JPS62267435A - Sliding member - Google Patents

Abstract

PURPOSE:To improve the wear resistance, seizure resistance, etc., of both members mentioned below, by forming a sliding member to be combined with a member composed of Al or Mg alloy reinforced with alumina-silica fiber into composite state by the use of a metal coated with thermally sprayed layer of a specific alloy. CONSTITUTION:At least the sliding surface part of the primary member to the secondary member of a sliding member consisting of the primary and the secondary member abutting each other and relatively sliding is constituted of a fiber-reinforced metallic composite material having a composition consisting of, by weight, >=40% Al2O3 and the balance SiO2 and also having 3-30vol% of alumina-silica fiber as fiber reinforcement and Al or Mg alloy as matrix. Moreover, at least the sliding surface of the secondary member to the primary member is constituted of a metal coated with thermally sprayed layer of Fe-C-Cr alloy having a composition consisting of, by weight, 40-70% Cr, 3-9% C, and the balance Fe.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a sliding member consisting of a first member and a second member that come into contact with each other and slide relative to each other. The first member is made of a composite material made of aluminum alloy or magnesium alloy reinforced with alumina-silica fiber, and the second member is made of Fe-C-C.
This invention relates to a sliding member made of metal coated with a sprayed layer of r-alloy.

2. Description of the Related Art In a sliding member made up of two members that come into contact with each other and slide relative to each other, the amount of wear on one or both of those members may be large depending on the combination of the two members.
It can quickly lead to death. In order to deal with this problem, for example, Japanese Patent Laid-Open No. 58-93838 and Japanese Patent Laid-open No. 58-938 filed by the same applicant as the applicant of the present application,
Publication No. 39@ states that one member is made of a 4JAt4 reinforced metal composite material with an aluminum alloy or magnesium alloy as a matrix and an inorganic fiber such as alumina-silica fiber as a reinforcing fiber, and one member is made of a steel of a specified hardness. Attempts have been made to construct the other member and thereby improve the frictional sliding characteristics of the sliding member.

Problems to be Solved by the Invention However, in a sliding member consisting of two members that come into contact with each other and slide relative to each other, if one of the members is made of a fiber-reinforced metal composite material, the other Depending on the material of one member, the wear of the other member may increase, and seizure may occur between these members. Problems such as this may occur.

The present invention provides a sliding member consisting of a first member and a second member that are in contact with each other and slide relative to each other, and the first member is a composite material whose reinforcing fibers are alumina-silica fibers. In the case where the second member is made of metal, various experimental studies have been conducted to find out what characteristics the metal that makes up the second member should have. As a result, it was found that it is preferable to coat the metal with a sprayed layer of a specific alloy.

The present invention is based on the knowledge obtained as a result of various experimental studies conducted by the inventor of the present invention, and is based on the knowledge that r! I
A sliding member consisting of a first member and a second member, the first member being a fiber-reinforced metal composite material in which alumina-silica-based IM fiber is used as a reinforcing fiber and aluminum alloy or magnesium alloy is used as a matrix. The second member is made of a metal coated with a sprayed layer of a specific alloy, and the surrounding member has poor wear resistance and seizure resistance. It is intended to.

Means for Solving the Problems According to the present invention, the above-mentioned object is achieved by providing a sliding member consisting of a first member and a second member that abut each other and slide relative to each other; Ii for at least the second member of one member! i interference part is surface 0wt% or more △120
3. The remaining volume is 4T with a composition of 5if2.
It is made of a fiber-reinforced metal composite material with ~30% alumina-silica fibers as reinforcing fibers and an aluminum alloy or magnesium alloy as a matrix, and at least the sliding surface portion of the second member relative to the first member is 4.
0-70wt%Cr, 3-9w1%C1 balance F
This is achieved by a sliding member made of metal coated with a sprayed layer of Fe-C-Or alloy having a composition of C.

Effects and Effects of the Invention According to the present invention, the sliding surface portion of the first member relative to at least the second member is made of reinforced fibers made of alumina-silica based mM with a volume fraction of 3 to 30%, and a matrix of aluminum alloy or magnesium alloy. The sliding surface portion of the second member relative to at least the first member is made of a fiber-reinforced metal composite material of 40 to 70 wt% Cr, 3 to 9w1
%C, and the remainder is composed of a metal coated with a thermally sprayed layer of Fe-C-0r alloy having a composition of Fe and having excellent surrounding characteristics, so the inventors of the present invention, which will be explained later, As is clear from the results of experimental research, the two components have excellent wear resistance and seizure resistance (the
P can be done.

