DE102005015186A1 - Manufacture of composite automobile component castings including pistons, casts in two stages between which cores are exchanged - Google Patents

Abstract

Casting is carried out in two stages, in a casting unit or mold. In the first stage, an insert is cast using a first material. One or more cores used during this stage are removed, while the insert cools. New cores (5, 6), differing in geometry from the first, are inserted into the mold. In the second stage the composite casting is completed by introducing the second material. The first material is aluminum especially. Exchange of the cores forms a cavity into which magnesium, titanium or another aluminum alloy is introduced. Metallic interdiffusion takes place at the boundary zone between metals, during setting. In addition, interlocking connections (7) enhance mechanical bonding between the metals.

Description

The The invention relates to a method for producing a metallic Composite casting components, in particular for pistons of an internal combustion engine and reciprocating compressor, for gearbox and other housings and for Cylinder heads, the made of an aluminum-magnesium composite, an aluminum-titanium composite or an aluminum-aluminum composite are provided with different alloys, is provided.

From the prior art, a variety of methods for the production of composite metal casting components are known. In the DE 101 12 132 A1 An aluminum-magnesium composite crankcase for an internal combustion engine is described, which is formed of a composite casting, wherein the aluminum component is produced in a first aluminum mold and then machined. This component is then placed in a second die and then cast in this form with magnesium. The presentation of this insert component in a separate casting process with its own first mold is time-consuming and causes considerable production costs. Also, the processing of the insert member, which is necessary so that the second diecasting mold is not damaged, causes additional investment and additional manufacturing costs.

Therefore the object of the invention is the production process of metallic composite cast components, in particular components of a Aluminum-magnesium composite, an aluminum-titanium composite or a Aluminum-aluminum composite with different cast alloys to do so that the manufacturing process for This resulting components is significantly simplified and simultaneously the manufacturing and investment costs are reduced.

Is solved this task in that the manufacturing process of the composite casting component at least in a two-stage casting process in a pouring device so executed is that in a first process step, a first material in the pouring device is introduced and then in a second process step the Composite casting is finished by casting by replacing one or more several cores of the casting from the first process step during the cooling of the first material Cores with a changed geometry in the casting device be used before, in the second step by pour in of the second material of the casting process is completed.

Advantageous is provided that as the first material aluminum in the casting device is poured in and after the replacement of one or more cores in the cavities formed with these cores, the second material magnesium, Titan or another aluminum alloy is filled, and that during the Solidification process of the two materials in addition to the resulting diffusion processes in the Material limit area positive locking Connection areas are provided to increase the material connections.

Prefers It is envisaged that in the highly stressed areas of the composite cast component in the mold the first material that is aluminum introduced and in the lower claimed areas of the second material, wherein in aluminum-aluminum composite castings the alloys of both aluminum materials are different.

A advantageous embodiment is seen in the fact that the exchangeable cores are made of steel.

Essential is due to the new process for producing a composite cast component, that with this very simplified and inexpensive process a metallic Reliable composite cast component arises, that is very good to one Mass production of lightweight pistons for Internal combustion engines is suitable because of these lightweight pistons e.g. the piston crown area and the hub area of aluminum and the piston skirt area and parts of the piston crown are made of magnesium becomes. Due to the composite structure of aluminum and magnesium, the Weight of the piston can be significantly reduced. The method is suitable also for the production of aluminum-magnesium composite housings, e.g. for oil pumps, for transmission or for the production of composite cylinder heads using e.g. Base plate, combustion chambers and coolant areas made of aluminum and the oil-bearing and housing areas be formed from magnesium.

The The invention is described below with reference to a schematic in drawings illustrated embodiment explained in more detail.

It demonstrate:

1 an embodiment of a casting device in section during the first process step;

2 an embodiment of a casting device in section during the second process step;

3 a piston of an internal combustion engine as an embodiment of a composite cast component in perspective view.

The method for producing the metal composite casting provides that both casting methods, eg for the materials aluminum and magnesium in a casting device 1 be performed. This is how the pouring device works 1 corresponding 1 in a first step, a Eingussteil 2 Made of a first material, aluminum, and while the aluminum component cools down, become steel cores 3 and 4 against new cores 5 and 6 according to 2 exchanged and in the hollows formed with these cores of a second material, for example magnesium, titanium or an aluminum alloy is filled, wherein the first cast piece of the composite casting remains in the casting device. Since the first cast piece of the composite casting still has a high temperature, take place in the solidification process, for example, between the aluminum and magnesium boundary areas intensive diffusion processes that lead to the construction of a connection zone. The networking of both material areas is achieved by positive connection areas 7 according to 2 and 3 increased, so that a resilient composite cast component is formed in which, for example, in highly stressed areas of aluminum and magnesium in less stressed areas is arranged or different aluminum alloys are used depending on the component requirement.

In the 3 illustrated embodiment of the pouring device 1 shows a lightweight piston of an internal combustion engine as alunimium magnesium composite casting.

1

mold

2

cast-

3

core

4

core

5

core

6

core

7

positive connection area

Claims (5)

Method for producing a composite metal casting component, in particular for pistons for internal combustion engines and piston compressors, for gearbox housings and other housings and for cylinder heads, which consist of an aluminum-magnesium composite, an aluminum-titanium composite or an aluminum-aluminum composite with different Alloys exist, is provided, characterized in that the manufacturing process of the composite cast component in an at least two-stage casting process in a casting device ( 1 ) is carried out so that in a first process step, a casting ( 2 ) of a first material in the casting device ( 1 ) is produced by casting and then in a second process step, the composite casting is finished cast by replacing one or more cores ( 3 . 4 ) from the first process step during the cooling of the first material cores ( 5 . 6 ) with changed geometry in the pouring device ( 1 ) are used before the casting process is completed in the second process step by pouring the second material. A method according to claim 1, characterized in that as the first material in particular aluminum in the pouring device ( 1 ) and after replacement of one or more cores ( 3 . 4 ) with the new cores ( 5 . 6 formed cavities of the second material magnesium, titanium or another aluminum alloy is introduced, and that during the solidification process of the two materials in addition to the resulting diffusion processes in the material boundary region positive connection areas ( 7 ) are provided to increase the material connections. A method according to claim 1 and 2, characterized in that in the highly stressed areas of the composite casting in the pouring device ( 1 ) the first material, the aluminum is introduced and in the less stressed areas of the composite casting of the second material. Method according to Claims 1 to 3, characterized that in aluminum-aluminum composite castings the alloys the two aluminum materials are different. Method according to one of claims 1 to 4, characterized in that the cores ( 3 - 6 ) are made in particular of steel.