How does the low temperature affect the toughness of structural steel welds made using different welding processes?
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Low temperature has a significant impact on the toughness of structural steel welds made using different welding processes. In the case of X80 girth-welded steel pipelines, the use of ultra-low heat input during welding increases the fracture toughness of the coarse-grain heat-affected zones (CGHAZs) and improves their deformation capacity . On the other hand, high heat inputs in high-efficiency submerged arc welding wires for bridges lead to a decrease in impact toughness due to the coarsening of the microstructure and the presence of inclusions . In heavy-wall X80 weld joints, the influence of intercritically reheated coarse-grained HAZ (ICCGHAZ) on the overall toughness depends on the temperature, with embrittlement occurring at temperatures below -45 °C . The toughness of low-temperature phase transformation (LTPT) weld metals is affected by the presence of oxide inclusions, which can be reduced by using pure inert shielding gases . Laser welding of DP800 and DP1000 steels results in fully martensitic fusion zones and a decrease in strain hardening capacity at low temperatures .
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| The provided paper does not directly address the effect of low temperature on the toughness of structural steel welds made using different welding processes. |
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