拉深工艺中对各向异性的利用

在冷冲压生产中,圆筒形制件的拉伸是成形工艺的最基本形式。因而对圆筒形件深拉伸的研究就成为板料冲压技术中的重要研究课题。这种课题之一就是——深拉伸杯形件的凸耳现象用于制造不带凸缘和带凸缘的圆筒形拉伸件的毛坯形状,一般都采用圆形的。其理由无非是为了使拉伸后的高度均匀,同时在成形过     

Reaction process of monazite and bastnaesite mixed rare earth minerals calcined by CaO-NaCl-CaCl2

The decomposition reactions of monazite and bastnaesite mixed rare earth minerals calcined by CaO-NaCl-CaCl2 were studied by means of TG-DTA and XRD. The results show that the process of the minerals decomposed by CaO involves two steps. The first step occurs in the temperature range of 425-540 ℃, and the main reactions are bastnaesite decomposition, i.e. REOF reacts with CaO to produce RE2O3 and CaF2, and Ce2O3 is oxidized to CeO2. During this step, CaCO3 is formed at about 500 ℃. The second step takes place in the temperature range of 610-700 ℃, and the reactions are monazite decomposition into RE2O3, Ca5F（PO4）3 and Ca3（PO4）2 by CaO and CaF2. In this process, the decomposition ability is improved because CaO from CaCO3 decomposing has high chemical activity. In calcining process, the new formed Ca5F（PO4）3 restrains fluorine that can escape in form of gaseous compound. The decomposition ratio of the mixed rare earth minerals reaches 90.8% at 700 ℃.     

闭式机械压力机的安全调模法

闭式机械压力机在安装调整冲模时,特别是在前次试调新的冲模时,非常容易发生意外的安全事故.不少人习惯于采用“下死点调模法”,即把冲模拉入压力机的工作台后,使滑块寸动下行至接近冲模上底面,看滑块下死点是否符合冲模的闭合高度.这种下死点调模法,即使经验丰富和操作小心,也还是会发生“闷车”、连杆折断或蹩弯之类设备事故,也     

计算机技术在大学校园网络中的应用

二十一世纪是一个计算机技术与信息技术的时代,随着我国社会经济与科学技术的不断发展,计算机技术也得到了越来越广泛的应用,如今在我国各行各业的建设当中都已离不开计算机技术的支持。大学是培养人才的基地,大学校园网络建设是大学校园建设中的一大重要项目,而计算机技术在大学校园网络的建设当中正起着关键性的作用。本文主要阐述了计算机技术在大学校园网络中的应用,并就如何才能更好地运用计算机技术来建设大学校园网络提出一定的建议。     

基于计算智能的电站锅炉燃烧优化控制

燃烧优化是提升电站锅炉效率降低污染物排放的有效途径;计算智能是目前实现燃烧过程建模及优化的重要手段.本文综述了各种计算智能算法在电站锅炉燃烧优化控制中研究成果,分别对其技术特点和不足进行了分析,并提出了燃烧优化技术的发展方向和前景,对从事该方面的研究人员有一定参考价值.     

Improvement of wear resistance of AZ31 and AZ91HP by high current pulsed electron beam treatment

The surface modification of magnesium alloys （AZ31 and AZ91 HP） was studied by a high current pulsed electron beam（HCPEB）. The results show that the cross-sectional microhardness of treated samples increases not only in the heat affected zone（ HAZ）, but also beyond HAZ, reaching over 250μm. This is due to the action of quasi-static thermal stress and the shock thermal stress wave with materials, which result in its fast deformation on the surface layer and so increases microhardness. For the AZ91HP alloy, a nearly complete dissolution of the intermetallic phase Mg17Al12 is observed, and a super-saturated solid solution forms on the re-melted surface, which is due to the solute trapping effect during the fast solidification process. Measurements on sliding wear show that wear resistance is improved by approximately 5.6 and 2.4 times for the AZ31 and AZ91HP respectively, as compared with as-received samples.     

高压软管装配模

“高压软管”是在胶层中夹有钢丝网的橡胶管,供在液压传动中向运动的油缸或其他液压装置输送高压油用。我厂生产的东方红28型拖拉机上提升、下降农具用的悬挂系统,就是采用高压软管来向油缸供油的。此外,在推土机、挖掘机、装卸机及一般的机械设备中也被广泛地加以采用。     

鞍山钢铁工业循环经济发展模式选择

从鞍山钢铁工业的实际情况出发,提出了建设混合型钢铁生态工业园的鞍山钢铁工业循环经济发展模式。从园区内企业分类、种群共生关系分析、行业网络耦合、生态产业链设计和企业生态位分析等方面对鞍山钢铁工业生态系统结构进行了设计。     

速凝成晶-烧结法制备磁致伸缩材料的研究

用速凝成晶方法制造Tb0.30Dy0.70We1.80合金薄片，合金薄片经过制粉、磁场取向压制成型和烧结制造磁致伸缩材料。结果表明：制造的速凝成晶Tb0.30Dy0.70We1.80合金薄片的显微组织以柱状晶为主。对速凝成晶Tb0.30Dy0.70We1.80合金粉末磁场取向后，烧结样品〈111〉晶向的取向程度提高；对速凝成晶Tb0.30Dy0.70We1.80合金薄片热处理后，烧结样品的磁致伸缩性能明显好于未热处理速凝成晶Tb0.30Dy0.70We1.80合金粉末的烧结样品。     

钢铁工业循环经济实践分析与发展途径

从循环经济理论研究的一般性问题出发，分析了钢铁工业循环经济的实践情况；阐述了钢铁工业循环经济发展的总体思路；设计了多条钢铁工业生态产业链；提出了铁素高效利用、水循环利用、能量梯级利用、固体废弃物资源化利用、信息集成利用的钢铁工业发展循环经济的实施途径。