Mechanical Behavior of a Dissimilar Metal Weld Used for Nuclear Power Plants

Abstract:

The mechanical behaviors of dissimilar metal weld SA508-52M-316L in several environments were investigated by using tensile tests with smooth specimens, focusing on the behavior of SA508-52M weld part during slow strain rates testing (SSRT) at 290°C in nitrogen gas and in simulated primary water at different electrode potentials. The mechanical properties at room temperature of main materials were obtained first. When tested at 290°C, the weld exhibited characteristics of dynamic strain ageing (DSA), which was more significant when strain rate was decreased from 1x10^-6 (1/s) to 3.1 x10^-7 (1/s). When tested in the water at the potentials from-720 to +200mV(SHE) , SA508-52M specimens showed the mechanical behaviors almost the same as that in nitrogen gas, with ductile failure happened in the 52M bulk weld metal. When the potential was raised to +300 and +400mV(SHE), brittle failure of stress corrosion cracking (SCC) took place around the interface, causing the significant drop of elongation and reduction in area.

• Periodical: Applied Mechanics and Materials (Volumes 675-677)
• Pages: 47-51
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.675-677.47
• Online since: October 2014
• Authors: Guang Fu Li*, Guan Jun Li, Jun Peng, Mao Long Zhang, Zhi Yuan Sun
• Keywords: Dissimilar Metal Weld, Dynamic Strain Ageing, Mechanical Behavior, Nuclear Power Plant, Primary Water

References

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