[MW:31440] brittle fracture CS 516 Gr.70N

Dear Fiends,

I have a question about how excessive heat input affects SAW type welding, in a steel SA 516 Gr. 70 N. That is, a material subjected to Charpy test at -45C, and gave brittle fracture with absorbed energy between 4 to 6 lb-ft.

The WPS / PQR clearly rated, but shop production welding gave these results on pressure vessels.

My certainties indicate that coarse-grained ferrite and widmanstatten ferrite could be formed during the cooling of the weld (highly brittle), and not the expected acicular ferrite, which is the appropriate structure for excellent ductile fracture results in this type of steel.

 

I open the forum,

 

Thanks for your attention.

 

Regards,

Ramon Briceno

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