Measurement Uncertainty Evaluation on Porosity Rate of Sintered Metal Materials

The uncertainty sources in measurement of porosity rate of sintered metal materials were analyzed, and the uncertainty of the measurement results was evaluated. The results show that the uncertainty sources in measurement of porosity rate of the sintered metal materials mainly come from weighing sample's mass in air, sample's mass in water with water completely be soaked in and sample's mass in air with water completely be soaked in, data rounding and so on. The uncertainty report of measuring porosity rate of a sintered metal rotor bush was as following:K=26.4%,U=0.2%,k=2 (K being the porosity rate, U being the extended uncertainty, and k being the coverage factor).