Failure at base metal during bend test.

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We recently performed a PQR for welding Carbon steel IS2062  with E316L using FCAW. However, during bend tests, both the face bend specimens failed at the base metal (Not at weld or HAZ). Would the still test be considered failed? Where can I find details about this in ASME SEC IX
Reply:I can't answer your question about test and reg. specs, but would be interested in whether an unwelded specimen would give similar results.
Reply:The specimen failed at around 120 deg bend. The lab technician was confident that the problem was with the parent metal.
Reply:First, why weld carbon steel with 316 SS?  if you have to weld CS with SS, 309 is generally the best choice since it's alloy content allows the weld mixture with CS to remain Austenitic, non-hardenable and ductile.  On the other hand, with moderate diliution of CS, the 316 SS weld could form hard and brittle Martensite.It failed in the base metal, outside the heat affected zone?  That would be very strangeI don't know the carbon/alloy content and hardenabilty of the that steel, but I would guess the failure would be one of three types:1.  In the HAZ due to some combination of hardening, excessive grain growth, and embrittlement that is related to the base metal cabon/alloy content (carbon equivalent) and possibly excess heat input, or need for preheat/postheat.2.  In the fusion zone, due to simple cold lap/lack of fusion.3.  In the weld metal due to dilution of 316 SS with CS and the formation of martensite and a hard brittle weld.Some things that would help diagnose the cause of failure:The specified composition of the steel and a calculated carbon equivalent to see how hardenable the steel is.A photograph of the failure to see the exact location of the failure.A macro etched cross section of the weld in the failure area to see the size of the HAZ and degree of grain coarsening.A micro-hardness traverse across the weld cross section to see the hardness changes from base metal to HAZ to weld.
Reply:QW-202.  If determined that the cause of failure is not related to welding parameters, another test coupon may be welded using identical welding parameters.  If there is enough of the original test coupon remaining, additional test specimens may be removed as close as practicable to the original specimen to replace the failed test specimen.  Outside of that, no fudge factor.
Reply:I will try to obtain pictures of the specimen. The failure occured in the CS portion. We were told to re-qualify with s235jrg2 instead of IS2062. I was however hoping to find some clause maybe  that would exempt fracture in the base metal and still consider the test as passed.
Reply:Couldnt get pictures since cameras are not allowed inside the factory. Anyways we are going for the retest since everybody that I have consulted has said this is not acceptable. Thanks for the reply all.
Reply:is the direction of rolling perhaps the problem? ive seen them break for no good reason and we concluded that the bevel was cut with the grain.only thing worse than an ugly woman is an ugly weld