JPH06136563A - Metallic composite member - Google Patents

Abstract

PURPOSE:To improve the wear resistance and the fatigue strength of a metallic composite member by forming it by a matrix layer constituted of a metallic composite material in which fibers and/or grains are dispersed and a surface layer obtd., e.g. by coating the same with ceramics. CONSTITUTION:This metallic composite member is formed by a matrix layer 1 and a surface layer 3 obtd. by impregnating or coating the same with ceramics (such as titanium oxide, silicon oxide, yttrium oxide, zirconium oxide). The matrix layer 1 is formed by the metallic composite material in which a dispersion strengthening material 2 (such as Al (alloy), Mg (alloy), Ta (alloy)) constituted of fibers and/or grains are dispersed. Then, the surface roughness of the matrix layer 1 is regulated to 2 to 60mum Rmax, and the dispersion strengthening material 2 is protruded on a part of the surface of the matrix layer 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal composite member, and more particularly to a metal composite member excellent in wear resistance and fatigue strength.

[0002]

2. Description of the Related Art Light metals such as aluminum, magnesium, tantalum and titanium are widely used as industrial materials in various fields because they are light in weight, excellent in workability and castability, and inexpensive. It is used. In particular, as an alternative material to iron in the automobile industry, aircraft industry and electrical machinery industry, where weight reduction of equipment and parts is required, and in the food industry and construction industry where rust resistance is required from the viewpoint of aesthetics and hygiene. Application is progressing.

On the other hand, sliding members of various machines used in the automobile industry, aircraft industry, etc. are required to have various characteristics such as strength, rigidity and wear resistance. Was commonly used. However, for example, in an engine for an automobile, high performance,
Since high efficiency, low vibration, low noise, etc. are further required, it is required for the sliding members used for them to be lightweight while maintaining the characteristics of the sliding members. . In particular, for gears and bearings used under high-speed or high-load environments where alloy steel (quenched) or heat-treated steel (salt bath or gas nitriding) has been conventionally used because a high surface pressure of 600 MPa or more is required. In recent years, sliding members have also been required to have higher performance, higher efficiency, lower vibration and lower noise, and accordingly, have been required to be lighter in weight.
For this reason, it has been attempted to use a light metal such as aluminum, magnesium, tantalum, or titanium for the sliding member.

However, a light metal such as an aluminum material (aluminum and aluminum alloy) is a metal having characteristics such as softness, low melting point, active metal, and good conductivity, but is inferior in wear resistance, corrosion resistance and insulation. Is.

From the above, in the devices and parts used in the automobile industry, the aircraft industry, etc., in particular, the sliding members for high surface pressure, while maintaining various characteristics of the aluminum material such as lightness and workability, It is required to improve wear resistance, fatigue resistance, corrosion resistance and insulation.

Therefore, as one means for imparting wear resistance, corrosion resistance and insulation to aluminum materials, it has been attempted to improve the characteristics such as wear resistance by surface-treating the aluminum materials. There is.

As such a surface treatment, a plating method such as an alumite treatment, a hard chrome plating treatment, an electric nickel plating treatment, a hard anodic oxidation method, a thermal spraying method and the like are known. However, since the coating film obtained by the alumite treatment, hard chrome plating treatment, or electric nickel plating treatment has a maximum film thickness of about 10 μm, sufficient abrasion resistance required for high surface pressure sliding members can be obtained. No
In addition, the characteristics such as corrosion resistance, insulation, and welding resistance were also insufficient. Further, although the surface treatment by the hard anodic oxidation method gives the aluminum material a certain degree of wear resistance, corrosion resistance, insulation and welding resistance, for example, conventional alloy steel (quenching) or heat-treated steel (salt bath or gas When it is used as a sliding member that requires a high surface pressure of 600 MPa or more, which has been used for nitriding, there is a problem in fatigue characteristics that cracks are generated and adhesion to an aluminum material is insufficient and peeling easily occurs. . Further, the thermal spraying method has a problem of poor corrosion resistance.

