We have an internal process of scanning raw stock material using an XRF (x-ray fluorescence) analyzer (our analyzer is the Hitachi X-MET8000 Optimum). We had a piece of Aluminum Nickel Bronze (AMS 4640H) fail showing the Zinc content at .36%. Per the standard, the Zinc should be between 0-.3%. I then sent a piece of material to a secondary testing lab who showed the Zinc at .41% (using ASTM-E1086/14 MOD--honestly I don't know anything about this standard).
I contacted our vendor who requested a small piece of material for additional testing. They sent the material to 2x different labs.
Lab 1: .26% Zinc using test method ASTM E1621 (again, I know nothing about this spec).
Lab 2: .06% Zinc using specification ASTM E2 SM 5-17 (again, I know nothing about this spec).
The original mill certification shows the Zinc at .07%.
Question 1: Has anyone ever come across this type of discrepancy?
Question 2: Does anyone know if there is something about Aluminum Nickel Bronze that can cause such a wide variance in readings?
Question 3: How would you proceed to try to find the 'cause' and correct the discrepancy given such a wide range of readings?
I contacted our vendor who requested a small piece of material for additional testing. They sent the material to 2x different labs.
Lab 1: .26% Zinc using test method ASTM E1621 (again, I know nothing about this spec).
Lab 2: .06% Zinc using specification ASTM E2 SM 5-17 (again, I know nothing about this spec).
The original mill certification shows the Zinc at .07%.
Question 1: Has anyone ever come across this type of discrepancy?
Question 2: Does anyone know if there is something about Aluminum Nickel Bronze that can cause such a wide variance in readings?
Question 3: How would you proceed to try to find the 'cause' and correct the discrepancy given such a wide range of readings?