Structure and Mechanical Properties of Welded Joints for Nuclear Power Plants of Type MIR 1200

Abstract

The paper deals with research, development and verification of production technology of selected welded joints for pressure vessels of primary circuits of nuclear power plants of type MIR 1200. Effect of various welding technology including simulation heat treatment on mechanical and fracture properties have been studied. Four type of homogenous 10GN2MFA – 10GN2MFA type of welded joints have been prepared for experimental programme. Conventional mechanical properties (tensile and impact test) as well as unconventional mechanical properties (fracture mechanics, low-cycle fatigue and stress corrosion cracking in water environment) have been studied. Effect of elevated working temperature on structure and material properties has been evaluated. Temperature dependencies of shear fracture have been plotted and effect of welding procedure on transition temperature shift has been evaluated. Experimental data have been compared with numerical simulation using FEM.

Structure and Mechanical Properties of Welded Joints for Nuclear Power Plants of Type MIR 1200

“…Mechanical properties including transition temperature of all welds under investigation were satisfactory and meet requirements in the Table 2. In fact real level of mechanical properties was found to be much higher compare to the requirements [1].…”

Complex Evaluation of Structure and Material Properties of Selected Welding Joints

“…The highest initial value of fracture resistance (corresponds to the value of the J-integral at the place of stable crack growth of 0.2 mm) was measured in weld 3 (welded by SMAW technology) in comparison with other welds produced by SAW method, see Table 3. However, it must be stated that the initial values of the J-integral are very high for all monitored welds and indicate a high toughness of the studied materials [3,4].…”