Crack initiation and propagation resistance of hsla steel welded joint constituents

The welded joint is heterogeneous in its microstructure, mechanical and geometrical properties, thus the stress field is affected by different factors as well as by residual stress. Therefore, special procedures are needed for experimentally determining the fracture toughness in plane strain, K-Ic, and the impact toughness, usually associated with difficulties in interpreting the measured values. Notched specimens are tested by instrumented Charpy in order to determine impact energy and crack initiation and propagation energies. The pre-cracked specimens are tested by standard, using three-point bending specimens, as geometrically closest to Charpy specimens. In both cases, the notch and crack are located in all various regions of the welded joint of the high-strength low alloyed steel NIONIKRAL-70. Analysis of the results includes speculations on the ratio of energies for crack initiation and propagation vs. fracture toughness

Crack initiation and propagation resistance of hsla steel welded joint constituents

The welded joint is heterogeneous in its microstructure, mechanical and geometrical properties, thus the stress field is affected by different factors as well as by residual stress. Therefore, special procedures are needed for experimentally determining the fracture toughness in plane strain, K-Ic, and the impact toughness, usually associated with difficulties in interpreting the measured values. Notched specimens are tested by instrumented Charpy in order to determine impact energy and crack initiation and propagation energies. The pre-cracked specimens are tested by standard, using three-point bending specimens, as geometrically closest to Charpy specimens. In both cases, the notch and crack are located in all various regions of the welded joint of the high-strength low alloyed steel NIONIKRAL-70. Analysis of the results includes speculations on the ratio of energies for crack initiation and propagation vs. fracture toughness

Temperature and time effects on fracture toughness values in welded joint

Temperature and time effects on fracture toughness have been investigated for characteristic regions in a welded joint made of Cr-Mo steel A-387 Gr. B. Comparative analysis of fracture toughness values for characteristic regions in welded joint has been made for both temperatures (20 ºC and 540 ºC) and for old and new material

Temperature and time effects on fatigue strength of weldments

Temperature and service time effects on A-387 Gr. B Cr-Mo steel weldment fatigue strength have been evaluated. To assess service time effect on fatigue strength, samples are take from 40 years “old” material, whereas temperature effects are followed by comparing fatigue strength of parent metal (PM) and welded joint (WJ) at 200 and 5400 C

Temperature and time effects on fatigue strength of weldments

Temperature and service time effects on A-387 Gr. B Cr-Mo steel weldment fatigue strength have been evaluated. To assess service time effect on fatigue strength, samples are take from 40 years “old” material, whereas temperature effects are followed by comparing fatigue strength of parent metal (PM) and welded joint (WJ) at 200 and 5400 C

Temperature and time effects on fracture toughness values in welded joint

Temperature and time effects on fracture toughness have been investigated for characteristic regions in a welded joint made of Cr-Mo steel A-387 Gr. B. Comparative analysis of fracture toughness values for characteristic regions in welded joint has been made for both temperatures (20 ºC and 540 ºC) and for old and new material