Evaluation of the superplastic formability of SP-inconel 718 superalloy

The superplastic formability of SP- lnconel 718 superalloy was evaluated using the argon blowing method. Relationships among superplastic forming parameters (forming temperature, argon pressure, and forming time) and specific dome height (dome height/workpiece diameter) were investigated, as were changes in material properties after superplastic forming. Experimental results showed the optimum forming temperature range for SP- lnconel 718 to be between 975 and 995 °C. During the superplastic forming process, 5- phase precipitates formed at grain boundaries and limited the grain growth, which is considered beneficial for superplastic deformation. On the other hand, increasing the forming deformation also increased the formation of cavities, which can be attributed to the existence of niobium- rich inclusions. This degraded the superplasticity of the superalloy. Electrochemical tests showed that the corrosion resistance of SP- lnconel 718 after superplastic forming worsened because of the existence of both S- phase precipitates and niobium- rich inclusions.     

基于人工智能的钛合金热变形工艺参数优化

在深入分析热变形工艺参数对Ti-15-3合金显微组织及成形载荷的影响的基础上,以变形温度、变形程度和变形速率等热变形工艺参数作为设计变量,以显微组织和成形力的最佳综合为目标,建立了该合金热塑性成形工艺参数的多目标优化数学模型。以显微组织参数和成形力的人工神经网络预测模型作为优化算法的知识源,将人工神经网络与修正的遗传算法相结合,对Ti-15-3合金的热塑性成形工艺参数进行优化。结果表明,提出的修正的遗传算法是有效的,采用将其与人工神经网络相结合的方法对钛合金的热塑性成形工艺参数进行优化是可行的。     

共轨喷油器参数优化研究

现代柴油机采用共轨喷油器已经成为其必不可少的环节,对共轨喷油器的工作特性研究具有重要意义。通过对共轨喷油器的主要结构进行数学建模,得出影响喷油器喷油特性和泄漏特性的结构参数。利用AMESim软件对共轨喷油器的工作过程进行仿真分析,得出单个结构参数对喷油率和泄漏量的影响,由此选择合理范围的结构参数进行正交试验,选用综合平衡法对指标进行评价。得出最优结构参数,优化方案在提高喷油器喷油率以及降低泄漏方面有明显的效果。     

交流电量的实时检测技术及实现

针对电力参数的实时高精度检测难题，介绍了一种用于交流电量(电压、电流、有功功率、功率因数、频率等)的采用双速率同步交流采样算法的实时自动检测技术。该系统基于16位单片机，以交流电量为检测对象，通过对工频的跟踪检测和双速率同步交流采样算法，提高系统的检测精度。文中阐述了该技术的原理、硬件实现和软件设计。经过实践证明，该技术在电力系统的智能检测中有很大的应用前景。     

细丝窄间隙埋弧焊工艺参数寻优

主要研究A105钢小直径焊丝埋弧焊时,电弧电压、焊接电流和焊接热输入对焊缝成形的影响.在反复调节不同焊接工艺参数进行平板表面堆焊试验的基础上,得出保证最佳焊缝成形时,电弧电压与焊接电流的关系,以及它们的最佳匹配值,并量化了焊接热输入与焊缝宽度之间的关系.为窄间隙埋弧焊提供了有益的经验,同时也为小直径焊丝焊接工艺的全面优化奠定基础.     

基于CAE技术的汽车前保险杠成型工艺优化研究

介绍了利用CAE技术优化汽车保险杠的浇口设置,在优化方案的基础上,结合经验设计冷却系统,通过正交试验的方式确定保险杠成型工艺参数对翘曲变形的影响程度,得出最佳的工艺参数组合,用以指导生产实践。     

Influence of process parameters on thermal-rate treatment of ZA42 alloy

Sand casting process and directional solidification technique combining thermal-rate treatment(TRT) were used. The influence of process parameters on TRT was investigated according to the values of impact toughness. At the same time, the mechanism of TRT was discussed. The results showed that TRT can improve the impact toughness of this alloy, while the hardness is basically constant. The time of heat preservation should not be more than 5min. Different forms of cooling intensification additive have different effects among which the zinc ingot solidified in graphite mold is the best one that can improve impact toughness of samples by more than 80%. With increasing the cooling temperature, the value of α(Al) crystal lattice constant increases. The element Sb has negative effect on TRT.     

离心泵性能参数的自动测定和自动控制

通过将计算机技术应用于离心泵性能参数的研究，实现了离心泵性能参数的自动测定和自动控制。     

Determination of the solubility parameter of poly(ethylene oxide) at 25°C by gas-liquid chromatography

The solubility parameter of poly(ethylene oxide) at 25°C has been determined using the method developed by DiPaola-Baranyi and Guillet, by the extrapolation of the values of the interaction parameter χ, at high temperatures, ranging from 70°–90°, 90°–110° and 110°–130°C down to 25°C. The values of the solubility parameter obtained, depending on the temperature ranges employed, are 9.8, 9.9 and 10.1, respectively.     

低温等离子体处理纤维素纤维的机理和性能研究

本文应用不同技术参数的低温等离子体对Lyocell纤维进行处理,借助SEM等手段对其表面特征和物理性能进行研究,通过化学热力学和化学动力学,对反应机理做了研究和分析,证明了通过这种新型手段对Lyocell纤维进行接枝和改性的可行性和优越性,并针对Lyocell纤维的一些相关性能进行了处理前和处理后的比较,结果表明低温等离子体处理后的Lyocell纤维在不降低物理机械性能的同时很大程度上减少了纤维的原纤化。