Checking phosphorus levels in an alloy via spectrometer

[Jerry66]

Is phosphorus levels hard to detect by a spectrometer and should the results vary, like from .001 to .003 on the same sample?

 

[TVP]

1. What kind of alloy (steel, stainless steel, cast iron, etc.)?
2. What kind of spectrometer (be specific)?

One thing to keep in mind, P segregates in Fe/steel, so its local composition varies.

 

[Jerry66]

This is in NH41, An aluminum alloy for die casting.

 

[Jerry66]

The spectrometer is a shamadzu

 

[TVP]

I am assuming you mean an Optical Emission Spectrometer such as the PDA-7000 series from Shimadzu. As shown on page 6 of the .pdf file linked below (page 7 of the document), the range of P that can be detected in Al alloys is 0.001 to 0.02% by mass. When extremely small amounts of elements like P are present in Al, it is common to see some variation in the detected concentration at the lower limit. It is a common practice in indurtry to use a threshold of 0.005% by mass when reporting trace elements, meaning anything below 0.005% is reported as "< 0.005%" instead of 0.001 or 0.003, etc.

http://speceng.net/sitebuilderconte...alog20of20optical20emission20spectrometer.pdf

 

[Jerry66]

my spectrometer is a shimadza OES-55OOII,Thanks for yor reply on this you have been very helpful, Thank you.