On the other hand, there is ceramic coating as a surface treatment technique for improving the heat resistance and wear resistance of the surface layer. Ceramic coating is a method for forming a film by fusion bonding ceramics mainly composed of alumina, silica, boron oxide, etc. to the surface of an object, and in particular, coating with Cr ₂ O _{3 having} a high melting point and a high hardness ( Below, TOSR
IC coating (registered trademark)) provides heat resistance and abrasion resistance to a metal surface. This coating layer is a processing method for forming a surface layer containing chromium oxide as a main component converted from a chromium compound by heating on the surface of a metal base material, for example, applying a CrO ₃ aqueous solution to the surface of the base material,
It is obtained by heating at 400 to 500 ° C. to precipitate Cr ₂ O ₃ . The TOSRIC coating has conventionally exhibited its characteristics as a coating on an iron-based base material.

However, if an attempt is made to coat the aluminum material in the same manner, the base layer made of the aluminum material and the surface layer made of chromium oxide are separated during the heat treatment in the coating step, so that Cr ₂ O is applied to the aluminum material. I couldn't coat ₃ .

Therefore, the present inventors consider that the cause of the peeling is the stress acting between the base layer and the surface layer, and in order to relax the stress applied to this coating layer, a hard layer is formed between the base layer and the surface layer. An attempt was made to provide a stress relaxation layer by a surface treatment such as chrome plating, hard anodic oxidation, electric Ni plating, electroless Ni plating. However, peeling occurred not only at the surface layer-plating interface but also at the plating-base layer interface, and the intended effect was not obtained.

[0011]

As described above, the aluminum material obtained by various surface treatments has some wear resistance, corrosion resistance, insulation property, welding resistance and adhesion property.
When used as a sliding member for high surface pressure used in an environment such as high speed or high load that requires an allowable surface pressure of 00 MPa or more, abrasion resistance becomes insufficient and cracks occur because the base layer is soft. However, there is a problem in that the base layer and the surface layer are liable to peel when the ceramic coating is applied.

The present invention has been made to solve the above problems, and has sufficient wear resistance and fatigue resistance as a metal composite member excellent in wear resistance and fatigue resistance, especially as a sliding member for high surface pressure. It is an object to provide a metal composite member having properties (crack resistance and peeling resistance) and the like.

[0013]

MEANS FOR SOLVING THE PROBLEMS A metal composite member of the present invention comprises a base layer made of a metal composite material in which fibers and / or particles are dispersed, and a surface layer obtained by impregnating or coating the base layer with ceramics. It is characterized by having and.

The inventors of the present invention have conducted extensive studies to solve the above-mentioned problems, and as a result, when a metal composite material in which fibers and / or particles are dispersed in a base layer is used, the base layer is impregnated with ceramics or a core. In addition, it has excellent wear resistance, corrosion resistance, insulation, welding resistance, and adhesion that can withstand use as a sliding member requiring a high surface pressure of 600 MPa or more, which is the object of the present invention. It has been found that a metal composite member can be easily obtained.

If the substrate is used under severe conditions, the surface of the base layer may be chemically or mechanically treated as necessary.
It was found that when the surface roughness is -60 μmRmax, the adhesion strength between the base layer and the surface layer is further increased.

That is, by forming the base layer from a metal composite material, ceramic coating becomes possible, and while utilizing the characteristics of light metals such as aluminum, magnesium, tantalum, and titanium, the wear resistance and fatigue resistance as described above are further achieved. Improved properties (peeling resistance, crack resistance), and by processing the surface roughness of the base layer to 2 to 60 μmRmax, more superior wear resistance and fatigue resistance can be obtained stably and easily. Found out.

That is, the surface roughness of the base layer of the metal composite member of the present invention is preferably in the range of 2 to 60 μmRmax. If the surface roughness of the base layer is less than 2 μmRmax, the wear resistance and crack resistance, peeling resistance, and other fatigue resistance characteristics applicable to the sliding members for high surface pressure, which is the purpose of the present application, cannot be obtained, and 60 μmR
When it is larger than max, it affects the surface roughness of the surface layer. The range is more preferably 3 to 40 μm Rmax, and further preferably 5 to 20 μm Rmax. Here, as the base layer having the above surface roughness, there are three typical examples as shown in FIG. 1, FIG. 2, and FIG. FIG. 1 shows a structure in which a base layer made of a metal composite material in which fibers and / or particles are dispersed is impregnated with or coated with ceramics.

