JPS5950177A - Surface treatment of metal giving superior adhesive property - Google Patents

Abstract

PURPOSE:To obtain a surface treating film having superior adhesive property and joining force by subjecting an ordinary surface treating film on a base material to hot hydrostatic pressing treatment. CONSTITUTION:An ordinary surface treating film such as a plated layer 2 is formed on a base material 1. The layer 2 is isolated from the open air and subjected to hot hydrostatic pressing treatment in a high temp. and high pressure gaseous atmosphere which is suitable for the joining of the layer 2 to the material 1 by diffusion, does not cause the reaction of them, and exerts no unfavorable influence on the material 1. Gaseous H2 or the like contained in the pores in the layer 2 is discharged, th layer 2 is joined to the material 1 by diffusion, and the layer 2 intrudes deeply into the material 1 and produces strong joining force.

Description

[Detailed description of the invention] The present invention relates to metal surface treatment methods.

Conventionally, plating is used to change the properties, dimensions, and appearance of the base material surface and improve resistance to discoloration and corrosion.

OVD (chemical vapor deposition), PyD (physical vapor deposition), vacuum evaporation. Various surface treatments such as thermal spraying are applied, but even though these treatments generally produce a uniform thin layer, the bonding strength between the base material and the thin film is generally very small, and problems such as constant peeling occur. Ta.

To explain this, for example, using plating, which is a typical surface treatment, plating is mainly used to make metal surfaces corrosion resistant, wear resistant, and glossy, but it has the following drawbacks: .

[1] As seen in Figure 38, there are many gaps (3) between the plating layer (2) and the base material (1).
2) There are pores (4) inside, which usually contain hydrogen, which weakens the strength.

(2) For example, if the purpose is to improve wear resistance, if the plating layer is thin, the plating layer will wear away quickly and sometimes peel off, exposing the base material.

(3) However, if it is thickly peeled, distortion will occur as shown in Figure 2, and for example, one thermal cycle will cause rf (
j j! A crack (5) is generated in the base material, and a crack (6) is also propagated to the base material.

(2) Also, once cracks occur on the surface of the plating,
'j! 4' Not only is the performance as tJ negligible, but it is also worse than when no plating is applied.

(5) In particular, if the plating peels off locally, electrolytic corrosion m()l)J different silk combinations will cause corrosion faster than when there is no plating. occurs.

(6) Once the plating is removed from decorative parts that require gloss, the surface will be lost and the overall value will decrease.

etc.

By the way, in recent years, 1) CVD, including the above-mentioned metallurgy.

PVD technology, vacuum evaporation, general irradiation, and other surface treatments 3 (I!) technologies are widely used in cutting-edge industries, and each plays an important role.
It is fulfilling lO. Among them, for example, the good bond between the thin film and the base material of technology C, which is currently widely used in various fields, plays an important role in terms of electrical and thermal properties.
A ceramic film such as Si3N4 or TiN is often attached to the thin film of the tool, and the bonding strength between the thin film and the base material depends on the f content of the tool. Moreover, recently, amorphous thin films have also been utilized in the electronics industry, and are expected to play a role in this field.

In this way, the surface treatment film has become a powerful material that provides a better future than the plating of the past, and although its multilayer properties are becoming more and more superior, its bonding strength is comparable to that mentioned above. As before, it is still weak, and the general-purpose technology that can solve this problem has not yet been developed.

However, recently 1. Hot isostatic pressing is a method for joining metal materials by compressing the object to be processed in the same direction under a high-pressure gas atmosphere of 11 [l] to produce a dense sintered body from metal powder, ceramic powder, etc. (hereinafter referred to as the HIP method) has been developed and is attracting attention? I was bathed in it. In particular, the conditions for diffusion bonding of metal materials using the HIP method (temperature, pressure, 1 hour)
However, if appropriate selection is made, it is possible to combine not only the same type of metal but also different types of metals, which is of interest from the standpoint of manufacturing individual composite materials today.

