数控切割机图形微机的研制

本文介绍了图形微机在数控切割机中的作用,工作方式以及其设计方案。详细描述了各模块的功能和实现方法。     

矩形和T形截面受弯构件承载力计算

本文根据砼结构设计规范（ＧＢＪ１０－８９）给出了常见矩形，Ｔ形、工字形截面受弯构在Ａｓ‘处于弹性状态或屈服时，所需受拉钢筋Ａｓ的直接求解设计方程，这些方程可用于手算也可用于电算。     

35MnVS易切削非调质钢在汽车零件上的应用

由一汽集团和大连钢厂研制的３５ＭｎＶＳ钢，作汽车发动机连杆比５５钢的性能稳定。应用结果表明３５ＭｎＶＳ钢ＣＡ６１０２发动机连杆具有优良的锻造性能和切削加工性能，并显示出明显的经济效益。     

通过区域块投影方法直接绘制三维数据场

直接的体绘制技术提供了在一幅图形内显示三维数据场各种信息的巨大潜力。然而，生成这样的图形是极其昂贵的，而且高质量图形的绘制远远达不到交互实现的水平。体元投方法之所以能引起人们的极大举是因为在处理过程中充分地利用了体元的空间连贯性。本文提出了一个更有效的体绘制方法：区域块投影方法（Ｂｌｏｃｋ Ｐｒｏｊｅｃｔｉｏｎ Ｍｅｔｈｏｄ）。这一算法不仅利用了体元的空间连贯性而且还充分地利用了数据场函数值分布的     

Chromostereopsis: a multicomponent depth effect?

Colours on a flat two-dimensional surface can appear to lie in different depth planes. This phenomenon, readily seen on a computer monitor, is called chromostereopsis. Typically, red objects appear closer to the observer than blue objects. Although research on chromostereopsis has a history of over one hundred years, there are still aspects of it that are not fully explained. The simplest (and earliest) explanation proposes that a combination of chromatic aberration and the displacement of the fovea from the eye's optical axis is responsible for the illusion. Recent research supports the notion that other factors need to be taken into account, for example the eccentric location of the pupils and the Stiles-Crawford effect. We describe some of our own research that suggests that in many displays at least part of any perceived depth is due to luminance differences, bright objects appearing closer than dim ones.     

环境湿度对聚酰亚胺驻极体性能的影响

本文讨论了恒流电晕过程中环境湿度对聚酰亚胺驻极体表面电位建立的影响,分析了恒压充电后环境湿度对聚酰亚胺驻极体电荷储存稳定性的影响。利用热脉冲技术研究了不同湿度下电晕充电的聚酰亚胺薄膜沉积电荷平均深度向背电极的迁移规律。     

Fe-Cu-C-MnS烧结易切削钢中MnS的透射电镜分析

通过透射电子显微镜（ＤＥＭ）分析了Ｆｅ－Ｃｕ－Ｃ－ＭｎＳ烧结易切削钢及含微量硫、磷和钙的Ｆｅ－Ｃｕ－Ｃ－ＭｎＳ烧结钢中的ＭｎＳ，并采用电子衍射分析其晶体结构，发现：在烧结过程中，不同烧结钢中ＭｎＳ结构是否发生变化取决于ＭｎＳ的添加方式和其他元素的存在。     

易切削奥氏体不锈钢303F和316F的机加工性能

仪器仪表用３０３Ｆ，３１６Ｆ，Ｃａ－Ｓ易切削奥氏体不锈钢的切削，钻削加工性能分别优于０Ｃｒ１８Ｎｉ９和０Ｃｒ１８Ｎｉ１２Ｍｏ２不锈钢。     

Mechanical and experimental investigation on nuclear fuel fretting

A mechanical approach to the nuclear fuel fretting problem is studied in this paper to find a possible and efficient way of a wear restraint. Two different contours of the spacer grid spring and dimple were developed to increase the contact area. Fretting wear experiments were carried out for the developed springs and tube specimens. Contact forces of 10 and 30 N, and slip displacements of 50–100 μm were applied under the environment of air as well as water at room temperature. Wear scars on the rods were examined to observe the effect of the mechanical approach on the wear. Especially, the influence of a contour deviation which occurred during fabrication and the wear particle accumulation in the clearance region were investigated in detail. It was found that the contact shape influenced the feature and the behavior of the length, width and volumetric shape of the wear. For the model of fuel fretting wear, equivalent depth (D_e) is suggested as a new parameter that can represent the wear severity.     

Automatic feedrate adjustment for pocket machining

As high-speed machining and unmanned machining become common, the demand for cutting-load regularization increases, so NC machining can be more efficient. To be presented is a simple cutting-load regularization method for pocket machining. As the conventional off-line approaches where cutting-load is predicted and cutting parameters are adjusted before actual cutting, the proposed method requires a cutting force model, which is quite simplified with the function of two independent variables. One is the geometric measure so called 2D chip-load (cutter-engagement angle or effective cutting depth), and the other is the feedrate. Based on the 2D chip-load analysis for the concave line-line segment of the NC tool path, the adjusted feedrate is calculated by using the simplified-cutting force model (SCFM) obtained by the cutting experiment with a tool dynamometer. The concept of the automatic feedrate adjustment (AFA) method to be proposed is very simple, and the implementation requires little effort. Furthermore, the proposed method does not need much calculation time because there are no complex calculations or cutting simulation.