Experimental study on mechanical properties of corroded steel used as containment liner in nuclear power plant

Abstract

ABSTRACT The paper presents an experimental study on the tensile mechanical properties of P265GH steel that is used as containment liner in a nuclear power plant. P265GH steel plates were first corroded to eight corrosion levels (up to 50%). Then uniaxial tensile tests were carried out. Finally an empirical model was established to describe the constitutive relationship of corroded P265GH steel. For P265GH steel plates with constant thickness, Young’s modulus was less affected by corrosion, while yielding strength, hardening strain, ultimate strength and its corresponding strain, and ultimate strain decreased when increasing the corrosion degree. The plastic platform shortened and even disappeared when the corrosion rate increased, and the corroded P265GH steel plates became more brittle. The proposed model can be used to describe the constitutive relationship of corroded P265GH steel. For P265GH steel plates with varying thickness, yielding strength, hardening strain, ultimate strength and its corresponding, and ultimate strain decreased with the increases in the corrosion degree. The corroded steel plates were prone to fracture at the location of the welding joints. By comparison with experimental results of P265GH steel plates with constant thickness, the yielding and ultimate strengths decreased more rapidly indicating a big influence from the welding.