DE102005036690A1 - Composite material consists of a glass fibre reinforced epoxy resin carrier layer, and a gliding layer on top - Google Patents

Abstract

A composite material consists of a glass fibre reinforced epoxy resin carrier layer and a gliding material layer on top. The gliding material consists of epoxy resin and a solid lubricant. The gliding layer contains at least one layer of polyester web material impregnated in the gliding material.

Description

The The invention relates to a composite material for sliding applications glass fiber reinforced epoxy resin base coat and a slip layer applied thereto, which is a sliding layer material made of epoxy resin and solid lubricant. The invention relates also on a manufacturing process.

With Such maintenance-free, self-lubricating high-performance sliding materials can be realized slide bearing concepts that are reliable over long periods of time work.

These Composites are used in applications with high, long-lasting static and dynamic load for use, in relatively low sliding speeds, with rotating, angular, axial or linear motion, e.g. then, if a conventional one Lubrication not possible or not allowed or other requirements in terms of wear resistance, resistance against operational and environmental influences as well as special items etc. are available.

A known composite material which is sold under the brand name devatex ^®, is a self-lubricating, glass fiber reinforced composite material, which is manufactured in a special winding technology. The base layer provides high strength, while the overlay contains special nonabrasive fibers and solid lubricants that provide excellent tribological properties even in humid environments with possible edge pressure. The solid lubricants stored in them also ensure extremely low friction values and wear rates in dry running.

When Applications of these composite materials come hatch, control rings for water turbines or end plates in wind turbines in question.

The Sliding layer usually has a thickness of about 0.5 to 2 mm. The application of the liquid sliding layer material requires framework with the desired Dimensions that are placed on the base course material. This Method is relatively expensive, because for each size of the plates to be produced or slices corresponding frames must be kept.

It is also desirable be able to produce the sliding layer in any thickness, in order higher Lifetimes due to greater wear layer thicknesses to achieve.

task The invention therefore is to develop this composite material in such a way, that any sliding layer thicknesses are adjustable. Also should the Production of the composite material in different dimensions be possible in a simple way.

These Task is solved with a composite material, which characterized is that the sliding layer of at least one layer of sliding layer material soaked Polyester fabric exists.

The Use of a polyester fabric for the sliding layer has the Advantage that the overlay can be prefabricated by webs be soaked in polyester fabric with the sliding layer material. This web-shaped Sliding layers can according to the size, for example the plate to be produced, cut and then opened the glass fiber reinforced Base layer to be applied by the webs or blanks be applied and pressed. There is thus the possibility To put one or more of these layers on each other, so the desired sliding layer thickness to achieve. Sliding layer thicknesses of up to 100 mm are easy produced. Polyester fabric also has the advantage of being not abrasive.

The Polyester fabric does not affect the properties of the overlay and serves only as a carrier material for simplified production of the sliding layers.

The Epoxy resin of the sliding layer can with the epoxy resin of the base layer be identical. But there is also the possibility of different Materials for this to use.

Preferably The polyester fabric has 20 to 30 warp threads and 10 to 17 weft threads. Especially are 25 to 30 warp threads, in particular 25 warp threads, and 14 to 17 weft threads, in particular 14 weft threads, prefers. It has been shown that because of the different Number of warp threads and wefts the tribological and mechanical properties of the composite material across from the composites of the prior art can be improved could.

Preferably are the solid lubricants PTFE and / or graphite.

Of the Proportion of solid lubricants based on the sliding layer material is preferably 16 to 25 wt.%.

The PTFE content based on the sliding layer material is preferably 16 to 18 wt.%, In particular 17 to 17.5 wt.%.

Of the Graphite content based on the sliding layer material is preferably 1 to 3 wt.%, In particular 1.8 to 2 wt.%.

The relationship from PTFE to graphite is preferably 1: 9.

preferred Uses of the composite material are for passive brakes, azimuth bearings in wind turbines, shipbuilding, in particular hatch covers, rudder stockyards, Expansion bearing for expansion tubes, Spherical plain bearings, construction machinery, water turbine nozzles, Kaplan hubs, Control rings, thrust washers, iron and tram applications, eg. Bogies, Rolling supports as well for the Automobile construction provided.

• – Herstellung eines Tragschichtprepregs, wobei ein Glasfasergewebe mit Epoxydharz getränkt und anschließend getrocknet wird,
• – Herstellung eines Gleitschichtprepregs, wobei ein Polyestergewebe mit einem Gleitschichtmaterial aus Epoxydharz und Festschmierstoff getränkt wird,
• – Verbinden mindestens einer Lage des Gleitschichtprepregs mit mindestens einer Lage des Tragschichtprepregs.

The method of making this composite for sliding applications involves the following steps:

• - Production of a base layer prepreg, wherein a glass fiber fabric is impregnated with epoxy resin and then dried,
• - production of a sliding layer prepreg, wherein a polyester fabric is impregnated with a sliding layer material of epoxy resin and solid lubricant,
• - Connecting at least one layer of the Gleitschichtprepregs with at least one layer of Tragschichtprepregs.

Preferably is for the production of the Gleitschichtprepregs a polyester fabric with 25 to 30 warp threads and 14 to 17 wefts used.

Preferably The prepregs are produced in webs.

to Production of plates is preferably a predetermined number blanks of prepregs under pressure and temperature. About the Number of blanks and thus over the number of individual layers of both the Tragschichtprepregs as In particular, the Gleitschichtprepregs can the thickness of the plate and also the thickness of the sliding layer depending on the desired requirements be set.

