A plurality of inlet-side octagonal cells and outlet-side quadrangular cells partitioned by partition walls on an upper surface and a lower surface are opened in a green honeycomb molded body in which a plurality of through-holes partitioned from each other by the partition walls are open in an end surface of a columnar body. Four outlet-side quadrangular cells having a smaller opening area adjoin around one inlet-side octagonal cell through the partition walls. The partition walls are joined together and the inlet-side octagonal cells are opened while closing the outlet-side quadrangular cells on the inlet side and the outlet-side quadrangular cells are opened while closing the inlet-side octagonal cells on the outlet side in a particulate-matter-removing filter such as a diesel particulate filter.

A method of forming a composite component includes laying up a plurality of composite plies around a mandrel assembly to form a composite ply core. The mandrel assembly includes a mandrel having an inner structural body and an outer release layer. The mandrel is configured to form a cavity in the composite ply core. The method also includes processing the composite ply core containing the mandrel assembly to compact the plurality of composite plies together. Further, the method includes removing the mandrel assembly from the composite ply core to form the cavity. Further, removing the mandrel assembly from the composite ply core includes melting out the inner structural body and removing the outer release layer after melting out the inner structural body.

The present disclosure relates to a 3D printer for construction for printing and forming various structures, in which agitating blades 45 capable of auto-rotation are mounted inside a nozzle 10 discharging a printing material such as concrete or mortar, to thereby enable agitation of a fluid printing material inside the nozzle 10. According to the present disclosure, agitation of the fluid printing material inside the nozzle 10 of the 3D printer for construction may be facilitated to prevent material segregation and maintain a homogeneously mixed state of materials constituting the fluid printing material.

The present disclosure relates to a 3D printer for construction for printing and forming various structures, in which agitating blades 45 capable of auto-rotation are mounted inside a nozzle 10 discharging a printing material such as concrete or mortar, to thereby enable agitation of a fluid printing material inside the nozzle 10. According to the present disclosure, agitation of the fluid printing material inside the nozzle 10 of the 3D printer for construction may be facilitated to prevent material segregation and maintain a homogeneously mixed state of materials constituting the fluid printing material.