Stainless Steel Determination


Our company has stablished that the product contact material must be the stainless steel, but the most our equipments don’t have any certification of material, so I want to know if there is a non-destructive method to check if a material is made of stainless steel 316L or 304

thanks a lot,


Positive Material Identification (PMI) is the identification and analysis of various metal alloys by their chemical composition through nondestructive methods.
These are done
when working with a part that is part of an assembly or that is too large for shipping,
when a sample cannot be cut for routine testing,
when a mixed lot is suspected,
when material identification/documentation has been misplaced.

There are portable x-ray fluorescence (XRF) analysers for this.

I have used a hand-held analyser; you merely point it towards the surface that needs analysis. The technique is non-destructive. The data can be exported into a spreadsheet and you can generate individual reports. You basically get an alloy composition, which the software then determines the grade of stainless steel. The equipment needs calibration and comes with certain metal/alloy standards.

Niton makes a handheld portable analyzer that can be used for this, but there is some serious training as it is a radioactive source.