TECHNICAL FIELD

The subject of the invention is a method for manufacture of hybrid castings which are combined castings connected in a movable fashion, made from metal alloys in sand or permanent moulds.

BACKGROUND ART

From the Polish Prior art, Pat.231589, there is a known method for manufacture of light metal alloy castings zone-reinforced with metal cast-in pieces, especially in sand and permanent moulds where the cast-in pieces are set on stem or perforated chaplets with the head depending on the shape of the cast-in piece after preparing the external surfaces of the cast-in piece beforehand in a known way, comprising setting the casting-reinforcing cast-in metal pieces in the casting in a sand or permanent mould on the parting surface using additional cores where cast-in piece extensions are moulded in locating the cast-in piece in the mould at a distance not shorter than 3 mm from both the internal and the external surfaces and subsequent heating of the cast-in piece in the casting to 600°C additionally increasing the adhesion of the cast-in piece surface as well as safety by removing moisture from the cast-in piece surface, and filling the mould with a light metal alloy, at the above cast-in piece temperature. The casting-reinforcing metal pieces called cast-in pieces are in the form of a rigid rod, wire and/or flexible cable.

From the European patent application EP 32741 14T3, there is a known method reference for manufacture of zone-reinforced light alloy castings. It is a method for manufacture of light alloy castings zone-reinforced with metal cast-in pieces, manufactured especially in sand and permanent moulds, wherein the cast-in pieces are set in the moulds at a distance not shorter than 3 mm from both the internal and the external surface of the casting on stem and/or perforated chaplets depending on the shape of the cast-in piece after preparing the external surfaces of the cast-in piece, they are pre-heated to a temperature of max. 600°C to increase the adhesion of the cast-in piece surface and the moulds are filled with a light alloy, comprising setting the light-metal-alloy-casting reinforcing metal cast-in pieces on the parting surface of the mould using additional cores where cast-in extensions are moulded in for stable setting and aligning the cast-in piece in the mould, wherein the extensions are cut off and removed after casting.

The above solution allows for improving the strength parameters and the safety level while maintaining better parameters without increasing the weight and volume of the final product.

Patent description of invention DE 102009048709A1 presents a metal composite with the area of connection, wherein the composite connection is made by casting and thus creating a permanent joint.

From the international patent application WO 2005042188A1 , there is a known an invention comprising a hybrid component for light structural use which includes a steel piece of high strength and a cast coupling component which is connected by casting with the steel piece permanently and in a rigid manner. Prior art method for forming a hybrid component for light structural use comprises: forming a steel piece formed from high-strength steel into a specific configuration and casting the coupling component on an area of the steel component.

Patent description of invention EP 1673189B1 comprises a hybrid component for use in a light structure, a steel piece formed from high-strength steel, and a coupling component which is cast in this area of the steel piece by local casting of aluminum slurry around the area of the steel piece, thanks to which the coupling component is firmly attached to the steel piece where the steel piece is a tube component.

From the patent application US 9073403B, there is a known comprising a cast hybrid twist beam axle assembly consisting of a steel twist beam and a cast trailing arm for the twist beam which is rigidly connected to the twist beam.

AIM OF THE INVENTION

The aim of the invention is to design and develop a new method of manufacture of hybrid castings which are combined, from metal alloys with a movable connection. The technology of their manufacture consists in manufacture of a hybrid product, i.e., an aluminum alloy casting in connection with another product in the form of a piece made of a steel material, cast iron material, aluminum material, so called cast-in piece which, at the end of the manufacturing process, is characterized by a closed movable connection.

Owing to that specific manufacturing method, it is possible to make items which could already be made, but by additionally incorporating a welding process. The elimination of the additional process allows for achieving homogeneous casting material, avoidance of hot spots which could cause lower strength properties. A high-quality, high-functionality hybrid assembly of pieces connected in a movable fashion produced using that manufacturing method is a product of the combination of casting using different materials and, thanks to combining them, it is possible to make completely new casting designs and products connected in a movable fashion with improved functional properties and quality. The new manufacturing technology also results in lowering manufacturing costs of structural components of this type with new functional properties.

SPECIFICATION

The method for manufacture of hybrid castings especially with movable connections in sand or permanent moulds consists in preparing a metal casting piece for setting in the cope or drag, pre-heating to a temperature depending on the material used to increase the adhesion of the cast-in piece surface in casting a hybrid casting, characterized in that applying a separating agent on a piece in the form of a cast-in piece prepared beforehand and/or core surface and/or cope or drag surface if there is not a core present, preferably a ceramic material, in the area of achieving the movable hybrid casting connection, on the entire surface of the movable hybrid casting connection to a thickness from 1 mm to 5 mm, then setting the cast-in piece in the casting tooling (e.g., pattern) or in a core made of core sand, then filling the cope and the drag with moulding sand, firmly setting and aligning the cast-in piece and/or the core with the cast-in piece in the specially designed cavity in the cope and/or drag, then aligning the cope and the drag using locating points and creating a complete mould, then filling the complete mould with a liquid casting alloy through the sprue, then waiting for the casting to solidify, then knocking out the complete casting with the cast-in piece, removing any instances of flash, removing the separating agent from between the cast-in piece and the casting and obtaining the final hybrid product of combined pieces connected in a movable fashion as a part assembly for use or further processing.