FIG. 2 shows a structure in which a base layer in which at least a part of fibers and / or particles are projected is impregnated or coated with ceramics. Such a structure can be obtained, for example, by subjecting the surface of the metal composite material forming the base layer to a chemical treatment such as deep etching. Here, in the structure in which the reinforcing material protrudes from the base layer as shown in FIG. 2, the amount and length of the protruding reinforcing material that provides wear resistance and fatigue resistance are appropriately controlled depending on the purpose of use. can do.

FIG. 3 shows a structure in which a base layer having holes formed on at least a part of the surface of a metal composite material is impregnated with or coated with ceramics. Such a structure is obtained, for example, by subjecting the surface of the metal composite material to mechanical treatment such as dry honing. Here, the hardness, thickness, pore size, and number of pores per unit area of the base layer can be controlled during the formation of pores or during the impregnation or coating process. The level of insulation, welding resistance, lubricity, chemical resistance, weather resistance, etc. can be adjusted according to the purpose of use. The size of the holes is preferably a size suitable for the ceramic to be impregnated or coated.

Further, the volume ratio of the dispersion reinforcing material contained in the matrix layer constituting the metal composite member is preferably in the range of 5 to 35%. If the volume ratio of the dispersion reinforcing material contained in the matrix layer constituting the metal composite member is less than 5%, the wear resistance, crack resistance, and peeling resistance applicable to the sliding member for high surface pressure, which is the object of the present application, can be achieved. The fatigue resistance characteristics such as
If it is more than%, it becomes difficult to disperse it efficiently in the aluminum alloy which is the matrix. A more preferable volume ratio is in the range of 7 to 30%, and further preferably 10 to
It is in the range of 30%.

As the matrix material of the metal composite material of the present invention, a light metal such as aluminum or aluminum alloy, magnesium or magnesium alloy, tantalum or tantalum alloy, titanium or titanium alloy can be used, and particularly aluminum or aluminum alloy. Is preferably used.

Here, as the aluminum or aluminum alloy of the present invention, various high strength aluminum alloys can be used, and examples thereof include alloys containing components such as Si, Mg and Cu. As such an aluminum alloy, for example, among JIS standard aluminum alloys,
1100Al alloy, 6061Al alloy, 5052Al alloy, 7075Al alloy, 40
32Al alloy, (2024Al alloy), ADC4A alloy, ADC8A alloy,
Examples include ADC10 alloy and ADC12 alloy.

As the reinforcing material such as inorganic fibers dispersedly contained in the matrix material, whiskers such as alumina, silicon carbide, silicon nitride, aluminum titanate, aluminum borate, and mullite, fibers, and particles are used. it can.

Further, in the metal composite member of the present invention, at least a part of the surface of the base layer is impregnated or coated with ceramics, which have abrasion resistance, corrosion resistance, insulation property,
Those having excellent welding resistance, lubricity, chemical resistance, weather resistance and the like are preferable. Examples of such ceramics include
Titanium oxide, silicon oxide, yttrium oxide, zirconium oxide, aluminum oxide, chromium oxide, boron oxide,
Examples thereof include lead oxide, tin oxide, antimony oxide, titanium nitride, silicon nitride, silicon carbide, tungsten carbide, titanium boride, sialon, enamel, and compounds thereof. Especially among ceramics, T using Cr ₂ O ₃
The OSRIC coating has a permissible surface pressure of 800 MPa or more, and is therefore particularly preferable as the sliding member for high surface pressure intended by the present application. The metal composite member according to the present invention can be obtained, for example, by the following manufacturing method.

First, an aluminum-based composite material containing fibers and / or particles having a volume ratio of 5 to 35% is used as a base material,
A base layer having a desired surface roughness is formed on the surface of the base material by a chemical or mechanical method. Then SiO _2, the slurry was added for Al ₂ O ₃ main components CrO ₃ on the surface of the base layer - liquid impregnation or co - after deposition by means such as coating, heated at a temperature of 400 to 500 ° C. -Baking to form a surface layer containing Cr ₂ O ₃ as a main component. Further, a 60% by weight aqueous solution of CrO ₃ is adhered to the surface of the base layer after baking by means such as impregnation or coating, and heated and baked at a temperature of 400 to 500 ° C. In this way, the step of adhering the CrO ₃ aqueous solution and the firing step are combined to form one cycle, and by repeating this cycle a plurality of times, SiO ₂ and Al ₂ O ₃ are used as aggregates on the surface of the base layer, and Cr ₂ O ₃ is the main component. It is possible to form a surface layer having excellent compactness, wear resistance, surface smoothness, and adhesion. If the thickness of the surface layer is less than 10 μm, sufficient wear resistance as a sliding member for high surface pressure cannot be obtained, and if it is greater than 60 μm, sufficient adhesion to the base layer cannot be obtained, and fatigue resistance strength becomes a problem. Since it occurs, the thickness is preferably 10 to 60 μm. More preferably, it is in the range of 30 to 50 μm.

