共查询到20条相似文献，搜索用时 875 毫秒
1.
文英 《中学生数理化(高中版)》2003,(1)
Ｓｅｃｔｉｏｎ1 :ＢｒｅａｋｄｏｗｎｏｆＦｏｒｃｅｓＹｏｕｃａｎｂｒｅａｋｄｏｗｎｆｏｒｃｅｓｉｎｔｏｓｅｖｅｒａｌｃｏｍｐｏｎｅｎｔｓｅａｓｌｉｌｙ.Ｆｏｒｅｘａｍｐｌｅ,ｔｈｅｆｏｒｃｅＦ1 ａｔ30ｄｅｇｒｅｅｃａｎｂｅｂｒｏ ｋｅｎｉｎｔｏｔｗｏｆｏｒｃｅｓ:ＦｘａｎｄＦｙ,ａｎｄＦｘ=ｃｏｓ30°×Ｆ1 ,Ｆｙ=ｓｉｎ30°×Ｆ1 .Ｓｅｃｔｉｏｎ2 .ＴｗｏＤｉｍｅｎｓｉｏｎａｌＦｏｒｃｅｓｉｎｔｏＯｎｅＹｏｕｃａｎｃｏｍｂｉｎｅｔｗｏｆｏｒｃｅｓｉｎｔｏｏｎｅ.ＳｕｐｐｏｓｅＴｏｍｐｕｓｈｅｄａｂｏｘｗｉｔ… 相似文献
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1 Ｉｎｔｒｏｄｕｃｔｉｏｎ Ｓｉｎｃｅｔｈｅ 90’ｓ ,ｔｈｅｆｅｍｔｏｓｅｃｏｎｄｌａｓｅｒｔｅｃｈｎｉｑｕｅｓｈａｖｅｂｅｅｎｕｓｅｄｔｏｓｔｕｄｙｖａｒｉｏｕｓｕｌｔｒａ ｐｒｏｃｅｓｓｗｉｔｈｉｎｍａｔｅｒｉａｌｓ,ｂｅｃａｕｓｅｏｆｉｔｓｈｉｇｈｔｉｍｅ ｒｅｓｏｌｕｔｉｏｎ .Ｉｎｃｈｅｍｉｃａｌｒｅａｃｔｉｏｎｓ ,ｃｈｅｍｉｃａｌｂｏｎｄｂｒｅａｋｉｎｇｏｒｂｏｎｄｆｏｒｍａｔｉｏｎｉｓｏｎｔｈｅｓｃａｌｅｏｆｆｅｍｔｏｓｅｃｏｎｄ (10 - 15ｓｅｃ ｏｎｄ) [1] .Ｗｉｔｈｆｅｍｔｏｓｅｃｏｎ… 相似文献
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ＮＴＲＯＤＵＣＴＩＯＮＴｅｍｐｅｒａｔｕｒｅｆｉｅｌｄｃｈａｎｇｅｗｉｌｌｐｒｏｄｕｃｅｔｈｅｒ ｍａｌｓｔｒｅｓｓｅｓｉｎｓｔｒｕｃｔｕｒｅｓ.Ｉｔｉｓｗｅｌｌｋｎｏｗｎｔｈａｔｄｉｆｆｅｒｅｎｔｍａｔｅｒｉａｌｓｇｅｎｅｒａｔｅｄｉｆｆｅｒｅｎｔｓｔｒｅｓｓｒｅ ｓｐｏｎｓｅｓ ,ａｎｄｔｈａｔｉｎｓｏｍｅｃａｓｅｓ,ｔｈｅｒｍａｌｓｔｒｅｓｓ ｅｓａｒｅｌａｒｇｅｅｎｏｕｇｈｔｏｃａｕｓｅｓｔｒｕｃｔｕｒｅｆａｉｌｕｒｅ .Ｓｏｉｔｉｓｍｅａｎｉｎｇｆｕｌａｎｄｉｍｐｏｒｔａｎｔｔｏｓｔｕｄｙｄｙ… 相似文献
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张素英 《邢台职业技术学院学报》2001,18(3):25-26
Ａｓａｃｏｌｌｅｇｅｓｔｕｄｅｎｔ,ｙｏｕｈａｖｅｔｏｒｅａｄａｂｒｏａｄｖａｒｉｅｔｙｏｆｍａｔｅｒｉａｌ.ＹｏｕｒｓｕｃｃｅｓｓｏｆｃｏｌｌｅｇｅＥｎ ｇｌｉｓｈｒｅａｄｉｎｇｄｅｐｅｎｄｓ ,ｉｎｐａｒｔ ,ｏｎｈｏｗｗｅｌｌｙｏｕｃａｎｒｅａｄａｎｄｅｖｅｎｗｒｉｔｅａｎｄｈｏｗｗｅｌｌｙｏｕｃａｎｃｏｎ ｎｅｃｔｔｈｅｓｅｔｗｏｐｒｏｃｅｓｓｅｓ .Ｒｅａｄｉｎｇｗｉｔｈｕｎｄｅｒｓｔａｎｄｉｎｇｄｅｐｅｎｄｓｏｎｔｈｅｉｎｔｅｒｐｌａｙｏｆｆｏｕｒｆａｃｔｏｒｓ:ｖｏｃａｂｕｌａｒｙ ,ｓｔｒｕ… 相似文献
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ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｍｉｃｒｏｓｔｒｕｃｔｕｒｅｏｆｔｈｉｎｆｉｌｍｓｐｌａｙｓａｃｒｕ ｃｉａｌｒｏｌｅｉｎａｗｉｄｅｖａｒｉｅｔｙｏｆｐｈｙｓｉｃａｌｐｒｏｃｅｓｓｅｓ.Ｔｈｅｒｅａｒｅｃｌｅａｒｅｖｉｄｅｎｃｅｓｔｈａｔｍａｎｙｐｈｙｓｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆａｔｈｉｎｆｉｌｍｖａｒｙｄｒａｍａｔｉｃａｌｌｙａｓｉｔｓｍｉｃｒｏｓｔｒｕｃｔｕｒｅｃｈａｎｇｅｓ (Ｈａｕｓｅｔａｌ.,1 987) .Ｆｏｒｉｎｓｔａｎｃｅ,ｒｏｕｇｈｓｕｂｓｔｒａｔｅｓｃａｎｂｅｕｓｅｄｔｏｆａｂｒｉｃ… 相似文献