However, even though this HIP method is used, it cannot be used in general metal processing fields such as powder compaction, removal of sintering defects or casting defects, or reprocessing of carbon densification 2 alloy fatigue parts. However, no attempt has been made to firmly fix the thin film on the surface to the base material.

In view of the current situation described above, the inventors of wood have taken up the challenge of applying the HIP method to metal surface treatment, and have thereby succeeded in increasing the bonding strength of metal surface coatings, which had been considered one of the difficulties in the past. I decided to try the experiment.

That is, the present invention is a ventilation hole? The purpose of this method is to apply the HIP method to parts that have been subjected to a thin film surface treatment that does not have any curved surfaces on the base material, to increase the density and bonding strength of the parts, as well as to improve the fatigue strength of the treated parts. After forming a metal coating according to the treatment method, the member to which the coating is attached is kept isolated from the outside air, and Irx is suitable for diffusion bonding between the base material and the surface metal coating, but the two do not react and A hot isostatic press treatment (1) was applied to the part of the film to which it was attached under a high-temperature, high-pressure gas atmosphere that would not cause any unfavorable effects on the material.
11P processing).

Here, the usual surface treatment means include plating method, C
All known metal surface treatment methods such as the VD method, PVD method, vacuum evaporation method, and thermal spraying method are included, but in the present invention, H
Thermal spraying is not very suitable for metal coatings that are deposited in P treatment, as coatings without ventilation holes are most effective, and the most typical method is electroplating. Can be mentioned.

In this case, the base material is almost any metal.

Carbide materials, electrically conductive materials can be used, and L
′ (Plastic, carbon in the case of empty deposition.

Ceramic, glass, etc. can also be used. Furthermore, various metals suitable for vapor phase plating are used.

Almost all metals can be used for surface treatment, such as plating and vacuum deposition, but C! u, N], Or, Zm, Sn,
Pb, Pf;, A, l,.

Sb, Ccl, Co, Au, ■Y1. Ag, 7j
Also, in the case of vapor phase plating, Zr, Tj, W,
Nb and Ta can also be used sufficiently.

Then, metal surface treatment is performed using each of the above-mentioned 1 base material and 1 surface treatment material, and a metal coating is formed on the surface of the base material. Due to the lack of bonding force, the H process, which is an important process of the present invention, was not applied to this part.

HIP treatment usually uses a capsule made of mild steel or glass, which is charged into the metal coating attachment part A and the capsule 11, and the lid is removed by welding or the like.
The internal air is degassed by vacuum suction, and then the degassing tube is used. This is done by sealing the metal coating, placing it in a high-temperature, high-pressure furnace, and holding it under the required 1z wet high pressure. For example, the hydrogen scum contained in the hole is expelled, and the metal coating and the matrix are diffusion-bonded at their joint surfaces, and the metal coating, such as plating, penetrates deeply into the irregularities of the matrix, creating a strong bonding force. get.

Figure 3 is No. 1 by plating in contrast to Figures 1 and 2;
After surface treatment in 1 layer, 3 rows of 11 P treatment is applied. It was revealed that the gap (3) that existed between the matrix and the matrix (1) disappeared, and that the plating layer penetrated into the fiJ layer (7) and had a good bonding state between the two. ing.

Appropriate conditions for the treatment part fl in the above H/P treatment are selected depending on the material and the type or thickness of the metal coating, as well as the specifications of the surface treatment, but in general, when the base material and metal coating are The temperature must be suitable for diffusion bonding. However, it is important that the temperature is lower than the temperature at which the parent phase and the metal coating do not cause any adverse effects such as anti-lubrication [5] or unfavorable transformation to the parent material.Specifically, Sn, Z? When surface Uo treatment is applied to steel using mesokiio, such as No. 1, both the pressure and temperature are low, and it is possible to use pressures of 50° C. and 200° C. or more, but in the case of other metal surface treatments, it is almost 100 η.

