JPH02236285A - Metallizing method for supporting-body - Google Patents

Abstract

PURPOSE: To obtain coated articles useful for wear resistant applications of which the surface may be rapidly smoothed by subjecting a supporting body subjected to composite plating by a granular material-contg. electroless plating method to electroless plating.

CONSTITUTION: A friction textured disk of Al is, for example, cleaned and is subjected to a Zn treatment for the purpose of activation. This disk is then plated to about 19μ thickness in an electroless plating bath contg. 7g/L polycrystalline diamond of 6μ. The disk is thereafter, plated in the electroless plating bath not contg. the granular material and is heat treated for the purpose of improving the adhesion of the plating. This heat treatment does not change the roughness of the film. When the disk is brushed in order to smooth its surface, the same roughness as the case the second layer by the electroless plating is not formed is rapidly obtd. The release and striking fall of the outer particles do not arise.

COPYRIGHT: (C)1990,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION Composite electroless plated coatings are a new class of composites that can be derived via electroless plating techniques. The following patents and publications disclose the state of the art, the techniques used, and the particulate materials that can be incorporated into the electroless plating matrix: U.S. Pat.
No. 47, No. 3,753.667, Reissue 29.285
No., R. Barras et al., “Elect.
roles Nickel Coating-D
iamond Containirrg,Ele
ctrolesS Nickel Conference
ce, Cincinnati, Ohio, November
e r, 1 979, Muyobi British Patent 1,476,02
No. 4. These patents are incorporated herein by reference.

Although electroless plating can be applied to a wide variety of substrates, coatings of metal substrates may only achieve some of the properties of the initial substrate (e.g., corrosion protection, wear resistance, etc.). of great technical importance. However, plating can be carried out equally well on nonconducting and semiconducting substrates. Although the mechanism of composite electroless plating is not completely understood, it is believed that insoluble particulate matter suspended within the electroless plating composition is trapped during electroless plating deposition. For effective entrapment, the insoluble particles must attach themselves to the surface, allow normal electroless plating to run undisturbed, and encapsulate the particles without interrupting plating.

Therefore, the particulate matter is the actual (
Basic) R.M.L.
ukes, Plating, 5L 969 (1964
); (2) N. Feldsteinet al, J.
Electrochem. Soc. , 118, 869 (
1 97 1); (3) G. Salvago et.
al, Plating, 59, 665 (1972)), so that the particulate matter does not come into contact with the surface and fall from the surface into solution, but rather "sticks" to the surface.
However, it has been recognized that it is essential to provide good acquisition. The electroless nickel matrix has also been found to provide a "bond" for particulate matter entrapment. Moreover, it is undesirable for the particles to act as an autocatalyst.

Generally, particles in the range of 0.5 to 75 microns can be considered in the present invention. Furthermore, it is even more preferable to select particles with a narrow particle size distribution.

For most applications, the particles are generally in the range of 15-30% by volume, but especially when using high temperatures and/or high bath formulation concentrations, the particle concentration in the precipitate can be reduced to 40% by volume.
It can be more than % by volume.

In the case of diamond granules, especially polycrystalline diamond produced by explosive methods, the preferred particles can be chosen in the size range from 1 to 9 microns.

Table 1 describes the hardness of selected materials. The materials listed in Table 1 include diamond, silicon carbide, corundum, tungsten carbide, steel nitride, and hard chromium. Therefore, in anti-wear applications, it has a higher hardness compared to metal matrices derived by electroless plating or, as is known in the art, to Nickelson alloys, which reach hardnesses of approximately 69 Cucwell units with ripening. It is most effective to mix particulate materials with greater hardness compared to hardness materials or particles.

Diamond 10.000 Silicon Carbide 4 500 Corundum (ALOJ 2.4 0 0 Tungsten Carbide 1,300 Nitride Steel 1 110 Hard Chrome Plate 1,000 (Rc70) Nickel Phosphorus Alloy 950 (Rc69) Hardened Steel
900 (Rc62) P-2 steel
400 (Rc38) Particulate matter mixed electroless plating method and the article manufactured by this method I; will be described. The method and article are comprised of at least two distinct metal layers, the first of which contains particulate material, and the second of which is a metal layer substantially free of particulate material.

Articles of particular interest for which the present invention is particularly useful are those having cylindrical or disc geometry.

Articles (e.g. parts of textile machines) which may be used in or in which the invention may be practiced include friction texturing discs, spinnin rolls, etc. in the textile industry.
rotors (open end etc.) and rotors. Generally, these parts are circular, bell-shaped, cylindrical or multi-cylinder shaped. They are primarily used in jerky or rotational systems with directional movement of parts about an axis perpendicular to the plane of rotation.

In particular, the friction-textured disc used to impart the false twist has a multi-cylindrical geometry with an outer circumference, i.e. a portion that is actually in contact with the yarn and is slightly rounded or convex. (Textured
Yarn Technology/Volume
2. Stretch Yarn Machine
s, Monsanto Co. l967, G. D
．． Wilkinson (ed.), ATI. p. 16). The thread contact is partially perpendicular to the circumference of the part and parallel to the axis of rotation.