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1 Ｉｎｔｒｏｄｕｃｔｉｏｎ ＬｅｔＸ ,ＹｂｅｔｗｏＨｉｌｂｅｒｔｓｐａｃｅｓａｎｄｌｅｔＡ∈Ｂ(Ｘ ,Ｙ) ,ｉ .ｅ .,ａｂｏｕｎｄｅｄｌｉｎｅａｒｏｐｅｒａｔｏｒ .ＣｏｎｓｉｄｅｒｔｈｅｏｐｅｒａｔｏｒｅｑｕａｔｉｏｎＡｘ =ｙ (1.1)ＩｆＲ(Ａ) ,ｉ .ｅ .,ｔｈｅｒａｎｇｅｏｆＡ ,ｉｓｎｏｎ ｃｌｏｓｅｄｉｎＹ ,Ｅｑ .(1.1)ｉｓｉｌｌ ｐｏｓｅｄ[1] .Ｍａｎｙｉｍｐｏｒｔａｎｔｐｒｏｂｌｅｍｓｉｎａｐｐｌｉｅｄｓｃｉｅｎｃｅｓ ,ｅｓｐｅｃｉａｌｌｙｉｎｖｅｒｓｅｐｒｏｂｌｅｍｓ ,ｒｅｓｕｌｔｉｎｔｈｉｓｋｉ… 相似文献
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ＩｎｔｒｏｄｕｃｔｉｏｎＡｓａｃｏｌｌｅｇｅｔｅａｃｈｅｒｏｆＥｎｇｌｉｓｈ ,Ｉｈａｖｅｅｘｐｅｒｉｅｎｃｅｄｖａｒｉｏｕｓｐｒｏｂｌｅｍｓｉｎｍｙｒｅａｄｉｎｇｃｏｕｒｓｅ .ＳｉｎｃｅＥｎｇｌｉｓｈｉｓｏｕｒｓｅｃｏｎｄｌａｎｇｕａｇｅ ,ｍｏｓｔｏｆｔｈｅｔｉｍｅｍｙｓｔｕｄｅｎｔｓｆａｃｅｔｈｅｌａｎ ｇｕａｇｅｂａｒｒｉｅｒｉｎｓｕｃｈａｒｅａｓａｓｌｉｓｔｅｎｉｎｇ ,ｓｐｅａｋ ｉｎｇ ,ｒｅａｄｉｎｇａｎｄｗｒｉｔｉｎｇ .Ａｍｏｎｇａｌｌｔｈｅｐｒｏｂ ｌｅｍｓ,ｔｈｅｍｏｓｔｃｏｍｍｏｎｏ… 相似文献
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赵荣乐 《上海大学学报(英文版)》2000,4(2):171-174
1 Ｉｎｔｒｏｄｕｃｔｉｏｎ Ｓｑｕａｓｈｍｏｓａｉｃｖｉｒｕｓ (ＳｑＭＶ)ｉｓｏｎｅｏｆｔｈｅｍｏｓｔｉｍ ｐｏｒｔａｎｔｃｕｃｕｒｂｉｔｖｉｒｕｓｅｓ[1～ 3] ,ａｎｄｉｔｃａｕｓｅｓｇｒｅａｔｌｏｓｓｅｓｉｎｍｕｓｋｍｅｌｏｎｐｒｏｄｕｃｔｉｏｎ[4 ] .Ｏｎｅｏｆｔｈｅｍａｉｎｗａｙｓｔｏｃｏｎｔｒｏｌｐｌａｎｔｖｉｒｕｓｄｉｓｅａｓｅｓｉｓｔｈｅｉｎｄｕｃｅｍｅｎｔｏｆｒｅｓｉｓ ｔａｎｃｅｔｏｖｉｒｕｓｅｓ[5] ｂｙｓｏｍｅｂｉｏｌｏｇｉｃａｌａｎｄｎｏｎ ｂｉｏｌｏｇｉｃａｌｆａｃｔｏｒｓ[6～ 9… 相似文献
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ＩＮＴＲＯＤＵＣＴＩＯＮＩｎｅｘｃａｖａｔｉｏｎ ,ｎｏｒｍａｌａｎａｌｙｓｉｓｉｓｎｏｔｇｏｏｄｅｎｏｕｇｈｔｏｍｅｅｔｅｎｇｉｎｅｅｒｉｎｇｎｅｅｄｓｄｕｅｔｏｔｈｅｕｎ ｃｅｒｔａｉｎｔｙｏｆｆｏｒｃｅｓａｐｐｌｉｅｄｏｎｂｒａｃｅｓｔｒｕｃｔｕｒｅｓ,ｓｏｉｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓ,ａｎｄｓｏｉｌｍｏｄｅｌｕｓｅｄ .Ｔｏｇｕａｒａｎｔｅｅｔｈａｔｔｈｅｃｏｎｓｔｒｕｃｔｉｏｎｐｒｏｃｅｓｓｃａｎｂｅｓｍｏｏｔｈｌｙｐｅｒｆｏｒｍｅｄ ,ｍｅａｓｕｒｅｍｅｎｔｓｉｎｓｉｔｕａｒｅｕｓｕａ… 相似文献
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A semi-analytical method was proposed to solve the mechanics problem of stamping a sheet on elastic die.The sheet was divided into four parts according to its deformation and contact with the punch and elastic die.Analytical solutions were derived individually for each part by using elastic large deflection and plastic large deformation.Solutions were found out with MATLAB by developing a numerical algorithm.Interface forces were obtained by iteration under the compatibility conditions between the neighboring parts of the sheet.Computation shows the method is efficient. 相似文献
