Susceptibility of Steel to HI-SCC

A more recent test (DlB-test) utilises a solution containing 5 g/1 804, 0.5 g/1 of CT and lg/1 of SCN (added as potassium salt). This test has the advantage that the test solution is less aggressive and the amount of hydrogen that is developed during the test is comparable with that produced in practice on the surface of prestressing tendons within the ducts in defective conditions. The time to fracture required is 2000 h. All types of steel that caused damage in field, failed in this DIB standard test within 2000 h [6]. 

Test Test solution Temperature Load life time required (h) 

FIP 200 g NH4SCN -t 800 g H2O 50°C 80% of tensile strength Cold-drawn wire 2-3 Quenched and tempered wire 10-15 Hot-rolled bar 30-50 

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