基于UG／POST五轴后置处理技术研究（下）

计算角度变换的数学模型为（1）c角的计算分四种情况根据前述工作台的旋转过程,并且考虑机床结构、工件装夹情况,坐标变换过程可归纳如下：①首先使工件坐标系的原点与机床坐标系的原点一致。②工件绕Zw轴顺时针旋转C角,坐标变换矩阵为T1。③工件绕Aw轴顺时针旋转A角,坐标变换矩阵为T2。     

渐开线齿轮的测量计算

渐开线齿轮在精密机械传动中具有广泛的应用,但其本身的机械精度一般比较高,测量难度较大,故在实际测量中,一般采用圆棒测量的方法测量肘值来确定。     

浅谈我国数控机床的现状与发展趋势

随着社会生产和科学技术的不断进步,各类工业新产品层出不穷。机械制造产业作为国民工业的基础,其产品更是日趋精密复杂,特别是在宇航、航海、军事等领域所需的机械零件,精度要求更高,形状更为复杂且往往批量较小,     

建筑施工技术中的常见问题及对策探讨

近年来，随着科学技术的进步，我国的建筑施工技术也逐渐成熟并被广泛的应用在施工操作中，而在工程施工的过程中，施工技术及其管理工作在很大程度上影响到工程的进度以及项目的质量水平，因此说一定要格外注意这一点。但是从目前来看，在建筑工程施工的过程中，技术的应用还存在着一定的问题，本文就对常见的问题进行分析，并指出相应的解决对策。     

基于SiO2溶胶的稳定性的Cu/SiO2催化体系在化学机械抛光中的应用研究

There is a lot ofhydroxyl on the surface ofnano SiO2 sol used as an abrasive in the chemical mechanical planarization （CMP） process, and the chemical reaction activity of the hydroxyl is very strong due to the nano effect. In addition to providing a mechanical polishing effect, SiO2 sol is also directly involved in the chemical reaction. The stability of SiO2 sol was characterized through particle size distribution, zeta potential, viscosity, surface charge and other parameters in order to ensure that the chemical reaction rate in the CMP process, and the surface state of the copper film after CMP was not affected by the SiO2 sol. Polarization curves and corrosion potential of different concentrations of SiO2 sol showed that trace SiO2 sol can effectively weaken the passivation film thickness. In other words, SiO2 sol accelerated the decomposition rate of passive film. It was confirmed that the SiO2 sol as reactant had been involved in the CMP process of copper film as reactant by the effect of trace SiO2 sol on the removal rate of copper film in the CMP process under different conditions. In the CMP process, a small amount of SiO2 sol can drastically alter the chemical reaction rate of the copper film, therefore, the possibility that Cu/SiO2 as a catalytic system catalytically accelerated the chemical reaction in the CMP process was proposed. According to the van＇t Hoff isotherm formula and the characteristics of a catalyst which only changes the chemical reaction rate without changing the total reaction standard Gibbs free energy, factors affecting the Cu/SiO2 catalytic reaction were derived from the decomposition rate of Cu （OH）2 and the pH value of the system, and then it was concluded that the CuSiO3 as intermediates of Cu/SiO2 catalytic reaction accelerated the chemical reaction rate in the CMP process. It was confirmed that the Cu/SiO2 catalytic system generated the intermediate of the catalytic reaction （CuSiO3） in the CMP process through the removal rate of copper film, infrared spectrum and AFM diagrams in different pH conditions. FinalLy it is concluded that the SiO2 sol used in the experiment possesses stable performance; in the CMP process it is directly involved in the chemical reaction by creating the intermediate of the catalytic reaction （CuSiO3） whose yield is proportional to the pH value, which accelerates the removal of copper film.     

次高压背压式汽轮机机组改造

<正>1机组情况石家庄双联化工有限责任公司有1台B12-4.9/0.98型次高压背压式汽轮机机组,进汽压力4.9 MPa,温度435℃,最大进汽量150 t/h,1个双列调节级,3个压力级,套装转子,喷嘴调节。2003年,针对热用户用蒸汽量少、达不到设计要求,对汽轮机机组通流部分作过一次调整,目的作为抽背压机组使用。在实际运行中,锅炉主汽压力在4.1~4.2 MPa,低于原机组设计进汽压力(4.9 MPa),背压在高限约1.1 MPa纯背压方式运     

以工作流为核心的PDM系统在轴承行业中的实施

介绍了PDM系统以及工作流管理的技术特点,并提出以工作流为核心的PDM系统体系结构;在此基础上,为该PDM系统在轴承行业的实施提供方案.     

离合器摩擦片的修复

工程机械离合器摩擦片的作用是传递动力和切断动力。现以WL83LD-1型离合器为例,其主动摩擦片的材料为30CrMnSiA,调质处理后的硬度为HRC26-28。由于摩擦片在高速、高温和高频率离合下工作,在一个中修期内,摩擦片因磨损报废的比例很高,摩擦片耗量非常大,造成很大的经济损失。     

通用CAPP系统中制造资源管理系统的研究

分析了通用CAPP系统对制造资源的要求，建立了制造资源模型，并介绍了所开发的制造资源定制工具平台，对不同的制造环境，运行该工具可以方便地实现制造资源的定制。     

高强度硒-铜-磷系常温发黑工艺及应用研究

论述硒、铜、磷系高强度常温发黑液的配方、主要技术指标、常温发黑工艺和发黑成膜原理。利用硒、铜、磷盐和专门研制的添加剂和配方 ,研制的高强度常温发黑液和工艺 ,进行机械零件的常温发黑 ,膜层性能、附着力、耐磨性和耐蚀性好