We are welding SA-516 Gr70 to 516 Gr70, 8 MM thick plates with single bevels. We have a 8 MM thick deposit of GTAW (ER70S-2) in the root with the balance of bevels filled.
Heat input for the GTAW was 1.85 KJ/MM to 2.35 KJ/MM . The interpass temperature was 130 – 150°C.
The Charpy inpact numbers all fail in the HAZ (values are HAZ 1,2 & 3 – 210,206,214 & Energy Absorbed1,2 & 3 – 8,10,18Joules & Average joules Actual-,12,Required- 12 Minimum),Test Temperature = -49°C ,MDMT = -39°C and two  specimens even failed in the weld on the plate.
The plates were all purchased in the normalized & impact (-46°c) condition with the grain structure perpendicular to the weld.
Anyone care to comment?

Regard's

Varun Kumar