[0026]

In the metal composite member of the present invention, since the metal composite material in which fibers and / or particles are dispersed is used in the base layer, even if a soft metal such as an aluminum material is used as the matrix material, its light weight characteristic is obtained. It is possible to easily increase hardness, strength and rigidity while maintaining the above, and it is possible to easily obtain wear resistance and crack resistance that can be used as a sliding member for high surface pressure. Further, if necessary, if the surface roughness of the base layer is set in the range of 2 to 60 μmRmax and the surface layer is formed by impregnating or coating with ceramics, more excellent adhesion between the base layer and the surface layer can be obtained. To be
Therefore, the characteristics of the aluminum material that is lightweight and excellent in workability, as well as the wear resistance of the ceramic coating,
While maintaining properties such as corrosion resistance, insulation, welding resistance, lubricity, chemical resistance, and weather resistance, it is used under high-speed or high-load environments that require an allowable surface pressure of, for example, 600 MPa or more. It is possible to improve the wear resistance and fatigue resistance of the sliding member for surface pressure.

[0027]

EXAMPLES Next, examples of the present invention will be described.

Example 1 First, a base layer was manufactured. The base layer is an aluminum composite material, and mullite whiskers are used as a dispersion reinforcing material.
Mullite whisker preform (volume ratio about 25%)
Was mounted on the die of a die-cast machine, and ADC12 alloy was injected and impregnated. For the impregnation by die casting method, the melt temperature is 700 ~ 750 ℃, the injection speed is 0.1 ~ 1.5 m / s, the pressure is 650 ~.
750kgf / cm ² , Mold temperature is about 300 ℃, diameter is 50mm,
We made a mullite whisker reinforced aluminum alloy composite material with a height of 60 mm and a weight of 380 g. The resulting composite material has a tensile strength: 42 kgf / mm ² , Young's modulus: 11000kgf / mm ² ， Hardness: HV
200, base metal ADC12 alloy (tensile strength: 32k
gf / mm ² , Young's modulus: 7500kgf / mm ² , Hardness: Strength, Young's modulus, and hardness were improved compared to HV90). Subsequently, this surface was subjected to dry honing to form a base layer having a surface roughness of about 7 μmRmax. Next, a ceramic slurry liquid consisting of Cr ₂ O ₃ , Al ₂ O ₃ , SiO ₂ and water was applied to this surface and baked at 450 ° C. Subsequently, a 60 wt% CrO ₃ aqueous solution was applied to the surface layer and then baked at 450 ° C. This CrO ₃ aqueous solution coating / firing process is defined as one cycle, and this cycle is repeated 19 times,
A surface layer having a thickness of about 50 μm was formed.

Next, the obtained metal composite member was used to measure the allowable surface pressure, wear reduction and fatigue strength. The wear loss was measured under the conditions shown in Table 2 and the fatigue strength was measured under the conditions shown in Table 3.

As a result, as shown in Comparative Example 5 in Table 1, the conventional TOSRIC coating (registered trademark) was not possible on the aluminum material, whereas the composite material was used as in the present invention. If it is, you will be able to coat it.
It has a high allowable surface pressure of 800 MPa, which is almost equivalent to that of a quenched alloy steel, and a fatigue strength of 200 MPa (10 ⁷ It can be seen that excellent wear resistance and fatigue resistance can be obtained even under sliding conditions at high surface pressure, which was difficult with conventional aluminum alloys by surface treatment. It can be seen that the metal composite member of the present invention provides excellent wear resistance and fatigue resistance. Further, if the die casting method is used as in the present embodiment, it is possible to perform a surface treatment on a part of the composite material in the shape of a near net, which is excellent in mass productivity.

