JPS60210414A - Manufacture of wear-resistant composite material - Google Patents

Abstract

PURPOSE:To improve durability, by making only a part of a plastic molded material necessitating wear-resistant properties, which is superior in molding properties, into a state of ceramics. CONSTITUTION:The titled composite material is one to be obtained by making a wearing part of a plastic molded material into a thin layer of ceramics. In other words, the composite material is obtained by either molding plastics by making use of said molding tool or bonding said ceramic thin layer to the plastics or a metal by fitting a ceramic spray layer in a molding tool for plastic molding by making use of the ceramic thin layer obtained by removing a base material after the ceramic spray layer has been molded on the surface of the base material through plasma spraying. The ceramics to be applied to the composite material is either an individual or a mixture of oxides suchas alumina, zircon, zirconia, mullite, titania, chrome oxide, cordierite, spinel, and eutectic alloy of the alumina and the zirconia, to which an article whose particle diameter is less than 125mum, which is the quality of the material and the particle diameter to be used for conventional spraying, is applied.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a composite of ceramic and plastic or metal that has excellent wear resistance.

Because plastic molded bodies are lightweight and inexpensive, they are produced in large quantities (1) using methods such as injection molding and cast molding. Particularly recently, plastics have been widely used as engineering plastics and machine parts.

However, in mechanical parts such as sliding parts, movable parts, and parts that come into contact with abrasive powder fluids, where wear resistance is a key issue, durability becomes a problem because plastics are soft. Further, even if a composite resin in which ceramics are dispersed in plastic is used, this problem of wear cannot be solved.

If these parts are manufactured using ceramics as a material, wear resistance will be greatly improved, but ceramic parts have the drawbacks of being easily broken, having difficulty achieving dimensional accuracy, and being expensive. Furthermore, it is difficult to manufacture thin-walled ceramic products.

In practice, parts that require wear resistance usually become unusable even if a small amount of wear occurs. However, only a part of the part requires wear resistance, such as the surface part of the part. Therefore, it is possible (2) to inexpensively improve the durability of the entire part by making only the parts that require this wear resistance ceramic.

An object of the present invention is to provide a method of improving the durability of a plastic molded body having excellent moldability by making only the portions requiring wear resistance ceramic. That is, it is a composite body in which the parts of the plastic molded body that wear out are made of a thin ceramic layer.

In the present invention, after forming a ceramic sprayed layer on the surface of a base material by plasma spraying, the thin ceramic layer obtained by removing the base material is used, and this is fitted into a mold for plastic molding. to mold plastic using
This is a method of bonding the ceramic thin layer to plastic or metal to obtain a composite.

Since the ceramic 'NJ layer of the present invention is obtained by thermal spraying ceramic powder, the thickness of the ceramic thin layer can be changed as necessary, and the thickness can also be changed partially. It is possible. Since the ceramic thin layer obtained in this way is deposited once on the surface of the base material, the dimensional accuracy on the base material side is also characteristically extremely high.

(3) The ceramics used in the present invention are oxides such as alumina, zircon, zirconia, mullite, titania, chromium oxide, cordierite, spinel, alumina and zirconia, etc. alone or in combination, and the particle size is 125μ or less. The material and particle size used are those used for normal thermal spraying.

Plasma spraying is used for thermal spraying, which is suitable for ceramic materials with high melting points, but water plasma spraying is illegal compared to gas plasma spraying because it has a higher flame temperature, a wider flame pattern, and a larger amount of spraying per unit time. It is perfect for.

The spray thickness is controlled by the supply rate of material powder to the plasma flame and the moving speed of the plasma flame. It is possible to partially change the thermal spray thickness or change the type of thermal spray powder.

Thermal sprayed base materials differ depending on the method used to remove the base material after thermal spraying. Methods include burning and removing the base material as a combustible material, melting and removing the base material, dissolving and removing the base material with chemicals, etc., methods of hardening the base material with resin, etc. with resin, and breaking and removing the base material after thermal spraying. If materials are not to be reused, select and use the appropriate base materials for (4). The method described below is optimal for reusing the base material many times in its original form. That is, when there is a difference in the coefficient of thermal expansion between the base material and the sprayed layer, when the base material and the sprayed layer are cooled after spraying, the base material and the sprayed layer may be separated due to the difference in coefficient of thermal expansion. As a result of various studies,
It was found that if an appropriate temperature difference is applied and the difference in thermal expansion coefficient is 0.3% or more, the sprayed layer will separate from the base material without cracking and a thin ceramic layer will be obtained. . When the above-mentioned oxide is used as a powder for thermal spraying, metals are particularly useful as the material for the base material, and copper, stainless steel, aluminum, brass, etc., which have a not too low melting point and a high coefficient of thermal expansion, are preferable.

