TiN-matrix composite coating was prepared on 45# steel by reactive high-velocity oxy-fuel （HVOF） spraying. Its microstructure, phase composition, micro-hardness, corrosion resistance in 3.5% NaC1 solution and wear r...TiN-matrix composite coating was prepared on 45# steel by reactive high-velocity oxy-fuel （HVOF） spraying. Its microstructure, phase composition, micro-hardness, corrosion resistance in 3.5% NaC1 solution and wear resistance were analyzed. The results suggest that the TiN-matrix composite coating is well bonded with the substrate. The micro-hardness measured decreases with the increase of applied test loads. And the micro-hardness of the coating under heavy loads is relatively high. The TiN-matrix composite coating exhibits an excellent corrosion resistance in 3.5% NaC1 solution. The corrosion potential of coating is positive and the passivation zone is broad, which indicates that the TiN-matrix composite coating is stable in the electrolyte and provides excellent protection to the substrate. The wear coefficient of the coating under all loads maintains at 0.49-0.50. The wear mechanism of the coating is revealed to be three-body abrasive wear. Yet the failure forms of TiN-matrix composite coating under different loads have an obvious difference. The failure form of coating under light loads is particle spallation due to the stress concentration while that of coating under heavy loads is crackin~ between inter-lamellae.展开更多
SiO2 in calcium aluminate slag exists in the form of γ-2CaO·SiO2 which is more stable than β-2CaO·SiO2. However, it is decomposed by sodium carbonate solution during leaching process, leading to the second...SiO2 in calcium aluminate slag exists in the form of γ-2CaO·SiO2 which is more stable than β-2CaO·SiO2. However, it is decomposed by sodium carbonate solution during leaching process, leading to the secondary reaction. The extent of secondary reaction and reaction mechanism of calcium aluminate slag were studied using XRD. The results show that the decomposition rate of γ-2CaO·SiO2 increases with the increase in leaching time and sodium carbonate concentration. The main products of secondary reaction are the mixture of hydrogarnet and sodium hydrate alumina-silicate. SiO2 concentration rises firstly and then drops with the increase of leaching temperature. XRD results indicate that the stable product of secondary reaction at low temperature is hydrogarnet. But hydrogarnet is transformed into sodium hydrate alumina-silicate at high temperature.展开更多
为了提高焊接机器人的编程效率并保证焊接质量,对机器人运动学仿真和控制系统进行了研发。首先采用D-H参数法建模并对焊接机器人进行了正逆运动学求解,然后通过构建焊缝坐标系的方法对相贯线的自动路径规划进行了研究,并利用PC SDK与机...为了提高焊接机器人的编程效率并保证焊接质量,对机器人运动学仿真和控制系统进行了研发。首先采用D-H参数法建模并对焊接机器人进行了正逆运动学求解,然后通过构建焊缝坐标系的方法对相贯线的自动路径规划进行了研究,并利用PC SDK与机器人控制器进行通信。基于Visual Studio C#平台结合OpenGL实现了机器人的运动学仿真、自动路径规划和远程弧焊控制功能。最后通过RobotStudio对该系统的基本功能进行了验证,结果表明系统准确可靠且满足焊接机器人的工作要求,较大地提高了作业效率,为机器人仿真和远程控制系统的开发提供了解决方案。展开更多
基金Project(KFJJ10-15M) supported by the Open Fund of State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology,ChinaProject(E2013208101) supported by the Nature Science Fund of Hebei Province,China+1 种基金Project(Z2012100) supported by Colleges and Universities Science and Technology Research Fund of Hebei Province,ChinaProject supported by the Outstanding Youth Fund of Hebei University of Science and Technology,China
文摘TiN-matrix composite coating was prepared on 45# steel by reactive high-velocity oxy-fuel （HVOF） spraying. Its microstructure, phase composition, micro-hardness, corrosion resistance in 3.5% NaC1 solution and wear resistance were analyzed. The results suggest that the TiN-matrix composite coating is well bonded with the substrate. The micro-hardness measured decreases with the increase of applied test loads. And the micro-hardness of the coating under heavy loads is relatively high. The TiN-matrix composite coating exhibits an excellent corrosion resistance in 3.5% NaC1 solution. The corrosion potential of coating is positive and the passivation zone is broad, which indicates that the TiN-matrix composite coating is stable in the electrolyte and provides excellent protection to the substrate. The wear coefficient of the coating under all loads maintains at 0.49-0.50. The wear mechanism of the coating is revealed to be three-body abrasive wear. Yet the failure forms of TiN-matrix composite coating under different loads have an obvious difference. The failure form of coating under light loads is particle spallation due to the stress concentration while that of coating under heavy loads is crackin~ between inter-lamellae.
基金Project(51104053)supported by the National Natural Science Foundation of ChinaProject(E2012208047)supported by the Natural Science Foundation of Hebei Province,China
文摘SiO2 in calcium aluminate slag exists in the form of γ-2CaO·SiO2 which is more stable than β-2CaO·SiO2. However, it is decomposed by sodium carbonate solution during leaching process, leading to the secondary reaction. The extent of secondary reaction and reaction mechanism of calcium aluminate slag were studied using XRD. The results show that the decomposition rate of γ-2CaO·SiO2 increases with the increase in leaching time and sodium carbonate concentration. The main products of secondary reaction are the mixture of hydrogarnet and sodium hydrate alumina-silicate. SiO2 concentration rises firstly and then drops with the increase of leaching temperature. XRD results indicate that the stable product of secondary reaction at low temperature is hydrogarnet. But hydrogarnet is transformed into sodium hydrate alumina-silicate at high temperature.
文摘为了提高焊接机器人的编程效率并保证焊接质量,对机器人运动学仿真和控制系统进行了研发。首先采用D-H参数法建模并对焊接机器人进行了正逆运动学求解,然后通过构建焊缝坐标系的方法对相贯线的自动路径规划进行了研究,并利用PC SDK与机器人控制器进行通信。基于Visual Studio C#平台结合OpenGL实现了机器人的运动学仿真、自动路径规划和远程弧焊控制功能。最后通过RobotStudio对该系统的基本功能进行了验证,结果表明系统准确可靠且满足焊接机器人的工作要求,较大地提高了作业效率,为机器人仿真和远程控制系统的开发提供了解决方案。
