Forming complex-shaped aluminum components
AssigneeAdvanced Materials Technologies Pte. Ltd.
InventorsChee-Tian Yeo, Lye-King Tan
Life of this patent
Estimating the term…
Abstract
Although MIM (metal injection molding) has received widespread application, aluminum has not been widely used for MIM in the prior art because of the tough oxide layer that grows on aluminum particles, thus preventing metal-metal bonding between the particles. The present invention solves this problem by adding a small amount of material that forms a eutectic mixture with aluminum oxide, and therefore aids sintering, to reduce the oxide, thereby allowing intimate contact between aluminum surfaces. The process includes the ability to mold and then sinter the feedstock into the form of compacted items of intricate shapes, small sizes (if needed), and densities of about 95% of bulk.
Claims34
A process to manufacture an aluminum object having a complex shape, comprising:
- providing a first powder of aluminum particles having a first average size;
- providing a second powder of additive particles, known to form a eutectic mixture with aluminum oxide, having a second average size;
- mixing said powders together in a relative concentration by weight and then adding a binder material, thereby forming a feedstock;
- injecting said feedstock into a mold thereby forming a green part;
- releasing said green part from said mold and removing all of said binder, thereby forming a skeleton;
- heating said skeleton at a temperature sufficient to melt said eutectic mixture, thereby facilitating sintering of said aluminum particles to form said object to a density that is at least 95% that of bulk;
- and
- wherein said relative weight concentration of each powder is in inverse proportion to its average particle size.
A process to manufacture an aluminum alloy object having a complex shape, comprising:
- providing a first powder of aluminum alloy particles having a first average size;
- providing a second powder of particles, of a material known to form a eutectic mixture with aluminum oxide, having a second average size;
- mixing said powders together in a relative concentration by weight and then adding a binder, thereby forming a feedstock;
- injecting said feedstock into a mold thereby forming a green part;
- releasing said green part from said mold and removing all of said binder, thereby forming a skeleton;
- heating said skeleton at a temperature sufficient to melt said eutectic mixture, thereby facilitating sintering of said aluminum alloy particles to form said object to a density that is at least 95% that of bulk;
- and
- wherein said relative weight concentration of each powder is in inverse proportion to its average particle size.
A process to manufacture an aluminum object having a complex shape, comprising:
- providing a powder of aluminum particles having a first average size;
- providing a powder of silicon carbide particles having a second average size;
- adding at most 5% by weight of said silicon carbide powder to said aluminum powder, mixing said powders together, and then adding a binder, thereby forming a feedstock;
- injecting said feedstock into a mold thereby forming a green part;
- releasing said green part from said mold and removing all of said binder, thereby forming a skeleton;
- and
- then heating said skeleton for a period of time whereby said silicon carbide particles facilitate sintering of said aluminum particles thereby forming said object to a density that is at least 95% that of bulk.
A process to manufacture an aluminum object having a complex shape, comprising:
- providing a powder of aluminum particles having a first average size;
- providing a powder of metallic fluoride particles having a second average size;
- adding at most 5% by weight of said metallic fluoride powder to said aluminum powder, mixing said powders together, and then adding a binder, thereby forming a feedstock;
- injecting said feedstock into a mold thereby forming a green part;
- releasing said green part from said mold and removing all of said binder, thereby forming a skeleton;
- and
- then heating said skeleton for a period of time whereby said metallic fluoride particles facilitate sintering of said aluminum particles thereby forming said object to a density that is at least 95% that of bulk.
A process to manufacture an aluminum alloy object having a complex shape, comprising:
- providing a powder of aluminum alloy particles;
- providing a powder of silicon carbide particles;
- adding at most 5% by weight of said silicon carbide powder to said aluminum alloy powder, mixing said powders together, and then adding a binder, thereby forming a feedstock,
- injecting said feedstock into a mold thereby forming a green part;
- releasing said green part from said mold and removing all of said binder, thereby forming a skeleton;
- and
- then heating said skeleton for a period of time whereby said silicon carbide particles facilitate sintering of said aluminum alloy particles thereby forming said object to a density that is at least 95% that of bulk.
A process to manufacture an aluminum alloy object having a complex shape, comprising:
- providing a powder of aluminum alloy particles;
- providing a powder of metallic fluoride particles;
- adding at most 5% by weight of said metallic fluoride powder to said aluminum alloy powder, mixing said powders together, and then adding a binder, thereby forming a feedstock;
- injecting said feedstock into a mold thereby forming a green part;
- releasing said green part from said mold and removing all of said binder, thereby forming a skeleton;
- and
- then heating said skeleton for a period of time whereby said metallic fluoride particles facilitate sintering of said aluminum alloy particles thereby forming said object to a density that is at least 95% that of bulk.
Dependencies are inferred from the claim text.