In order to automatically detect the corrosion on the piston rod of hydraulic hoist of hydropower station and find the location of corrosion conveniently and accurately,a piston rod defect detection robot based on mac...In order to automatically detect the corrosion on the piston rod of hydraulic hoist of hydropower station and find the location of corrosion conveniently and accurately,a piston rod defect detection robot based on machine vision was developed.Firstly,the structure of the robot is presented,the detection system introduces the data collection process in the process of image processing,using a laser camera to capture image information.After the image preprocessing,cascade filter and morphological images after operation,the image information of gradient data,the depth of the defect data is extracted.To acquire the information of image defects in concave and convex,after using the RGB color image information acquisition defects the camera,HSV space separation and median filter and morphological processing are used to extracti defects in the image color information.Finally for defect information coding for quad,through comprehensive information for defect recognition and using QT development the human-computer interaction interface is developed,which can realize the reality and statistics of the robot′s motion control and defect information.Through the experimental verification of the robot′s performance,it is proved that the reliability of the robot′s motion and the accuracy of defect identification meet the design goal.展开更多
The segregation of Cu and Ni in a 17-4PH stainless steel piston rod has been confirmed to be responsible for the cracking after heat treatment.Further investigation showed that the segregation zone was composed of thr...The segregation of Cu and Ni in a 17-4PH stainless steel piston rod has been confirmed to be responsible for the cracking after heat treatment.Further investigation showed that the segregation zone was composed of three layers,namely the fine grain martensitic layer,the coarse grain martensitic layer and the coarse grain austenitic layer from the matrix to the crack surface.Three button ingots with the same chemical compositions as those three layers have been prepared to evaluate the grain size distribution,microstructure and mechanical properties.The effects of Cu and Ni segregation on the microstructures of those three layers have been explored by thermodynamic calculation.Based on the microstructure and mechanical properties results,an intensive understanding of the cracking in the segregation zone was therefore reached.展开更多
文摘In order to automatically detect the corrosion on the piston rod of hydraulic hoist of hydropower station and find the location of corrosion conveniently and accurately,a piston rod defect detection robot based on machine vision was developed.Firstly,the structure of the robot is presented,the detection system introduces the data collection process in the process of image processing,using a laser camera to capture image information.After the image preprocessing,cascade filter and morphological images after operation,the image information of gradient data,the depth of the defect data is extracted.To acquire the information of image defects in concave and convex,after using the RGB color image information acquisition defects the camera,HSV space separation and median filter and morphological processing are used to extracti defects in the image color information.Finally for defect information coding for quad,through comprehensive information for defect recognition and using QT development the human-computer interaction interface is developed,which can realize the reality and statistics of the robot′s motion control and defect information.Through the experimental verification of the robot′s performance,it is proved that the reliability of the robot′s motion and the accuracy of defect identification meet the design goal.
基金financially sponsored by National Natural Science Foundation of China(Grant No.51201160)Youth Innovation Promotion Association of Chinese Academy of Sciences(2017233)Science and Technology Innovation Foundation from Institute of Metal Research,Chinese Academy of Sciences(Grant No.2015-ZD04)
文摘The segregation of Cu and Ni in a 17-4PH stainless steel piston rod has been confirmed to be responsible for the cracking after heat treatment.Further investigation showed that the segregation zone was composed of three layers,namely the fine grain martensitic layer,the coarse grain martensitic layer and the coarse grain austenitic layer from the matrix to the crack surface.Three button ingots with the same chemical compositions as those three layers have been prepared to evaluate the grain size distribution,microstructure and mechanical properties.The effects of Cu and Ni segregation on the microstructures of those three layers have been explored by thermodynamic calculation.Based on the microstructure and mechanical properties results,an intensive understanding of the cracking in the segregation zone was therefore reached.
