Effect of GTA-ultrasonic excitated-voltage on microstructure and impact toughness of CLAMs weldments
1.School of Material Science and Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2.Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031, China)
Abstract： The GTA-ultrasonic, which was stimulated by modulation of ultrasonic excitation to the gas tungsten arc welding（GTAW) source power, was used to weld China Low Activation Martensitic steel（CLAMs) by coupling interaction between arc and workpiece. According to previous experiences, welding current, proper excitated voltage and their combination were selected. The experimental results,comparison analysis show that the microstructure and the mechanical properties of CLAMs weld are ame-liorated remarkably by GTA-ultrasonic. By appropriate combination of GTA-ultrasonic parameters, martensite laths bundle of joints become dense with fine distribution of precipitated carbides. The impact toughness of weld joint is improved markedly with maximum of 80%. Under the combined effect of ar-cultrasonic and heat input, the impact toughness of weld joint increase a trend first and then decrease with the increasing of excitatedvoltage. By controlling the quantity of welding heat input, high impact toughness can be achieved by appropriate enhancement of excitated-voltage.
2011, Vol. 32 
