 滑晓飞 伍文华 | 2012 | 机械设计与制造2012，，12： | 1 |
您所在的机构暂未开通此部分的功能，请联系管理员