一种计算冲裁力的新方法

设计冷冲模,按传统方法计算出的冲裁力往往偏大,进而冲压力偏大,有时可能会导致超过现有压力机的吨位。文中介绍了一种计算冲裁力新方法,按新方法设计的冷冲模,在不改变模具零件结构的条件下能降低冲裁力,也能为冲压设备的型号提供更多的选择余地。通过一实例对新方法进行了验证,结果证明新方法切实可行,可为冷冲模设计人员提供参考。     

论供暖系统的分户计量与集中控制

针对当前不合理的供暖收费制度,阐述了按热量收费的必要性,分析了现有分户计量的基本方法、应注意的问题,以及供热系统的集中控制,讨论了分户计量和集中控制协调运行的关系.在实际应用中,应保证二者协调运行,节约能源.     

TiO2—Al—B系反应烧结制备的复相陶瓷和原位Al基复合材料

采用反应烧结方法，利用ＴｉＯ２，Ａｌ和Ｂ粉末间的放热反应的较低的温度下制备Ａｌ２Ｏ３－ＴｉＢ２复相陶瓷和原位生长Ａｌ２Ｏ３和ＴｉＢ２弥散粒子增强Ａｌ复合，Ａｌ２Ｏ３－ＴｉＢ２复相陶瓷是密度ρ－０．８的多孔体，由尺寸小于２μｍ，在基体中呈现均匀分布，没有发现Ａｌ３Ｔｉ生成，这种原位Ａｌ基复合材料具有优于ＳｉＣｗ／Ａｌ复合材料的强度。     

Microstructure of TiB Whisker Reinforced Ti Matrix Composite

The composite of Ti matrix with TiB whisker reinforcement has been successfully fabricated. The content of TiB whisker in Ti matrix can reach about 30 vol. pct. Metallographic examination,morphology and microstructure of TiB whisker, interface structure between TiB whisker and Ti matrix were investigated using optical microscope, SEM, TEM and HREM technology. The diameter distribution of TiB whisker is from 0. 1 μm to 3.5 μm and the aspect ratio of TiB whisker is from 10 to 20. The cross-section of whisker is generally polygon. Because of good compatibility between TiB whisler and Ti matrix it is identified that there is no obvious interaction of Ti matrix with Ti B reinforcement and TiB whisker reinforced Ti matrix composites have excellent elevated properties.