Mould for injection moulding made by additive manufacturing

A method for designing a mould for injection moulding, comprising:

• a) providing a mould body made by additive manufacturing and comprising:
• a plurality of boundary surfaces, said plurality of boundary surfaces comprising at least one moulding surface configured to delimit a mould cavity,
• a functional domain portion on which said plurality of boundary surfaces and said at least one moulding surface are formed, said functional domain portion being composed of a solid, continuous material structure covering a fraction of the mould body,
• an application domain portion which is the complement of the functional domain portion in the mould body, said application domain portion being composed of a three-dimensional material lattice structure comprising an ordered repetition of unit cells including a periodic minimal surface, wherein at least one geometrical parameter of said periodic minimal surface is tuned locally to form unit cells with different densities of material, and
• at least one conformal cooling channel formed into the mould body, and wherein said application domain portion surrounds said at least one conformal cooling channel in such a way that said periodic minimal surface is incorporated inside said at least one conformal cooling channel,
• b) providing a three-dimensional geometrical model of the mould to be designed,
• c) determining the functional domain portion and the application domain portion in the mould body of the mould,
• d) tuning said at least one geometrical parameter of said periodic minimal surface based on a physical model of the mould, and
• e) creating an electronic file storing data indicative of a digital model for constructing the mould by additive manufacturing.