A Monitoring System for Crack Growth Rate Based on Direct Current Potential Drop

Monitoring systems of stress corrosion crack (SCC) growth rate of nuclear power structure materials has had many problems like monitoring difficulties and cost, etc. Taking into account these problems, a monitoring system for stress corrosion crack (SCC) growth rate based on direct current potential drop (DCPD) technology has been developed. The principle and details of the DCPD in monitoring the materials crack growth are introduced. The calibration relationship between the potential drop and the crack growth length is obtained by numerical simulation. The Crack growth length can be obtained by the real-time monitoring of potential data. As per demand, the system can communicate successfully with the instrument, and realize the functions of instruments like parameter setting, data acquisition and processing of the instrument parameters in the monitoring. The potential of the standard Crack Tip(CT) sample has been tested using this system. The results show that every function runs successfully, the characteristics of the monitored potential signal are consistent with theoretical expectations, and can meet the monitoring requirements of the potential drop signal effectively.