The ceramic thin layer obtained by the above method is fitted inside a mold for molding, a mold for side injection molding, a mold for compression molding, etc., and then a plastic material is cast or compression molded. At this time, in order to improve the adhesion between the ceramic and the plastic, the surface of the thin ceramic layer may be subjected to a blast treatment in advance. Alternatively, by injection molding or compression molding (5), the ceramic thin layer is adhered to the already molded plastic surface with an adhesive to form a ceramic-plastic composite product. Furthermore, this method of bonding a thin ceramic layer can be applied to metals as well as plastics.

If impact resistance as well as abrasion resistance is required when used as a mechanical part, the obtained ceramic thin layer may be impregnated with a resin. At this time, by selecting the type of resin, it is also possible to further increase the adhesive strength with the plastic. The types of resins to be impregnated include various resins such as epoxy, Teflon, phenol, and acrylic, and their monomers, and are impregnated by known means such as vacuum impregnation and coating. This resin impregnation may be performed before the ceramic thin layer and the plastic are combined, or after the ceramic thin layer and the plastic are combined.

By using the composite thus obtained in areas requiring wear resistance, durability that could not be obtained with conventional plastics mixed with ceramics (6) can be obtained.

The method of the present invention will be specifically explained below using Examples.

Example 1 Polished surface (1 knee 1: outer diameter 8 with plastinated after polishing)
A stainless steel nine bar of 0 mm SOS 304 was used as a shape 8, and while the shape 8 was not rotated, alumina-zirconia was sprayed to a thickness of 1.51 using an ice plasma spraying machine. When the shape 8 was cooled, it was removed to obtain a ceramic tube. An epoxy resin was poured into the tube and cured once to produce a composite.

This composite tube was cut into a length of 100 mm, and a hole of 12 mm diameter was punched in the center to obtain a roll having a thin ceramic layer on the surface.

For comparison, epoxy brass and 5S41 of the same shape
3 steel rolls were made, and 3 steel rolls were made on one shaft.
A wear resistance test was conducted by attaching a book roll and rotating the roll with the lower part of the roll immersed in a slurry of silicon carbide abrasive grain powder mixed with water. As a result, the wear degree of the outer diameter was 7 mm for the steel roll 1, compared to the product roll 0.1 mm according to the present invention (7).
, a plastic roll of 8 mm, demonstrating the excellent abrasion resistance of the product of the present invention.

Example 2 A copper rod with an outer diameter of 30 mm was used as a core material by water plasma spraying, alumina powder was sprayed, the core material was removed, and the thickness was 2 mm, and the length was 50 mm.
A circular tube of mm was obtained. This circular tube was heated at 1550° C. for 5 hours to change γ-A1UO8 to α-AlY0□, and then a rubber-based resin was impregnated into the tube and solidified.

The obtained circular tube was placed in the center and the periphery was solidified with ABS resin to obtain a composite of ceramics and plastics having ceramics on the inner surface.

In addition, a ceramic tube impregnated with rubber-based resin has an inner diameter of 36 mm.
A metal-ceramic composite was also produced by inserting it into a 5S41 steel material processed to mmφ and hardening the periphery with epoxy resin.

In order to compare the wear resistance of the obtained composites, holes with a diameter of 30.15 mm (same as the inner diameter of this example) were made in ABS plastic and 5S41 steel, and the holes were made with two unexplored (8) types. Plasto erosion was performed by spraying alumina powder together with air at an angle of approximately 30° onto the surface of the specimen.

As a result, the weight loss due to wear of the two products of the present invention was 0.3g, while the weight loss of the ABS plastic was 28g.
The g1 steel material weighed 7 g, indicating that the composite of the present invention has excellent wear resistance.

patent applicant Kyushu Firebrick Co., Ltd. (9) 1

Claims (2)

[Claims] (1) A ceramic sprayed layer is formed on the surface of a base material by plasma spraying, the base material is removed, the resulting ceramic thin layer is fitted into a mold, and the plastic is molded using the mold. A method for manufacturing a wear-resistant composite. (2) Production of a wear-resistant composite material characterized by forming a sprayed ceramic layer on the surface of a base material by plasma spraying, then removing the base material and adhering the obtained thin ceramic layer to the surface of plastic or metal. Method.