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This work aims to study the springback behaviour of electrogalvanised (EG) steel sheets during the air bending process. Experiments
have been conducted to analyse the influence of various parameters such as coating thickness, orientation of the sheet, punch
radius, die radius, die opening, punch velocity, and punch travel on springback behaviour. It is established that the springback
increases with increasing coating thickness, punch radius, punch travel, die radius, die opening, and punch velocity. The
90° orientation exhibits higher springback than 0° orientation. 相似文献
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冷轧薄板冲压性能的影响因素 总被引：2，自引：0，他引：2
闫志波 《石家庄职业技术学院学报》2006,18(2):14-16
概述了冷轧薄板的冲压性能的评价指标,详细介绍了冷轧薄板的化学成分、织构和晶粒尺寸、表面质量、厚度尺寸公差、冷轧工艺条件、拉伸试验值对冷轧薄板冲压性能的影响,并应用ANS YS/LS-DYNA软件对板材弯曲成形过程进行了模拟. 相似文献
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冲裁模上凸、凹模之间的间隙是影响制件质量的主要因素,然而要保持冲压生产时凸、凹模间隙的均匀,模具的设计、选材、加工和装配各个环节都至关重要。笔者在深入分析了冲压工件时出现单边毛刺的可能情况及原因,研究了凸、凹模间隙均匀的控制方法,并提出了模具使用后间隙变化的调整、修配措施,对冲压生产具有实际指导意义。 相似文献
15.
ZHANG Dong-juan CUI Zhen-shan CHEN Zhi-ying RUAN Xue-yu 《浙江大学学报(A卷英文版)》2007,8(2):237-244
INTRODUCTION As an important manufacturing method, bending has been widely used in modern industries to produce stamping parts such as frames, channels, braces, brackets and other structural parts. The understanding and development of bending mechanics are aimed at achieving two kinds of information which are very important for industrial production. One is to predict springback for dies design and compensation in order to obtain high dimension accuracy of bending parts. The other is to … 相似文献