According to the results of experimental research conducted by the inventor of the present application, Fe-
C-Cr alloy is an alloy suitable for constructing sliding members in combination with the above-mentioned fiber-reinforced metal composite materials, but Cr
If the content exceeds 70 wt%, the amount of high-hardness Cr carbide contained in the sprayed layer becomes excessive, and therefore the hardness of the sprayed layer becomes too high, increasing the amount of wear on the first member.
On the other hand, if the Cr content is less than 5511 t%, especially less than 40 wt%, the amount of C carbides will be small and the wear resistance of the second member will be insufficient.Also, if the Cr content is within the above range In some cases, the C content is less than 5wt%, especially 3w
If it is less than Swt%, it will not be possible to avoid forming Cr carbide, which is necessary to ensure sufficient wear resistance.
In particular, if it exceeds 9 wt%, excessive Cr carbide will precipitate in the base of the sprayed layer, resulting in the molten tA layer becoming harder than necessary, increasing the amount of wear on the first member, and making the solvent layer harder than the base material. It becomes easy to peel off. Therefore, in the present invention, Fe covering at least the sliding surface portion of the second member relative to the first member is used.
-C-C, the composition of the alloy is 40 to 70 wt% Cr13 to
9wt%C, remaining actual cost F13. Preferably 55-7
Qwt%0r15 to 8wt%C, and the remainder is set to Fe based on actual cost.

Also, according to the results of LC experimental research conducted by the inventor of the present application,
If the sliding surface of the second member is made of metal coated with a Fe-C-Cr alloy solvent layer, even if the surface roughness of the sprayed layer is relatively large, the second member The amount of wear of the first and second members can be reduced compared to the case where the members are made of metal that is not coated with the sprayed layer, but if the surface roughness of the sprayed layer is , 2μRz or less, the amount of wear of the two members can be suppressed to a small value of 1. According to another detailed feature of the invention, therefore, the molten u
The surface roughness of J IH is set to 1.2 μRZ or less.

Furthermore, according to the results of experimental research conducted by the inventor of the present application, a part of the alumina-silica-based ta sheet is exposed to the sliding movement due to electrolytic etching of the sliding movement of the first member. When recesses are formed on the surface of the matrix between the alumina and silica-based gA materials, the wear resistance and seizure resistance of the first and second members can be further improved. According to yet another detailed feature of the present invention, the rIJ surface of the first member is electrolytically etched so that a part of the alumina-silica fiber is exposed on the sliding surface; It is used with depressions formed on the surface of the matrix between the alumina and silica tsJIff exposed to the sliding movement.

Furthermore, if the thickness of the sprayed layer of F(!-, -C-Or alloy is too small, the sprayed layer will disappear due to wear and the metal of the second member will be exposed, and conversely, the thickness of the sprayed layer will decrease. If the
e-C-Cr alloy will be used more than necessary,
Sliding members become expensive. Therefore, the thickness of the Fe-c-cr gold alloy sprayed layer is preferably 5 microns or more, particularly 5 to 200 microns, and more preferably 10 to 150 microns.

In one specific embodiment of the invention, the sliding member is an internal combustion engine, the first member is a cylinder liner,
The second member is the piston ring.

In another specific embodiment of the invention, the sliding member is an internal combustion engine, the first member is a piston, and the second member is a piston ring.

Furthermore, alumina as a reinforcing fiber of the composite material of the second member.
When the Δ1203 content of the silica-based fibers, that is, the fibers containing Δ1203 and 3i02 as main components, is less than 40 wt%, the wear resistance of the composite material cannot be sufficiently improved. Therefore, in the present invention, the Al 203 content is 40
wt% or more of alumina-silica fibers are used. The alumina-silica fibers may be either long fibers or short IIH fibers, and have an average fiber diameter of 100μ or less, especially 1 to
The thickness is preferably about 40μ.

Furthermore, if the volume percentage of the alumina-silica fiber is less than 5%, especially less than 3%, the JJI wear resistance of the composite material cannot be sufficiently improved; When the ratio exceeds 15%, especially 30%, the amount of wear of the composite material 1 and the second member increases. Therefore, the volume fraction of the alumina-silica 1111t is set to 3 to 30%, preferably 3 to 15%. Furthermore, the orientation of the alumina-silica fibers may be any orientation such as unidirectional orientation, two-dimensional random orientation, three-dimensional random orientation, etc., but especially in the case of unidirectional orientation and two-dimensional random orientation, sliding movement is difficult. It is preferable to set the angle to be perpendicular to or as close to the unidirectional orientation or the two-dimensional random orientation plane as possible.

Further, the metal constituting the second member may be any metal as long as it can be thermally sprayed with Fe-C-Cr alloy.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention will be explained in detail below by way of example embodiments with reference to the accompanying figures.

Example 1 A speech and behavior member (consisting of two members that touch each other and move relative to each other), one of which is a fiber-reinforced metal composite with alumina-silica fibers as reinforcing fibers and aluminum alloy as a matrix. Abrasion tests and seizure tests were conducted on sliding members made of metal, the other member being made of metal coated with a thermally sprayed layer of Fe-C-Cr alloy. This will be explained in comparison with wear tests and seizure tests conducted on sliding members made of a combination of materials.

