**Acknowledgements**

contact forces or stresses are very small at this region, the debonding occurs. While with the further increase of the compaction pressure, the bulk density of the compact increases. The normal contact forces or stresses at the debonding region increase due to the extrusion from neighboring particles, leading to the rebonding at the interface. Through comparison, one can conclude that the occurrence of debonding phenomenon, which has also been identified in others' work [49], is mainly caused by sufficient tangential forces but insufficient normal forces at the interface. Therefore, the interface should have a certain shear strength and relatively large normal strength, which can not only effectively avoid the possible debonding, but

DEM-FEM coupled MPFEM modeling on the single action die compaction of Al/SiC core/ shell (core: SiC; shell: Al) composite powders with different initial packing structures was conducted from particulate scale in 2D. The effects of compaction pressure, initial packing structure, and SiC content (composition) on the packing densification were systematically presented. Various macro and micro properties such as relative density and distribution, stress and distribution, particle rearrangement through translational motion and rotational motion, deformation and mass transfer, and interfacial behavior between composite particles

**1.** MPFEM simulation can effectively reproduce the compaction densification of Al/SiC com-

**2.** Beyond a certain Al content, the compaction on both ordered and random initial packings of the composite particles all can realize the full densification, however, the micro properties in these compacts are initial structure sensitive. And the densification rate is also

**3.** The compaction on Al/SiC core/shell composite powders can obtain more uniform relative

**4.** During compaction on random initial packings of Al/SiC composite powders, obvious particle rotations can be observed with the relative density of the compact between 0.74–0.82, and the value of average rotational angles is also affected by the initial packing structure.

**5.** The debonding between SiC core and Al shell during compaction on random initial packings mainly occurs at the area close to the large pore, where the normal stress is small and the shear stress is relatively large. To avoid it, sufficient normal stress at the core/shell contact area should be satisfied. For the compaction on ordered initial packing such as SC and HCP structures, debonding mainly appears close to the punches when the SiC content

The researches can not only enhance people's understanding on the compaction densification of Al/SiC composite powders with core/shell structures and various initial packing states, but

is relatively high, and it will be disappeared in the final stage of compaction.

also make the distribution of equivalent strain in the matrix more uniform.

were characterized and analyzed. Following conclusions can be drawn:

posite particles with core (SiC)/shell (Al) structures from particulate scale.

density and stress distributions than other Al/SiC composite systems.

**4. Conclusions**

36 Powder Technology

different.

The authors are grateful to National Natural Science Foundation of China (No. 51374070) and Fundamental Research Funds for the Central Universities of China (No. N162505001) for the financial support of current work.