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在分析国内外任意三维曲面激光打标现状的基础上,通过介绍基于三维激光振镜系统自动变焦原理和面向三维激光打标加工的三维纹理数学模型的生成过程,研究了产品三维stl面展开的纹理映射算法,实现了产品三维曲面无尺寸变形和形状扭曲的激光打标方法。 相似文献
17.
匡和碧 《深圳职业技术学院学报》2021,(1)
文章简要概述了国内冲压模具设计行业的现状,阐述了模具凸、凹模刃口尺寸确定的新方法,并以FOX面板冲孔模设计为例,介绍了基于PressCAD冲孔模设计的方法、步骤。同时对PressCAD的模具资料设定、模板绘制、模具组立图、模板分离等命令的功能和参数设置方法作了深入探讨. 相似文献
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以取向硅钢的径向(与轧向分别成0°、25°、45°、55°、70°和90°)拉伸变形行为为案例,探讨影响汽车板深冲性能的因素。结果表明,材料的滑移系和强度是影响其延伸率和深冲性能的两个重要因素。由于具有强烈的γ-纤维织构的汽车板法向强度高、径向强度低,并且各向异性小,延展性好,因此其深冲性能极好。利用X-射线织构分析技术可以较好地评估其深冲性能。 相似文献
20.
The recently developed elastic-viscoplastic self-consistent model with various self-consistent schemes was applied to study the effect of basal texture on the mechanical behavior of magnesium alloy AZ31B sheet. The influence of the basal texture was investigated using various initial textures generated by artificially tilting the measured texture of the reference AZ31B sheet around in a transverse direction. The material parameters for the various models were fitted to experimental uniaxial tension and compression along the rolling direction and were then used to study the effects of the basal texture on the yield stress, R value, ultimate stress and uniform strain under uniaxial tension. The effect of the basal texture on sheet metal forming was further assessed by calculating the limit strain under in-plane plane strain tension. An assessment of the predictive capability of polycrystal plasticity models was made based on comparisons of predictions and experimental observations. Among the available self-consistent approaches, the Affine self-consistent scheme resulted in the best overall performance. 相似文献