DE1966881A1 - Sliding bearing of ptfe filled with metal - powder and binder - Google Patents

Abstract

Binder, which adheres the running layer and the bearing face which carries it, is at least one thermoplastics such as polytrifluorochloroethylene, polyvinyl fluoride or polyvinylidene fluoride, pref. a thermoplastic copolymer of tetrafluoroethylene and hexafluoropropylene.

Description

PATENT ADVOCATE DIPL-PHYS. HEINRICH SEIDS 62 Wiesbaden-Bierstadt · Bierstadter Höhe 15 · P.O. Box 12068 · Telephone (0 6121) 56 53 82 Postscheck Frankfurt / Main 181008 · Bank Deutsche Bank 3956372 · Nass. Sparkasse 108003065

P 19 66 881.6 Wiesbaden, August 28, 1974

G 326 g / ha

GIyco-Metall-Werk e Daelen & Loos GmbH

¥ iesbaden-Schierstein Eliminated from P 19 32 343.4-12

Process for the production of self-lubricating slide bearing elements

The invention relates to a method for producing self-lubricating sliding bearing elements metallic carrier and a running layer made of a preferably metal powder-containing mixture of polytetrafluoroethylene and a thermoplastic compound as a binder.

In the German patent 1 926 586 bearing components are already used proposed with self-lubricating effect from a mosaic structure exhibiting composites, in which the composite is a in the form of a flexible putty made of elastomers and

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Dipl.-Phys. Heinrich Seids · Patent Attorney · 62 Wiesbaden-Bierstadt · Bierst. Height 15 Postf. 120 68 ® (0 6121) 56 53

thermoplastic or thermosetting resins Should contain binders and solid lubricant particles.

The manufacture of these bearing components is difficult, however, tedious and expensive.

Ss are also plain bearings and processes for their production, for example from DT-AS 1 065 102 known, in which the overlay is made of porous, with polytetrafluoroethylene formed alone or in connection with metallic lead, indium, thallium or cadmium-filled metal framework is. However, these known bearings have the disadvantage that after the removal of the thin, beyond the metal frame going layer the metal framework becomes increasingly free, and correspondingly in increasing hatred strong wear causes on the counter-runner. The production method of these known bearings is particularly complex because initially a porous metal frame is created on the support body and this porous metal frame is coated with polytetrafluoroethylene or filled with a mixture of polytetrafluoroethylene and metal powder.

From US-PS 3,342,667 it is known, the overlay of a

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Dipl.-Phys. Heinridi Seids · Patent Attorney · 62 Wiesbaden-Bierstadt · Bierst. Height 15 · Postf. 120 68 ■ ® (0 6121) 5653

Plain bearing made of polytetrafluoroethylene and metal particles "formed by a thermosetting resin are connected. The resin should be both the polytetrafluoroethylene and the Metallte: lichen envelop. However, this well-known overlay has no good ones Running properties. Therefore, it should also be known for these Bearings, the running layer is kept porous and filled with liquid lubricant.

Finally, it is known to use plain bearings with a tetrafluoroethylene overlay filled with metal powder, in particular bronze powder in such a way that first a mixture of polytetrafluoroethylene powder and metal powder is sintered together to form a block, and that foils are then cut from this block and placed on the supporting body of the Bearing (PR-PS 1 303 584). Practice has shown that a sufficiently strong adhesion of the cut films is actually only achieved on the support body if an adhesion promoter, for example in the form of a poly made from a copolymer of tetrafluoroethylene and hexafluoropropylene. Nevertheless it is Production method of this known bearing is particularly complex, since in addition to the special production process with Metal powder-filled foils made of polytetrafluoroethylene

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Dipl.-Phy ·. Heinrich Sddf · PatcntanwtU · 62 Wlenlwden-BleriUdl · Blent. Height IS · PwIf. 120 ββ · φ (06121) 5 »53β2

also after connecting these foils to the supporting body as before causes considerable difficulties. In contrast, the invention is based on the object of creating a production price for plain bearings that is relatively simple and cheap, and nevertheless leads to plain bearing elements with particularly good bearing properties. The overlay, which is essentially composed of polytetrafluoroethylene, should have a particularly high adhesive strength have to the metallic support body.

This is achieved in the method according to the invention in that oine adhesion promoter layer made of at least one thermoplastic compound from the group of polytrifluorochloroethylene, polyvinyl fluoride or polyvinylidene fluoride, in particular of thermoplastic copolymer of tetrafluoroethylene and hexafluoropropylene in the form of powder or paste or a dispersion is brought to the back of the bearing and sintered on, and that this adhesive agent is applied a layer of polytetrafluoroethylene and optionally metal particles and optionally mixed with a copolymer Tetrafluoroethylene sintered on porous or a porous sintered film made of poly tetrafluoroethylene, possibly filled with Metal particles are applied and that the applied porous layer under pressure and temperature to form a

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DlpL-Ph, .. Heinrich 5, Id. P.l.nUnw.lt62 Wle.b.i.n-Bl.r.Udl Bler.t. Height 15 · Pdf. 12068 · «(06121) 565382

uniform bearing running layer is pressed into the adhesion promoter layer and compacted.

