风力发电装备制造中焊接技术的新发展（三）

本文系统地介绍了现代风力发电装备制造中焊接生产工艺流程，论述了相关焊接工艺方法及焊接装备的最新发展，详细阐明了关键自动化焊接设备的结构特点和技术特性以及风电装备主要部件的先进焊接工艺，展望了风力发电装备制造业的发展前景。     

风力发电装备制造中焊接技术的新发展（四）

本文系统地介绍了现代风力发电装备制造中焊接生产工艺流程，论述了相关焊接工艺方法及焊接装备的最新发展，详细阐明了关键自动化焊接设备的结构特点和技术特性以及风电装备主要部件的先进焊接工艺，展望了风力发电装备制造业的发展前景。     

高能加速器漂移管的电子束焊接

漂移管是高能加速器腔体中的重要部件,对这种要求精密装配的焊接部件,采用电子束焊接具有很大的意义。本文对漂移管的结构及焊接技术条件、铜-铜外环缝的焊接、铜-蒙乃尔内环缝的焊接以及焊接生产问题作了详细的论述。采用电子束焊接的57支漂移管中,废品率仅占1.7％,达到了国外同类产品的水平。     

运用反变形方法合理控制铝合金车顶焊接变形

结合铝合金车顶焊接具体实例,分别对焊接变形的产生及运用反变形方法控制焊接变形做出分析,收到了一定效果。该研究对此类结构的铝合金车体大部件焊接变形的控制有一定的实际应用意义。     

矿山机械拉铲基座的制作及焊接工艺研究

文中通过对矿山机械拉铲基座制作顺序及焊接工艺的改进研究,将原先整体制作的结构分解成若干部件,再结合合理的焊接工艺和严格的过程控制,配备一定的辅助工装,解决了焊接应力集中、焊接变形、裂纹等焊接缺陷问题,提高了基座结构的制作质量。     

轨道辆车体铝合金部件自动焊设备研制

主要介绍了在轨道车辆铝合金部件焊接生产过程中所采用的龙门自动焊接专机和机器人焊接工作站的结构特点及应用状况.概括了适合进行自动化焊接生产的铝合金产品及工装条件,对系列龙门自动焊接专机的机械结构、操作系统、焊接和跟踪系统进行了一定的说明.同时还对机器人自动化焊接过程中焊枪空间呵达性、重复定位精度、焊缝类型、空间工作安全等...     

核能设备的焊接技术

本文综述了核能设备的焊接特点，各部件的具体焊接方法及焊接质量的保证措施，展示了高水平焊接技术的系统性，严密性及科学性。     

大型复杂结构件的焊接应力与变形控制

以数控双柱立式车铣复合机床的焊接部件横梁为例,分析了影响横梁焊接应力及变形的制造因素和结构因素.以此分析为依据,对产品零部件的准备、组装、焊接等每一道工序进行工艺方案优化;总结出合理的装配工艺、减小热输入并提高其稳定性、改善焊接工艺等措施,对数控双柱立式车铣复合机床的横梁焊接部件的焊接应力及变形进行控制:进而总结出类似...     

大型管式褐煤干燥机管板制造工艺及质量控制

管式褐煤干燥机两端管板采用圆形特厚钢板制作而成,且钢板表面钻有大量圆孔,部件质量大。该结构主要依靠焊接及机加工完成,焊缝数量多,焊接任务量大,部件加工及部件之间组装精度要求高,对制造质量要求非常严格。分析某大型管式褐煤干燥机管板结构,总结出一套合理的焊接、机加工工艺以及对关键部位的质量控制措施,为其他大型旋转机械设备的制造提供参考和借鉴。     

圆形料场堆取料机中心立柱支腿组装及焊接工艺

中心立柱支腿作为中心立柱旋转的主要维稳受力部件,其结构形式复杂,焊缝受力大,在制造过程中如何进行各部件组装、焊接成为中心立柱支腿制造及质量保证的关键。本文通过分析圆形料场堆取料机中心立柱支腿的结构特点,重点分析了立柱支腿在制造过程中的组装及焊接工艺。实践证明,该工艺可有效地控制立柱支腿的焊接变形,保证焊接质量,从而为圆形料场堆取料机的稳定、安全运行奠定基础。     

