The Research Of The Computer-aided Hydrogen Damage Inspection Technology

In this paper, the mechanism of hydrogen absorption and diffusion in metals and the electrochemical methods for the investigation of metal-hydrogen systems are extensively reviewed. Three different analytical methods for the existing hydrogen permeation model and the inflexion-tangent method are presented and compared, and their applicability and limits of application are also demonstrated. A model for hydrogen permeation through a multi-layered material under ideal conditions is presented. From this model, the hydrogen concentration for both the non-steady permeation and steady permeation in each layer and the lag time can be calculated.With the software kit VtoolsD of the Vireo Software Inc. to develop VxD, the virtual device driver is developed. The VxD take charge of the control and communication of the physical device, the DLL is the interface between the virtual device driver and the application. The application can control the data-collection card through the dll. With the function of Query PerformanceFrequency and QueryPerformanceCounter provided by the Windows operating system, the minimum cycle of time is 0.1 ms.With the software kit Visual C++ 6.0 of the Microsoft Inc., the data collection and analysis program, which consist of the user interface sub-module, the digital filter sub-module, the data save sub-module and the data analysis sub-module, is developed. The user interface sub-module is used to show the real-time curves and the history curves, the digital filter sub-module with the combined filter technique is used to filter the white noise and the pulse noise. The data save sub-module is used to save the collection data to the hard disk. The data analysis sub-module is used to show the hydrogen concentration curve in metal after the analysis of the collection data. The whole data collection and analysis software can be friendly and easily operated.The data collection and analysis software and the data collection card constitute a perfect in-situ, instantaneous and non-destructive hydrogen damage inspection system. From the electrochemical hydrogen permeation experiment, it is proved that the whole inspection system can work correctly and reliably.