Behov av avspänningsglödgning efter svetsning av varmhållfast stål typ 1 Cr 0.5 Mo

Stressrelief heat treatment of heat resistant steels is always done in large wall thickness but is sometimes оmitted for thin materials such as boiler tubes. Tubes has been tested in an experimental boiler without any postheat treatment with good results.

Test welds of heavier goods of 1 % Cr 0.5 % Mo has been tested in plate (15 mm) and tube (12 - 30 mm). Vickers hardness tests show very acceptable results and the Charpy-V-impact tests show a decrease in HAZ but the decrease is acceptable.

Tests have also been done with tube material in a weld simulator, but the correlation to arc-welded structures were not acceptable for fracture mechanic approach