抽水蓄能机组过渡过程振动特性研究

对抽水蓄能电站机组开机至额定负荷过程、机组开机对临近机组影响进行了试验研究。分析这两种过渡过程中,蓄能机组和电站厂房的振动特性。结果表明:机组开机至额定负荷过程中,导叶开启及导叶开度回调瞬间对机组冲击较大,机组与厂房出现了较大振动。机组的开机及运行对临近机组的振动没有明显影响,但对临近机组的厂房振动有一定的影响作用,厂房振动出现了明显变大。当机组稳定运行后,对临近机组的厂房振动没有明显的影响。     

轿车用Cr—Ni—Mo齿轮钢带状组织评级探索

Ｃｒ－Ｎｉ－Ｍｏ合金渗碳钢由于钢中合金元素和碳的偏析，经一般退火后存在比较严重的带状组织。合金渗碳钢制和轿车变速箱齿轮时，必须在锻后热处理过程中控制带状组织级别。为了准确地评定带状组织的级别，首先应计算出Ｃｒ－Ｎｉ－Ｍｏ材料的碳当量，然后根据碳当量选用国标ＧＢ／Ｔ１３２９９－９１中的系列标准。根据选定的标准，除条带数量及连续性外并考虑组织中条带的宽窄，对每次试验后的带状组织作比较准确的评定。     

齿轮轴断裂原因分析及预防措施

从断口形貌、显微组织、非金属夹杂物、硬度和化学成分入手,对齿轮轴的断裂原因进行了分析,并提出相应预防措施。结果表明,齿轮轴断裂的主要原因是热点矫直遗留的淬火斑点未进行充分回火和齿轮轴心部出现淬火欠热组织造成。通过改进淬火工艺、矫直及机加工工序后,齿轮轴再无断裂发生。     

氯化镧液 N235 除锌萃取工艺改进与建设

N235除锌线改进升级,优化工艺流程,控制工艺参数,提升萃取能力,利于工序间的配合衔接,便于设备维护操作,提高产品直收率。     

Microstructure and mechanical properties of hypereutectic Al-Si alloy modified with Cu-P

The microstructure and mechanical properties of Al-14.6Si castings modified by Cu-P master alloy under different conditions were studied with optical microscope（OM） and mechanical testing and simulation（MTS）.The results indicate that the Cu-P master alloy possesses not only obvious modification effect,but also longevity effect with more than 8 h on the hypereutectic Al-Si alloy.It is shown from thermal calculation,scanning electron microscope（SEM）,and energy dispersive analysis of X-rays（EDAX） that the modification mechanism of Cu-P on primary silicon in the castings is heterogeneous nucleation around AlP particles.The Cu-P master alloy has no or little modifying effect on eutectic silicon,even though it has obvious modification on primary silicon in the castings.This may be because of the fast transformation of eutectic silicon at a very narrow temperature,which will notably weaken the role of AlP particles as heterogeneous nuclei for eutectic silicon.     

微合金钢中析出相形核过程的三维原子探针研究

应用透射电镜和三维原子探针研究了Nb-V微合金钢在不同处理工艺时的形核过程.控轧控冷(TMCP)钢样品的透射电镜的结果表明出现了(Nb,V)(C,N),大小为几十纳米.三维原子探针的检测结果显示控轧控冷钢样品未出现纳米尺寸的碳氮化物团簇,而淬火钢样品中出现纳米级NbC团簇,经回火的样品中(Nb,V)C和VN团簇最为明显.     

Modification mechanism of cerium on the Al-18Si alloy

The effect of the rare earth cerium （Ce） on the hypereutectic Al-Si alloy under different casting states have been studied by optical microscope and quantitative image analysis. It is found that the size and the quantity of primary silicon in castings decrease with the increase of added Ce in the melt. Meanwhile primary silicon changes from branched shape to fine facetted shape. Although the modification on eutectic silicon in castings also improves with the increase of added Ce in the melt, the effect of modification on eutectic silicon away from primary silicon is more obvious than that on eutectic silicon close to primary silicon. The modification mechanism was analyzed in detail by means of scanning electron microscope equipped with energy dispersive analysis of X-ray and thermodynamics analysis, which included the analysis on the change in standard Gibbs energy of reaction and reaction equilibrium.     

基于CAN总线的伺服电机运动控制系统

介绍了一种基于CAN总线的运动控制系统的硬件和软件设计。本控制系统利用了带有CAN控制器的高速CygnalC8501F040单片机和专用运动控制器LM628来实现对伺服电机的控制。该系统具有结构简单、可靠性高、性能价格比高等特点。     

热作模具钢热疲劳损伤因子的研究

由于Uddeholm标准图谱评定热疲劳程度尚不够完善，无法精确地评定热疲劳裂纹的级别，因此编制了一套计算机图像分析软件，对热疲劳裂纹进行定量分析，并完善了热疲劳损伤因子，用它定量地分析了进口8407和国产4C45MoSiV1热作模具钢的热疲劳性能，揭示了热模钢的热疲劳性能的变化规律，实现了热疲劳裂纹的计算机辅助评定。     

PASSIM7000卷烟机回丝量控制改进

针对PASSIM7000卷烟机供丝系统回丝量控制系统数据采集及处理方式存在的问题,设计出一种新的数据采集及处理方式,采用改变测量位置,及时获取供丝量变化信息;使用激光位移传感器进行精确数值测量;采用最小二乘法对测量数值进行曲线拟合,再根据拟合曲线对回丝量多少进行预测并及时调节等方法,解决了原控制方式造成的反馈滞后,响应不及时等缺陷。改进后的PASSIM7000型卷烟机供丝系统,提高了供丝的均匀性,降低了烟支的空头率。