Material Testing Results Lab Comparrison
Material Testing Results Lab Comparrison
(OP)
How close should the mechanical and chemicals be when I have tested the same heat number/heat lot number at different labs? (Within 1% of each other)
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Material Testing Results Lab Comparrison
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RE: Material Testing Results Lab Comparrison
For ultimate tensile strength measured on a standard specimen using a universal testing machine, I would expect the mean of multiple samples from each lab to be within 5% of each other. One percent would be nice, but not likely. For example, if the tensile strength is 500 MPa, I don't see two labs reporting values within 5 MPa.
For chemical composition of a steel alloy measured by an emission spectrometer, I would expect the composition's to be within 1% of each other (e.g. steel with 0.500 mass percent Mo should be 0.500% at lab 1 and 0.505% at lab 2).
Regards,
Cory
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RE: Material Testing Results Lab Comparrison
RE: Material Testing Results Lab Comparrison
RE: Material Testing Results Lab Comparrison
After analysing a sample,please resubmit the same sample to them for confirmation and the values will not be the same. Especially in C,S and P. The lab technician refuse to accept these variations and insists that his readings are precise.!!
In mechanical testing there will be a variation in YS and elongation or in impact testing always controversial to say the least.
Hence the need for statistical analysis to arrive at the right inferences.