Tensile strength variation in the same plate

[goodbadgood]

HI

I have one question for you guys .

I am reviewing the tensile test reports for the plate of SA516 Grade 70. 2 samples have been extracted from the same plate but the values of UTS are different while yeild strength remasn same.

I am getting 474 Mpa and 487 Mpa as UTS in the 2 samples.

Anyone has any idea why there is such variations coming.

Thanks in advance

 

[metengr]

The variation in tensile properties is not that unusual, and in fact within expected tolerance. The tensile properties will always vary in wrought products, such as SA 516 Gr 70 plate from the center section toward the outer surfaces because of normal processing from original casting to forming the wrought end product. The key for SA 516 plate is to make sure the variation or spread does not fall below the minimum specified.

The causes are from regions of chemical segregation to heat treatment limitations that produces variability because of material thickness.