A temperature of 300°C or higher is preferable.

Of course, as an aspect of the H-p treatment, it is not always necessary to use a container such as a capsule, and the gas is not limited to Ar gas, but may also be N.
2 It is also sufficient to use other inert gases such as gas.
It is possible.

In addition, the surface of the base material is not smooth and is usually uneven, but is this uneven surface the result of a metal coating on the surface?
Since it is possible to penetrate into the four parts and create a stronger bond q4), before surface treatment,
It is also effective to process one side.

Furthermore, the surface-treated metal coating to which the method of the present invention is applied has a coating thickness of 31S ('J), which has a wide range of thickness from 0.05μ to 50μ or more than that obtained by ordinary surface treatment. These (Kozu J
It can be practically applied in most cases.

In this way, the metal coating obtained by metal surface treatment such as plating as described above is firmly bonded to the base material, and at the same time, the pores in the metal coating or the gaps between the matrix 2 and the coating are crushed and disappear. However, the hydrogen gas contained in the same part escapes and reduces the adhesion and bonding strength by 10%, and also releases the hydrogen gas, which increases the fatigue strength of the treated part to the top and further exposes the base material. , sufficiently prevents cracking, etc.

Further specific examples of the present invention are listed below.

EXAMPLES Plated layers of the following particles were formed on the materials shown in the table below using an electrolytic plating method, and subjected to H-P treatment according to the following treatment conditions.

As can be seen in the margins below, the pores in the plating layer have disappeared in each of the above-obtained treated members, and moreover, the plating layer has penetrated into the matrix and has achieved an even stronger bond. Ta.

Moreover, although some difficulties were observed in Sample 2 after the above-mentioned processing section was removed, overall there was no cracking in the plating layer, and #! No J erosion was observed.

As described above, the method of the present invention has a bonding strength that cannot be obtained with conventional metal surface treatments such as plating.
511177 (4) A cutting tool that exhibits and improves adhesion and improves the fatigue strength of processed parts, and whose use will become increasingly important in the future. It is highly expected to be effective as a metal surface treatment method for sliding parts and decorative parts.

[Brief explanation of the drawing]

Figure m1 is a partial cross-sectional explanatory diagram showing the state of the joint between the plated layer and the base metal in the conventional method, and Figure 2 is the same (Crack development in the plated layer in conventional thick-walled plating? FIG. 3 is a partial cross-sectional explanatory view showing the state of bonding between the plated layer and the base material treated by the method of the present invention.

Claims (1)

[Scope of Claims] l After a metal coating is deposited on a base material according to a normal surface treatment method, the member to which the coating is attached is placed in a state shielded from the outside air, which is suitable for diffusion bonding between the base material and the surface metal coating. However, the adhesion is improved by subjecting the coating member to a hot isostatic press treatment 2 under a high-temperature, high-pressure inert gas atmosphere in which the two do not react and do not cause any unfavorable effects on the base material. Excellent metal surface treatment method. ! A metal surface treatment method with excellent adhesion according to claim 1, wherein the ordinary surface treatment means is plating treatment. 3 The metal coating formed on the base material is Ou, Ni, O
r, Zn. Sn, pb, Pt, At, Sb, Cd, (
! 3. The metal surface treatment method with excellent adhesion according to claim 1 or 2, wherein the metal surface treatment method is one or more metals or alloys selected from the metal group consisting of O, An, Ag, and Ag. The metal surface treatment method with excellent adhesion according to claim 1, 2, or 3, wherein the parent material is a material selected from the group consisting of metal, plastic, carbon, ceramic, and glass. 5. The metal surface treatment method with excellent adhesion according to claim 1, wherein the gas atmosphere is at a pressure of 50 psi or higher and 200° C. or higher. 6 The gas atmosphere has a pressure of 10 oy2. Above 300°C
A metal surface treatment method with excellent adhesion according to claim 1 or 5, which is as described above.