hardness survey

[lahane1443]

i have welded three different test copon for PQR .All of them were weleded by GTAW process.
The thickness of three coupons are 6 mm,9mm,12mm ,all are LTCS Plate material having P1G1 & P1G2 combination. Customer spec asks for macro hardness survey in HV10 as per E92 with three reading in each i.e. PM,HAZ & WELD at top, middle & bottom.

Now the test lab is of opinion that macro hardness with three readings is not possible in HAZ sections for above three samples as the HAZ section is very thin for such a low thickness.

What should i do?
shall i go for micro hardness survey in HV0.5 at all location. can this be acceptable against macro hardness??

 

[metengr]

Yes, microhardness testing is the appropiate method for weld procedure qualification.

 

[TVP]

I agree with metengr, microhardness at HV0.5 should be ok for all regions, although it should be easy to perform HV10 on the PM and weld and compare with HV0.5 measurements.

FYI, ASTM E92 has been canceled and replaced by ASTM E384.