Example 2 First, a base layer was manufactured. SiC Wis as a dispersion strengthener
Use a car to atomize the aluminum alloy 6061 alloy atomized powder.
After mixing 1% by weight of rucor, it was filled in a graphite mold.
200 kgf / cm at room temperature² Was pre-pressurized. Then 750
℃, 400 kgf / cm² Vacuum hot press under the conditions of
Approximately 30% product ratio, diameter 50mm, height 60mm, weight 380g SiC
A scar-reinforced aluminum alloy composite material was prepared. Obtained compound
Tensile strength of composite material: 48kgf / mm² , Young's modulus: 12000kgf
/ mm² ， Hardness: HV250, base metal 6061 alloy
(Tensile strength: 28kgf / mm² , Young's modulus: 7500kgf / mm² ，
Hardness: Strength, Young's modulus, and hardness are higher than HV90)
It was improving. Then, add 20% caustic soda water to this surface.
Alumina fiber with deep etching using solution
To form an exposed part of the base layer with a surface roughness of about 20 μm Rmax.
Formed. Next, 300 mess on this surface with a ball mill.
PbO / SiO crushed to h or less₂-PbO / 2B₂O
₃Is dissolved in water, and a slurry liquid with a suspending agent added is sprayed.
Painted and baked at about 540 ℃ to make a thickness of about 50μm
I got a layer. Next, using the obtained metal composite member,
As in Example 1, the allowable surface pressure, wear reduction and fatigue strength were measured.
Decided The results are shown in Table 1. From the results in Table 1, the allowable surface pressure
Is 700 Mpa and fatigue strength is 175 Mpa (10⁷ Times)
Which is difficult with the conventional aluminum alloy by surface treatment.
Excellent wear resistance and sliding resistance even under high surface pressure
It can be seen that fatigue resistance characteristics are obtained.

Example 3 First, a base layer was manufactured. Base layer is aluminum composite
Material, and pre-formation of ceramic fiber as dispersion strengthening material
A mold (preform) is impregnated with the ADC12 molten alloy.
Immersion method was adopted. Preform is made of colloidal alumina fiber
Kneaded with dull silica and press molding to obtain a fiber volume ratio of about 20.
After adjusting to about 100%, use the one baked at 1000 ° C
I was there. Preheat this preform to a temperature of approximately 400 ° C and
After loading into the mold, pour the molten ADC12 alloy at about 750 ℃.
Immediately 500 kgf / cm² It was impregnated at a pressure of. Got
Composite material has tensile strength: 45kgf / mm² ， Young's modulus: 1100
0kgf / mm² ， Hardness: HV220 and base metal ADC12
(Tensile strength: 30kgf / mm² , Young's modulus: 7500kgf / mm² ，
Hardness: Compared with HV100), it has higher strength, Young's modulus and hardness.
It was improving in each case. Then, dry honey
Applied to form a base layer with a surface roughness of approximately 15 μm Rmax.
I made it. Next, Cr on this surface₂O₃, Al₂O₃, S
iO₂And a ceramic slurry liquid consisting of water,
It was baked at 450 ° C. Then 60% by weight of CrO₃water
The solution was applied to the surface layer and then baked at 450 ° C. This C
rO₃The aqueous solution coating / firing process is defined as one cycle.
After repeating 15 cycles, form a surface layer with a thickness of about 40 μm.
I made it. Next, using the obtained metal composite member,
Measure allowable surface pressure, wear reduction and fatigue strength as in Example 1.
did. The results are shown in Table 1. From the results of Table 1, fiber reinforced
The allowable surface pressure of the Lumi alloy composite material is 850 MPa, and Example 1
High tolerance that is almost equivalent to that of hardened alloy steel
It can be seen that the surface pressure is exhibited. That is, the metal composite of the present invention
The member has excellent wear resistance even under sliding conditions under high surface pressure.
And fatigue resistance characteristics are obtained.

Example 4 The same composite material as in Example 2 was used as the base layer, and a TiO ₂ -based alkoxide solution was applied to the surface of the composite material, which was naturally dried and subsequently heated to about 200 ° C. for hydrolysis. Thus, a TiO ₂ coating film having a thickness of about 20 μm was obtained (sol-gel method). Then, using the obtained metal composite member, the allowable surface pressure, the wear reduction and the fatigue strength were measured in the same manner as in Example 1. As a result, it can be seen that excellent wear resistance and fatigue resistance are obtained as shown in Table 1.