The method according to the invention can be carried out on a continuous basis Moving .Band carry out continuously, and leads to sliding bearing elements with very good sliding properties and good adhesive strength of the sliding layer on the support body, for example a steel back.

For a better understanding of the invention, some exemplary embodiments are explained below. In the drawing demonstrate:

Pig. 1 shows a section through a composite material strip provided for the production of slide bearings and

Pig. 2 shows a substantially enlarged section the line H-II of FIG. 1.

In the example shown in the drawing, a bearing runner 1 is attached to a steel tube 2. the Bearing running layer 1 is Like Pig. 2 shows, composed essentially of polytetrafluoroethylene particles 3 sintered together, which are substantially elongated in shape. she

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Dipl.-Phy ». Heinrich Selds · Patent Attorney · 62 Wiesbaden-Bierstadt · Blerst. Height IS Poslf. 12068 · "3? (061 21) 56 53

Particle size may be about 30 to 50 m. This running layer, which is essentially made up of polytetrafluoroethylene, is filled with metal powder particles 4, namely bronze particles of approximately the same size as the polytetrafluoroethylene particles 3, but with a spattered shape. The spaces 5 remaining between the metal particles 4 and the polytetrafluoroethylene particles 3 are filled with a thermoplastic binder, preferably a thermoplastic copolymer of tetrafluoroethylene and hexafluoropropylene. As shown in FIG. 2, the arrangement of the polytetrafluoroethylene particles 3 and metal particles 4 is shown in FIG. The free surface of the bearing running layer 1 becomes denser, while the spaces 5 become larger towards the bearing back 2. As a result, the binder contained in the spaces 5 is also effective as an adhesion promoter to the bearing back 2 and thus ensures a secure, firm bond between the bearing running layer 1 and the bearing back 2 the free surface 6, that is to say the bearing running surface, so that thermoplastic binding agent is still present there as well. The binder to be used according to the invention and also to be used as an adhesion promoter, however, is so closely matched to polytetrafluoroethylene in its corrosion properties and its frictional properties that it does so

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Dlpl.-Phy ». Heinrich Seid. · P «tent» nwall · 62 Wlesbiden-BiersUdl · Thirst. Height «15 · Poslf. 120 68 φ (06121) 5633 82

the binder present in the tread 6 No deterioration of storage properties. Despite the binder contained in its running layer 1, the bearing can operated completely maintenance-free. The often accepted particularly beneficial effect of plain bearings with Polytetrafluoroethylene running layer, after which the polytetrafluoroethylene degraded from the running surface 6 is on the bearing pin builds up into a thin, closed layer, can also still be present in the running surface 6 through the Adhesion promoter can be significantly improved, since this adhesion promoter also builds up a uniform on the bearing journal smooth layer of polytetrafluoroethylene favors.

The following examples can be considered for the composition of the bearing layer 1 applied to the primer:

Example 1t

16 wt. 5 »of a copolymer of Eetrafluoroäthylen and

Hexafluoropropylene

34% by weight of polytetrafluoroethylene

50 wt. I> tin-lead bronze ($ 80> Cu, £ 10 Sn, 10% Pb).

Example 2:

? 0 wt. I »polytetrafluoroethylene

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Dipl.-Phys. Heinrich Seids · Patent Attorney · 62 Wiesbaden-Bierstadt · Bierst. Height 15 · Postf. 120 68 ■ ^ f (0 6121) 56 53

40 wt. Fo tin bronze (90 # Cu, 10% Sn).

30 wt. Io copolymer

The particle size preferred in the present Pail was 35 Å in all cases .

The sliding layer produced in the manner described has very good adhesive strength to the metallic iräger on. The plain bearings made from the composite material show very good sliding properties and are maintenance-free.

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Claim e

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BATH ORIGINAL

Claims (2)

Dipl.-Phys. Heinrich Seids · Patent Attorney · 62 Wiesbaden-Bierstadt · Bierst. Height 15 · Postf. 120 68 · ® (0 6121) 56 5382 Claims M) 'Process for the production of self-lubricating sliding bearing elements with metallic!' Rager and a running layer made of a preferably metal powder-containing mixture of polytetrafluoroethylene and a thermoplastic compound as a binder, characterized in that a main mediator layer made of at least one thermoplastic compound from the group of polytrifluorochloroethylene, polyvinyl fluoride or Polyvinylidene fluoride, in particular made of a thermoplastic copolymer of tetrafluoroethylene and hexafluoropropylene in the form of powder or paste or a dispersion, is applied to the back of the bearing and sintered and that a layer of polytetrafluoroethylene particles and, if necessary, metal particles and, if necessary, a mixture with a copolymer of tetrafluoroethylene Ä len porous sintered or. a porous sintered film made of polytetrafluoroethylene, if necessary filled with metal particles, is applied and that the applied porous layer is un d temperature to form a uniform bearing running layer is pressed into the adhesion promoter layer and compacted. / 10 409882/0016 Dipl.-Phys. Heinridi Seids · Patent Attorney · 62 Wiesbaden-Bierstadt · Bierst. Height IS Postf. 120 68 & (0 61 21) 56 53 82 - 10 - 2) binder for use in the method according to claim 1 in the IOrm of a copolymer of tetrafluoroethylene and hexafluoropropylene, characterized in that its melting temperature is about 285 ° C. 409882/0016