Methods and systems for die casting
Methods and systems for high pressure die casting with metal alloys of low silicon content are described. Metal alloys can be modified with nanoparticles to achieve high fluidity and hot cracking resistance to be compatible with high pressure die casting. The die cast metal parts have high strength, high ductility, and high thermal and electrical conductivity. The die cast metal parts can be anodized with different colors.
1 . A method for die casting comprising:
melting a metal alloy, wherein the metal alloy is modified with at least one type of nanoparticle, wherein the metal alloy comprises a silicon weight concentration of less than 4.0%;
filling a die with the molten metal alloy under a pressure greater than 100 MPa; and
cooling the die to solidify the molten metal alloy with a cooling rate between 100° C./s and 300° C./s.
2 . The method of claim 1 , further comprising anodizing the die cast metal alloy with at least one color.
3 . The method of claim 1 , wherein the metal alloy is selected from the group consisting of an aluminum alloy, a magnesium alloy, a copper alloy, and a zinc alloy.
4 . The method of claim 1 , wherein the metal alloy is selected from the group consisting of A201, AA2024, A206, AA2618, AA5083, AA6013, AA6061, AA6063, AA6069, AA7034, AA7050, AA7075, and AA7068.
5 . The method of claim 1 , wherein the at least one type of nanoparticle is selected from the group consisting of a metal oxide, a non-metal oxide, a metal carbide, a non-metal carbide, a metal silicide, a metal boride, a metal nitride, and any combinations thereof.
6 . The method of claim 1 , wherein the at least one type of nanoparticle has a structure of a core-shell particle.
7 . The method of claim 1 , wherein the at least one type of nanoparticle comprises less than 30 vol. % of the metal alloy.
8 . The method of claim 1 , wherein the nanoparticle comprises 0.1 vol. % to 2 vol. % of the metal alloy.
9 . The method of claim 1 , wherein the metal alloy comprises AA6061 and the nanoparticle comprises TiC or TiB 2 , and the TIC or TiB 2 nanoparticle comprises 1.0 vol. % of the metal alloy.
10 . The method of claim 1 , wherein the die cast metal alloy as formed has an elongation equal to or less than 30% and an ultimate tensile strength greater than 500 MPa.
11 . The method of claim 1 , wherein the die cast metal alloy has a thickness of at least 0.2 mm.
12 . The method of claim 1 , further comprising a post process selected from the group consisting of: a T5 treatment, a natural aging treatment, and a T6 treatment.