Preferably, the cast-in piece in the movable connection shall be made of the same material as the casting or another steel material, or cast iron, or cast steel.

Preferably, the separating agent in the movable connection between the casting and the cast-in piece is a ceramic material in liquid, solid or foam form.

Preferably, in the movable hybrid connection between the casting and the casting piece, the separating agent in the form of a ceramic material is removed mechanically. Preferably, in the movable hybrid connection between the casting and the casting piece, the separating agent in the form of a ceramic material is removed by immersion in a medium in an ultrasonic cleaner or by high-frequency vibrations.

Preferably, the separating agent, ceramic mass is with the addition of lubricating elements or in the form of bearing alloy.

Preferably, the separating agent in the form of ceramic material separating the two materials in the pouring process has a thermal resistance of minimum 400°C. Preferably, thermal resistance of the ceramic material depends on the cast-in piece material and the casting alloy for the casting.

Preferably, the separating agent in the form of a ceramic material is applied in the movable connection with a brush and/or by spraying.

DETAILED DESCRIPTION

The invention is shown realized as an example in a drawing where Fig. 1 with detail D shows an engineering drawing of a cross-section of the mould layout and the pouring technique for manufacture of the hybrid casting, Fig. 2 shows an engineering drawing of a cross-section plan view of the mould layout and the pouring technique for manufacture of the hybrid casting, Fig. 3 shows an example casting made by following the description of the invention. Example 1

A method for manufacture of hybrid castings especially with movable connections in sand or permanent moulds where a metal cast-in piece 5 for setting in the cope or drag 1 ,2 is heated up to a temperature of 60°C to increase the adhesion of the cast-in piece 5 surface in casting the hybrid casting 4 comprises applying a separating agent which is a ceramic material 6 of a thermal resistance of minimum 700°C with a brush in the area of achieving the movable connection of the hybrid casting, on the entire surface of the movable connection on the alloy steel cast-in piece 5 prepared beforehand, to a thickness of 1.0 mm, then preparing the cope and drag 1 , 2 and setting the cast-in piece in the tooling on the cope pattern for the cope 1 , filling the cope and drag 1 ,2 with moulding sand, then aligning the surfaces 8 using locating points and closing in a known way and filling with liquid aluminum alloy through the sprue 7, and, after solidification of the casting 4 in the mould 1 ,2, knocking out the complete casting 4 with the cast-in piece 5 in a known way, removing any instances of flash, removing the separating agent in the form of ceramic material 6 from between the cast-in piece 5 and the casting 4 by mounting in a fixture prepared beforehand and by using vibrations until the ceramic material 6 crumbles and rotational movement of the cast-in piece on the casting 4 is achieved. The final, hybrid product of combined movable components, as an assembly of the cast-in piece 5 and the casting 4 is ready for direct use or further processing.

Example 2

A method for manufacture of hybrid castings especially with movable connections in sand or permanent moulds where a metal cast-in piece 5 for setting in the cope or drag 1 ,2 is heated up to a temperature of 60°C to increase the adhesion of the castin piece 5 surface in casting the hybrid casting 4 comprises applying a separating agent which is a ceramic material 6 of a thermal resistance of minimum 700°C by spraying in the area of achieving the movable connection of the hybrid casting, on the entire surface of the movable connection on the alloy steel cast-in piece 5 prepared beforehand, to a thickness of 3 mm, then preparing the cope and drag 1 ,2 and setting and aligning the cast-in piece on the cope pattern in the cope half of the mould, then aligning the surfaces 8 of the mould 1 ,2 halves using locating points, then closing the mould, then filling with liquid aluminum alloy through the sprue 7, and, after solidification of the casting 4 in the mould 1 ,2, knocking out the complete casting 4 with the cast-in piece 5 in a known way, removing any instances of flash, removing the separating agent in the form of ceramic material 6 from between the cast-in piece 5 and the casting 4 by mounting in a fixture prepared beforehand in an ultrasonic cleaner where, as a result of ultrasounds, the ceramic material 6 crumbles and separates from the casting 4 and the final, hybrid product of combined movable components is obtained, as an assembly of the cast-in piece 5 and the casting 4, ready for direct use or further processing.