Features of realization of intelligent system of analysis and forecasting of space vehicles

Рассматриваются методы и средства по созданию системы прогнозирования нештатных ситуаций на борту пилотируемых космических аппаратов. Для решения задач система использует концептуальную и математическую модели космического аппарата. Применение системы поможет специалистам главной оперативной группы управления своевременно обнаруживать отклонения от штатного режима работы и принимать соответствующие меры.The purpose of the study is designing an intelligent system for supporting safety and reliability at the operation stage of a manned space vehicle

Internal Stress Evolution and Subsurface Phase Transformation in Titanium Parts Manufactured by Laser Powder Bed Fusion—An In Situ X‐Ray Diffraction Study

Laser powder bed fusion (LPBF) is a metal additive manufacturing technology,which enables the manufacturing of complex geometries for various metals andalloys. Herein, parts made from commercially pure titanium are studied usingin situ synchrotron radiation diffraction experiments. Both the phase transformationand the internal stress buildup are evaluated depending on the processingparameters. For this purpose, evaluation approaches for both temperatureand internal stresses from in situ diffraction patterns are presented. Four differentparameter sets with varying energy inputs and laser scanning strategiesare investigated. A combination of a low laser power and scanning speed leads toa more homogeneous stress distribution in the observed gauge volumes. Theresults show that the phase transformation is triggered during the primarymelting and solidification of the powder and subsurface layers. Furthermore, thestress buildup as a function of the part height during the manufacturing processis clarified. A stress maximum is formed below the part surface, extending intodeeper layers with increasing laser power. A temperature evaluation approach forabsolute internal stresses shows that directional stresses decrease sharply duringlaser impact and reach their previous magnitude again during cooling