调整与控制施工技术研究与应用

对结构进行调整与控制的施工主要是通过调整或控制结构的变形来完成,使结构施工过程中的变形及内力状态始终处于有效的可控状态。目前通过张拉钢绞线索向结构施加预变形或平衡结构荷载的主动调控途径具有较强的研究及应用推广价值,并已成功应用于一些工程中。     

轮胎钢丝帘线技术发展

简述国内外轮胎的发展历史、钢丝帘线作为子午线轮胎骨架材料的独特性能优势及我国钢丝帘线行业的发展历程;结合有限元分析结果介绍子午线轮胎对胎体和带束层钢丝帘线的功能需求以及轮胎可持续发展的要求;重点阐释了钢丝帘线在强度、结构、预变形及镀层方面的主要发展趋势。     

钢丝绳捻制中预变形器和后调直器的研制

以捻制8×19S-13电梯用钢丝绳为例,对8/450合绳设备的预变形器和后调直器进行重新设计和制造,将预变形器改为卧式锥形结构,后调直器由5轮3组改为7轮4组。工艺工装改进后,进行样品试验和批量生产,检测显示各项技术指标较改进前有较明显的提高。     

预变形对挤压态Mg-6%Zn-1%Mn镁合金时效硬化效应和力学性能的影响(英文)

采用显微硬度测试、拉伸试验、金相观察和TEM观察,研究冷塑性变形对Mg-6%Zn-1%Mn(ZM61)合金时效硬化和力学性能的影响。在420℃固溶处理1h后,对ZM61挤压棒材试样进行室温拉伸变形,塑性应变有3种:0、5%和10%,预变形后再进行人工时效。时效硬化曲线表明:预变形可以显著加快硬化速率且提高峰值硬度;然而,当应变量由5%增加到10%后,峰值硬度并未增加。室温拉伸性能表明:预变形量增加,屈服强度和抗拉强度增加,伸长率略有降低,且屈服强度的增加幅度大于抗拉强度的。金相组织观察表明:当预变形应变量为5%时,金相组织中未观察到孪晶;预变形10%的组织中出现了大量的孪晶。TEM观察表明:预变形可以增加峰时效态组织中β1′杆状相的数量。     

The Effect of Pre-Deformation at Elevated Temperatures on the Microstructure and Hardness of Boron Steel 22MnB5

To investigate the effects of the pre-deformation and deformation temperature on the microstructure and hardness of boron steel 22MnB5,isothermal tensile tests were carried out on the Gleeble 3800 system when the temperatures are 700℃,750℃,800℃,respectively.Three specimens were employed to obtain different deformation levels at each temperature.The cooling rate before and after deformation was 30℃/s.Then the microstructures of the specimens were observed and the harness of each specimen was measured.The results show the martensitic fraction decreases and the ferrite fraction increases with decreasing the deformation temperature or increasing the deformation level.The specimens deformed at higher temperature have greater hardness.The hot plastic deformation of austenite shortens the incubation period of ferrite transformation and accelerates the transformation rate.In addition,the isothermally holding time is longer in the case of a larger deformation amount,more austenite will transform to ferrite.Especially,the specimen deformed at 700℃ and with large deformation has almost full massive ferrite microstructure with larger size.     

边界初始变形的简支复合材料层板

考究了复合材料蒙皮与筋条铆接问题。提出了边界有初始小变形的四边简支矩形层板这一力学模型。关于这一力学模型得到了简洁明了的精确解。其解构构造简单，某些参数有表可查，使于工程中设计和较核之用。     

周向波度密封环预变形平面研磨加工中的变形分析

端面周向波度密封是一种非接触机械密封,它具有泄漏低、刚度大和寿命长等优点,在核主泵和透平机械等旋转机械密封中有很好的应用前景。周向波度密封环端面面形非常复杂,加工极为困难。提出一种周向波度密封环的预变形平面研磨加工方法,并对其中最为关键的预变形过程进行了分析。通过对预变形过程中密封环变形特性的有限元分析,揭示了预紧力和密封环端面变形的关系,通过周期性反向扭矩的作用获得了满足要求的表面预变形。通过预变形夹具的研制和平面研磨工艺研究,完成了周向波度密封环的加工,证明了预变形平面研磨加工方法加工周向波度密封环的可行性。     

Non—equilibrium Segregation of boron on grain boundary in Fe—30% Ni alloy

The moving boundary non-equilibrium segregation during recrystallization and the influence of pre-deformation in Fe-30% Ni Alloy at 1000℃ was investigated by the PTA9Particle tracking autoradiography)technique,optical and electron microscopy.The results indicated that intensity of bron segregation on moving boundary after different deformation is concerned with the pre-deformation degree and the moving speed of the boundary,The TEM(transmission electron microscopy)result showd that the dislocation density nearby the moving boundary increase obviously.The phenomena are discussed by the widening grain boundary mechanism.     

Effect of Pre-deformation on Abnormal Segregation of Grain Boundary during Recrystallization Process

The softening rates of Fe-30%Ni alloy containing boron after 10% and 40% deformation at 1000℃ have been measured by a method of interrupted compression, the recrystallization process has also been evaluated.The moving velocity of the boundary of new recrystallizing grain which was growing into the deformed grans has been calculated semi-quantitatively. By means of PTA technique, the abnormal segregation phenomenon on the moving boundary during recrystallization and the influence of pre-deformation have been investigated and the amount of B segregation on moving grain boundaries has been measured .Results indicate that the abnormal segregation of boundaries, when the new grains are growing, is concemed with the pre-deformation and the moving velocity of the bourdaries. This phenomenon is discussed by the gtain boundary widening mechanism.     

预变形结合人工时效对Al-Mg-Si合金力学性能的影响

研究预变形结合人工时效处理对AA6060铝合金强度和韧性的影响。对经过均匀化热处理和挤压加工的AA6060铝合金进行固溶处理,然后对材料实施0-10%的预变形并再进行时效处理或者在人工时效过程中进行同步变形。通过对不同时效处理后的合金的显微硬度和拉伸性能分析,发现预变形对材料的时效行为和力学性能有显著影响,它可以使合金的时效速度明显加快。比较预变形和同步变形对人工时效的影响发现,同步变形结合人工时效可以使该合金在更短的时间内得到更好的力学性能。对两种变形对时效行为的影响机理进行了探讨。