The spinning roll is cylindrical, in which the yarn contacts the outer circumference, parallel or unidirectionally, or perpendicular to the axis of rotation. The outside or actual circumference of this part usually contains the vias or teeth that perform the actual required functions.

The rotor (see US Pat. No. 3,439,487) is a bell-shaped article in which the thread contacts the bell or open end of the piece parallel to the axis of rotation.

Many of these materials are aluminum, aluminum alloys, or plastic, as they are lightweight, inexpensive, and relatively easy to shape. Other metal materials that can be used in the present invention, with the exception of aluminum alloys, include carbon steel alloys and tool steels, 400 series stainless steels, high speed steels, 300 series stainless steels, brass, copper and its alloys, nickel and its alloys. alloys, and combinations thereof.

The highest hardness (e.g. 6
Approximately 750°F (399°C) to achieve
The heat treatment should be carried out at a temperature of ). This heat treatment step, in addition to improving the adhesion of the metal layer to the support,
As is well known, hardening the matrix for alloys of the nickel phosphorous or nickel boron type.

In the metallization of parts of textile machinery, the final roughness of the coating is an important factor in order not to damage the threads in contact. At the same time, the inclusion of particulate matter in the wear-resistant coating increases surface roughness. The resulting surface roughness is proportional to various parameters, such as particle size, concentration of particles in the coating, plating thickness, and initial roughness of the support.

Smoothing of the final coating with a metal matrix and particles is an accepted procedure in order to meet the "smoothness" requirements in textile machinery applications, especially in texturing. For example, by brushing,
When carried out, release and knock-off of the outer particles occurred. This procedure is time consuming and costly as the wear resistant particles are very hard (eg diamond). It would thus be highly desirable to provide a coated article in which brushing time is reduced and the resulting product is useful in anti-wear applications.

To illustrate the invention, an aluminum friction textured disc was used. The discs were cleaned and zincated for activation, then 7 g/
A commercial electroless plating bath (Enplate 41) mixed with Q's 6 micron polycrystalline diamond (a product of explosive method)
5, Enthone, fnc. products) plated inside. This bath was used at 82°C and plated to a thickness of about 19 microns. Several disks were then plated in an electroless plating bath substantially free of particulate matter.

In actual experiments, the electroless plating bath was Niculoy
22 (manufactured by Siplay Company) and contained no particulate matter. The parts were plated for 0-2 hours under the conditions recommended by the seller. To improve adhesion, a heat treatment step was carried out to obtain a matrix hardness of approximately 69 Rc.

It is observed that the heat treatment process does not change the roughness of the film. Table 2 lists the roughness obtained by varying the brushing time. It can be seen that although some of the coated parts had higher surface roughness (when freshly plated) compared to the control, their roughness decreased more rapidly when brushed for an equal amount of time.

Although there are many electroless plating formulations that can be deposited as the final layer, shiny deposits are preferred ("Moder
n Electroplating” 3rd edition, R.
(See Lowe nhe im, ed., chapter 31, and references contained therein).

Thus, the article produced according to the invention comprises at least two layers, in particular a first layer which is a composite containing particulate matter and a second layer which is substantially free of particulate matter. is recognized.

Generally, the second layer has the same composition as the composite layer, but preferably is free of particulate matter. Moreover, because of the typical properties of the coatings of the present invention, even if the outer layer wears away, it will still result in a useful article that can withstand wear in use.

Although diamond has been used in the above description, it is clear that other particulate materials can be used for wear resistance and/or lubrication purposes. Such uses fall within the scope of this invention.

Claims (1)

[Claims] 1.1) Contacting the support with an electroless plating bath further containing insoluble suspended particulate matter to coat the support with a member selected from the group consisting of metals, alloys, and mixtures thereof. , insoluble particulate material, and subsequently 2) contacting said treated support with an electroless plating bath;
1. A method for metallizing a support, characterized by forming a layer consisting of a member selected from the group consisting of metals, alloys and mixtures thereof and substantially free of particulate matter. 2. The method according to claim 1, wherein the support is aluminum. 3. The method according to claim 1, wherein the support is an aluminum alloy. 4. The method according to claim 1, wherein the electroless plating bath is of the nickel phosphorus type. 5. The method according to claim 1, wherein the composite electroless plating bath is of the nickel phosphorus type. 6. Claim 1 in which the particulate material is wear-resistant particles
The method described in section. 7. Claim 1 in which the particulate material is diamond
The method described in section. 8. The method according to claim 1, wherein the particulate material is polycrystalline diamond. 9. The method according to claim 1, wherein the support is a friction texturing disk used in textile machinery. 10. The method of claim 1, wherein the support is aluminum or an aluminum alloy and the component is a rotor for use in textile machinery. 11. Further smoothing the support after metallization, 10-2
Claim 1: The surface roughness is within the range of 0AA units.
The method described in section.