High-temperature sintering can be a key to increase the material strength of powder metal components. The dimensional change due to high-temperature sintering can lower the precision of PM parts, therefore press and sinter processes could be less cost effective. The aim of this work is to evaluate the loss of dimensional and geometrical precision of the components in comparison with the material strength improvements. Two mechanical parts made of chromium steel were sintered at different temperatures. The porosity evolution was investigated by image analysis. The mechanical properties were estimated by the computation of the fraction of load bearing section. Both the dimensional and the geometrical precision were calculated by implementing a specific procedure with a coordinate measuring machine. The results show a significant improvement of porosity increasing the sintering temperature and so does the fraction of load bearing section. Increasing the sintering temperature the dimensional change increases as well, while the geometrical characteristics and the dimensional precision remain within the same tolerances.
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