Comparative Examples 1 to 5 For the aluminum alloys shown in Table 1, the allowable surface pressure, wear reduction and fatigue strength were measured in the same manner as in Example 1, and the results are shown in Table 1. From the above results, according to the metal composite member of the present invention, it is possible to obtain extremely excellent wear resistance and fatigue resistance even under a sliding condition at a high surface pressure, which was difficult with the aluminum alloy by the conventional surface treatment. I understand.

In this embodiment, an aluminum alloy is used as the metal forming the base layer, but the same characteristics can be obtained by using magnesium or magnesium alloy, tantalum or tantalum alloy, titanium or titanium alloy. . Similarly, for the ceramics to be impregnated or coated, Cr ₂ O ₃ is used in the present embodiment, but the present invention is not limited to this, and ceramics having similar characteristics such as titanium oxide, silicon oxide, Yttrium oxide, zirconium oxide, aluminum oxide, boron oxide, lead oxide, tin oxide, antimony oxide, titanium nitride, silicon nitride, silicon carbide, tungsten carbide, titanium boride, sialon, enamels, or similar compounds. Is obtained.

[0036]

[Table 1]

[0037]

[Table 2]

[0038]

[Table 3]

[0039]

As described above, according to the present invention, since the metal composite material in which fibers and / or particles are dispersed is used in the base layer, the adhesion between the surface layer and the base layer is improved, Wear resistance and fatigue resistance that can withstand use as a sliding member for high surface pressure can be easily obtained. Therefore, while maintaining the characteristics of the aluminum material that is lightweight and excellent in workability, the characteristics of ceramics such as wear resistance, corrosion resistance, insulation, welding resistance, lubricity, chemical resistance, and weather resistance have been maintained. As it is, it becomes possible to improve wear resistance and fatigue resistance as a sliding member for high surface pressure which requires an allowable surface pressure of at least 600 MPa or more.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a metal composite member of the present invention.

FIG. 2 is a configuration diagram showing an embodiment of a metal composite member of the present invention.

FIG. 3 is a configuration diagram showing an embodiment of a metal composite member of the present invention.

FIG. 4 is a plan view of a test piece used for an abrasion test of an example of the present invention.

FIG. 5 is a side view of a test piece used for an abrasion test of an example of the present invention.

FIG. 6 is a schematic diagram of a wear test method used for evaluation of examples of the present invention.

[Explanation of symbols]

 1 Base layer 2 Dispersion strengthening material 3 Surface layer

Claims (9)

[Claims] 1. A metal composite member comprising a base layer made of a metal composite material in which fibers and / or particles are dispersed, and a surface layer in which the base layer is impregnated with or coated with ceramics. 2. The metal composite member according to claim 1, wherein the surface roughness of the base layer is in the range of 2 to 60 μmRmax. 3. The metal composite member according to claim 1, wherein the base layer has fibers and / or particles protruding from at least a part of the surface thereof. 4. The metal composite member according to claim 1, wherein the base layer has pores on at least a part of the surface thereof. 5. The metal composite member according to claim 1, wherein the volume ratio of the fibers and / or particles dispersed in the metal composite material is in the range of 5 to 35%. 6. The metal composite member according to claim 1, wherein the metal composite material is aluminum or an aluminum alloy system. 7. The metal composite member according to claim 1, wherein the metal composite material is magnesium or a magnesium alloy system, tantalum or a tantalum alloy system, titanium or a titanium alloy system. 8. The metal composite member according to claim 1, wherein the ceramics with which the surface layer is impregnated or coated are titanium oxide, silicon oxide, yttrium oxide, zirconium oxide, aluminum oxide, chromium oxide, boron oxide, Lead oxide, tin oxide, antimony oxide, titanium nitride, silicon nitride, silicon carbide, tungsten carbide,
A metal composite member characterized by being selected from titanium boride, sialon, enamel, or a compound thereof. 9. The metal composite member according to claim 8, wherein the chromium oxide with which the surface layer is impregnated or coated is Cr ₂ O ₃ .