胫骨生物陶瓷复合材料的微结构增韧机理

扫描电镜观察显示胫骨是一种由羟基磷灰石和胶原蛋白组成的自然生物陶瓷复合材料.羟基磷灰石具有层状的微结构并且平行于骨的表面排列.观察也显示这些羟基磷灰石层又是由许多羟基磷灰石片所组成,这些羟基磷灰石片具有长而薄的形状,也以平行的方式整齐排列.基于在胫骨中观察到的羟基磷灰石片的微结构特征,通过微结构模型分析及实验,研究了羟基磷灰石片平行排列微结构的最大拔出能.结果表明,羟基磷灰石片长而薄的形状以及平行排列方式增加了其最大拔出能,进而提高了骨的断裂韧性.     

面向零件形状的计算机图形库的开发

论述了CAD技术中参数化设计的三种建模方法，重点介绍了基于特征的参数化建模原理。在此基础上，分析机械设计中的机构结构，归纳出其零件的几何特征构成。设计了机构CAD图形库，并提出了该图形库生成步骤和人机交互界面。     

FeCrAIW电弧喷涂层组织的致密化研究

采用激光辐照对FeCrAlW电弧喷涂层的组织进行致密化处理,借助扫描电镜和X衍射对涂层的组织进行了分析.测试了涂层的显微硬度.结果表明:涂层组织致密度提高,孔隙率明显降低.随着激光扫描速度的增加,涂层的显微硬度降低.在较低的扫描速度下,涂层与基体之间形成互熔区,涂层与基体之间产生良好的冶金结合.     

Prospects of the Use of Synergetic Approach to Solution of Problems of the Science of Nanomaterials

A synergetic approach to solution of problems of self-controlled synthesis of nanostructures and creation of self-organizing nanotechnologies is considered in connection with the superproblem of creation of materials with functional properties resembling those of biosystems. __________ Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 7, pp. 55 – 61, July, 2005.     

Kinetics of the oxidation of metals — Influence of self-diffusion of metal

The importance of the self-diffusion of a metal during its oxidation by a gas is treated for the cases of nonstoichiometric oxides having either interstitial cation or cation vacancies. We have established a general relationship for the reaction rate when a mixed diffusion process occurs. From this relationship, we have shown that the pressure dependence can be different, according to whether the rate-determining process is the self-diffusion through the metal or through the product.     

Features of formation of the structure in production of blanks of disks of heat-resistant nickel alloys

Conclusions To provide a high level of mechanical properties in wrought blanks of cast ÉP741NP and ÉP962 alloys it is necessary to form controlled structures. A necklace-type structure formed in homogenizing isostatic treatment, subsequent thermomechanical working including alternation of the operations of deformation in the (+)-area and recrystallization anneals, and final heat treatment is preferable. The temperature conditions of all stages of thermomechanical working are strictly controlled, especially the final operation of deformation and heating for hardening. To eliminate hardening cracks and distortions it is necessary to use molten salts at t=600°C as quenchants. The use of multiple production operations makes it possible to significantly reduce the structural inhomogeneity related to inhertance of the original dendritic structure. However, the structure of the final semifinished product is nevertheless characterized by a difference in occurrence of the processes of polygonization and recrystallization between the former dendritic cells and the interdendritic spaces in deformation and heat treatment.To obtain structurally homogeneous blanks for gas turbine engine parts it is necessary to use basically new methods of remelting such as vacuum double electrode remelting and electron beam remelting with an intermediate vessel.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 12, pp. 25–29, December, 1991.     

Ab-initio calculation of enthalpies of formation of intermetallic compounds and enthalpies of mixing of solid solutions

A large number of ab-initio calculations of energies of formation of intermetallic compounds have been performed in the last 15 years. The currently used methods are listed. The paper presents a review of the aluminium based compounds which have been studied. Comparisons of calculated and experimental enthalpies of formation are provided for aluminim-3d and-4d transition metal alloys at equiatomic composition. The modelling of the enthalpies of mixing of solid solutions based on a given lattice is described.