PSI - Issue 2_B

Su Jie et al. / Procedia Structural Integrity 2 (2016) 2222–2229

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Su Jie et al./ Structural Integrity Procedia 00 (2016) 000 – 000

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Local necking

Fig. 9. Local necking band in matrix containing few dispersion particles

Fig. 10. Separation of the matrix containing abundant particles

After in situ tension, fracture morphology is observed by SEM. Except for the breaking LPs and CSPs, honeycomb like small dimples due to the matrix ductile failure are widely distributed. In addition, some ductile dimples of equivalent size of small particles are also detected at the boundary of CSPs. As noted above, the tensile strength of IPM is very high because no debonding of IPM is observed in the whole in situ SEM test with tensile load. Therefore these small-particle-size ductile dimples on fracture surface may just act as the result of coalescence of MCs, as shown in Fig. 11.