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董寅生%沈军%杨英俊%李庆春 《宇航材料工艺》2000,30(2):1-6
综述了快速凝固耐热铝合金中金属间化合物弥散相的研究现状,介绍了常见耐热铝合金中存在的弥散相,快速凝固工艺对弥散相形成的影响和弥散相的热稳定性及其影响因素,简要概述了弥散相的数量,分布,形状等和耐热铝合金常温和高温力学性能之间的关系。 相似文献
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目前,3D打印技术在各行业得到了广泛的应用,探讨和研究3D打印技术在空空导弹中的应用具有重要的意义.简要介绍了3D打印技术概念、原理和材料,重点介绍了水冷板进行3D打印加工过程,打印成功的水冷板通过检验、加工、装配,满足结构设计要求.3D打印能够缩短水冷板加工周期,降低加工成本. 相似文献
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Regarding the rapid compensation of the influence of the Earth' s disturbing gravity field upon trajectory calculation,the key point lies in how to derive the analytical solutions to the partial derivatives of the state of burnout point with respect to the launch data.In view of this,this paper mainly expounds on two issues:one is based on the approximate analytical solution to the motion equation for the vacuum flight section of a long-range rocket,deriving the analytical solutions to the partial derivatives of the state of burnout point with respect to the changing rate of the final stage pitch program;the other is based on the initial positioning and orientation error propagation mechanism,proposing the analytical calculation formula for the partial derivatives of the state of burnout point with respect to the launch azimuth.The calculation results of correction data are sim ulated and verified under different circumstances.The simulation results are as follows:(1) the accuracy of approximation between the analytical solutions and the results attained via the difference method is higher than 90%,and the ratio of calculation time between them is lower than 0.2%,thus demonstrating the accuracy of calculation of data corrections and advantages in calculation speed;(2) after the analytical solutions are compensated,the longitudinal landing deviation of the rocket is less than 20 m and the lateral landing deviation of the rocket is less than 10 m,demonstrating that the corrected data can meet the requirements for the hit accuracy of a long-range rocket. 相似文献