The Thickness of the sliding layer prepreg is preferably 0.1 to 3 mm, preferably at 0.1 to 0.2 mm, in particular at 0.15 mm, so that the thickness of the sliding layer in these gradations up to any Sliding layer thickness can be produced. The thickness of the sliding layer is preferably ≥0.5 mm.

at The production of pipes is initially a predetermined number of layers of Tragschichtprepregs wound on a mandrel and subsequently becomes a predetermined number of layers of the sliding layer prepreg wound on the Tragschichtprepreg, followed by the Prepregs are cured together with the mandrel. Subsequently, will The mandrel is removed and the tubes can, for example, be sockets be further processed.

The Advantages of the composite material are especially in the geometric variability of the material. Possible Variants are therefore z. As sliding plates, bushes, flanged bushes or also solid parts, which through a subsequent processing to elaborate Share, such. As balls and conical parts are processed can.

in the Manufacturing process, there are no restrictions in terms of economic Manufacturability and geometric possibilities, various To produce dimensions. The composite material is both screwable as well as stickable.

Around the material regarding To characterize the tribological properties were test bench tests on the test stands VR1, VRP1, VRS1 and VRU performed.

VR1 is a test bench for sliding plates the dimension 100 × 40 mm. The maximum load is 250,000 N. The temperature is at room temperature. The sliding speed is a maximum of 0.07 m / s. The maximum bearing load is 50 MPa. An oscillating translatory movement is carried out.

Of the test bench VRP1 is a socket tester for sockets with 70 to 90 mm diameter. The maximum specific bearing load is 140 MPa. The experiments are in a temperature range from -20 ° C to room temperature carried out. The sliding movement is an oscillating rotational movement. The Sliding speeds are from 0.001 to 0.01 m / s.

Of the test bench VRS1 is a socket tester for vibration simulation for Sockets with dimensions between 100 and 120 mm in diameter. The maximum load is 900 kN. The test temperature is at room temperature. It becomes an oscillating rotational movement carried out. The maximum sliding speed is 0.01 m / s.

In Diagram 1, the friction coefficient and the wear rate are a function of the bearing load represented. The measurements were carried out on the VR1 test stand. With increasing surface pressure, the coefficient of friction decreases, while the wear rate increases. At 100 MPa specific load, a friction coefficient of 0.055 μm was determined. The wear rate at this value was 233 μm / Rkm.

in the Diagram 2 is the comparison of the tribological properties in Dry running and wetting with water depending on the specific load shown. The addition of water caused only a slight reduction of the coefficient of friction on μ = 0.07 and an increase to 51 μm / Rkm.

The review of cylindrical bushings in terms of tribological properties was put to the test VRP1. The bushings had an inside diameter of 70 mm and a Length of 40 or 50 mm. The chosen one Running play was in the range of 120 microns to 150 microns. In the diagram 3, the friction coefficient and wear rate are a function of the specific Loading the sockets shown.

For the experiments with plain bearings only sliding layer material was used. The outer spherical surface of the test stand VRS1 moves in a receptacle with a recess. This Mating material has a hardness from about 175 HB. The results of this experiment are in the diagram 4, which compares the tribological properties at shows different specific loads.

The Results show that the material of the invention with up to 100 MPa specific load can be applied. At low surface pressures one finds relatively high coefficients of friction in the range of 0.25 μ, with increasing load down to 0.08 μ. In return, it rises the wear rate of 12 μm / Rkm at 10 MPa to 81 μm / Rkm at 100 MPa of specific loads.

Of the Temperature range from -80 ° C to 120 ° C is only dependent of the type of epoxy resin used. It is preferably a curing at high temperatures Epoxy resin. In particular, the tests with spherical bearings on the test bench VRS1 clearly show the performance of the material.

Claims (11)

Composite material for sliding applications of a glass fiber reinforced epoxy resin base layer and a sliding layer applied thereon comprising a sliding layer material of epoxy resin and solid lubricant, characterized in that the sliding layer consists of at least one layer of polyester fabric impregnated with sliding layer material. Composite material according to claim 1, characterized the polyester fabric has 20 to 30 warp threads and 10 to 17 weft threads. Composite material according to claim 1 or 2, characterized that the solid lubricants are PTFE and / or graphite. Composite material according to one of claims 1 to 3, characterized in that the proportion of solid lubricants based on the sliding layer material 16 to 25 wt.% Is. Composite material according to one of claims 1 to 4, characterized in that the PTFE content based on the total sliding layer material 16 to 18 wt.% Is. Composite material according to one of claims 1 to 5, characterized in that the graphite content based on the Total slip layer material 1 to 3 wt.% Is. Method for producing a composite material for sliding applications with the following steps: - Production a Tragschichtprepregs, wherein a glass fiber fabric with epoxy resin soaked and dried, - Production a Gleitschichtprepregs, wherein a polyester fabric with a Sliding layer material is impregnated with epoxy resin and solid lubricant, - Connect at least one layer of the Gleitschichtprepregs with at least one Position of the base layer prepreg. Method according to claim 7, characterized in that that a polyester fabric with 25 to 30 warp threads and 14 to 17 weft threads is used. Method according to claim 7 or 8, characterized that the prepregs are made in webs. Method according to one of claims 7 to 9, characterized that for the production of plates a predetermined number of blanks of Prepregs are connected under pressure and temperature. Method according to one of claims 7 to 9, characterized in that for the production of pipes, a predetermined number of layers of Tragschichtprepregs is wound onto a mandrel, that then a predetermined number of layers of the Gleitschichtprepregs is wound onto the Tragschichtprepreg and that the Pre to be cured on the thorn.