The chemical composition of the fractured blade was analyzed by emission spectrometry. The results showed in Table 1. The results showed that the blade material was consistent with the analysis results of DC51D+Z steel, and it was a commonly steel used to make centrifugal fan blade.
Based on ISO 6892-1:2009, MOD standard, the tensile test was carried out with MTS-809 test machine at room temperature and loading speed of 1 mm/min. Dimensions of tensile test specimens were illustrated in Fig.1. The average yield stress\(\ (\ \sigma_{s})\), ultimate strength\(\ (\ \sigma_{b})\)and elastic modulus\(\ (\ E\ )\) of the three testing samples were listed in Table 2.