The differences between a 316L and a 316 straight grade are two-fold both in chemistry and mechanical properties. The L grade has a lower maximum carbon limit and the straight grade has increased mechanical properties. If material is certified as straight grade, the carbon content would have to be at a level of 0.030% maximum in order to be dual certified as 316L/316 grade. (presumably the mechanicals would have already been met). If the material is certified as 316L that implies the carbon is a t a maximum level of 0.030% and this can only be certified to the straight grade if the increased mechanicals are met. Below is a summary comparing the two grades for both the flat and bar product.
|SpecificationASTM||Grade||Carbon% max||TensileKsi min||YieldKsi min||Elongation% min||Reduction of Area% min|
If carbon is at or below 0.030% and tensile is at 75KSI min (and yield is at 30 min), the grade becomes dual certified.