First, alumina-silica fibers with an average fiber diameter of 2.8 μm and an average fiber length of 5 mm <55 wt% A11!03, the remainder being substantially s;02) are oriented in a substantially three-dimensional random manner to form a fiber molded body. Yes, category 1! Aluminum alloy (J
A composite material having ISMA grade ΔC8Δ) as a matrix was manufactured. Next, the larger serrations of this composite material are 16X6X.
10nlllll, and one of them (16X6111
A large number of flat test specimens with 111> as the test surface were prepared. For comparison purposes, a large number of flat test specimens were prepared that were made of only an aluminum alloy (LJISl grade ΔC8A) that was not reinforced with alumina-silica fibers and had the same dimensions as the above-mentioned flat test specimens.

Next, these flat test pieces were sequentially set in a friction and wear tester, and a mating member with an outer diameter of 35B, an inner diameter of 3Qmm, and a width of 1
01IIIn spheroidal graphite cast iron LIfS standard FCD70>
, stainless steel rf4 (JIS standard 5US420J 2)
, Fe-C-Cr alloy (631% Qr.

5.5wt%C, 1,2wt%Si, O,Q2wt%
P10.02'#t%S, balance Fe) or cast iron (0,8
The test piece was brought into contact with the end surface of a cylindrical test piece made of stainless steel (JIS standard 5US420J2) coated with a plasma sprayed layer of wt%C, 0.3wt%Si, 0.01wt%P, balance Fe). A wear test was conducted by rotating a cylindrical test piece for 1 hour at a load of 60 kg and a rotational speed of 16 Orpm while supplying lubricating oil (castle motor oil 5W-30>) at a temperature of 150° C. to the contact portion of the test piece.

The combination V of the flat plate test piece and the cylindrical test piece is as shown in Table 1 below. After cleaning one end surface of the cylindrical test piece by shot blasting, the sprayed cast iron layer and cast iron sprayed layer were cleaned using a plasma spraying device (3MB) manufactured by METCO under the conditions shown in &2 and Table 3 below, respectively. In Table 1, the 111th place in the surface roughness of the sprayed layer of the cylindrical test pieces of combinations 11: A to A5 is μRz, and the cylindrical test pieces of other combinations are ) The surface roughness of the test surface of No. 1 was all 1.2 μRZ, and the surface roughness was adjusted by changing the grinding conditions for the test surface.

Table 1 (Part 1) Table 1 (Part 2) Note: 1) Thickness of molten tJ1 50μ, hardness l-('/85
02) Thickness of sprayed layer 50 μ, hardness Hv 500 Table 2 <Plasma spraying conditions for Fe-C-Cr alloy) △r gas flow l: 2200Q, /hrH2 gas flow a: 420
Q/hr Supply current: 450-500△ Average particle size of alloy powder: 40μ Supply amount of alloy powder: 40g/win spraying distance 2m:
100 nin Table 3 (&If iron plasma spraying conditions) Ar gas flow WI: 2200Q/hrH2 gas flow a:
420Q,/hr Supply current: 400-450△ vF Average particle size of iron powder: 40μ Supply fi of cast iron powder: 40g/min Spraying distance:
120m1n The results of this abrasion test are shown in FIG. In addition, in Figure 1,
-F half represents the wear m (wear scar depth μ) of the flat plate specimen, and the lower half represents the wear amount (
Figures 2 to 5 below represent wear reduction throat ac+.
The same goes for the figure.

From Figure 1, it can be seen that the wear values of the flat plate test pieces of combinations A9 to △12 are very high, and especially in the case of combinations All and △omi, the wear amount of the cylindrical test pieces is also relatively high. I understand. In addition, the wear fit of flat plate test pieces of combinations A+ to A8
is a much smaller value than the wear amount of the flat plate test pieces of combinations A9 to A I2, but among these, the combination Δe=A
It can be seen that the wear amount of the cylindrical test piece of s is higher than the combinations A9 and Δ1G, and the wear amount of the cylindrical test piece of combination Al-A3 is smaller than the combination Aa=As.

Thus, in the case of AI''-As, a combination of a flat plate specimen made of an aluminum alloy reinforced with alumina-silica fibers and a cylindrical specimen made of stainless steel coated with a sprayed layer of Fc-C-Cr alloy, , the wear amount of both the flat plate test piece and the cylindrical test piece is smaller than that of other combinations, and in particular, from the wear test results of combinations A1 to A5, the surface roughness of the sprayed layer is 1.2 μRz or less. It turns out that is preferable.

Furthermore, for test piece combinations A+ to Av shown in Table 1 above, lubricating oil at room temperature (castle motor oil 5W-30) was supplied to the contact area between the flat plate test piece and the cylindrical test piece,
While rotating the cylindrical test piece at a rotation speed of 100 Q rpm, the pressing load of the cylindrical test piece against the flat plate test piece was 10 to 9.
The load was increased to 700 kq, and a seizure test was conducted to measure the maximum seizure load.

As a result of this test, combination LAN-As, especially combination △3~
The seizure limit load of △5 is higher than any other combination,
Therefore, it was confirmed that these combinations were also highly resistant to seizure.

Example 2 In the same manner as in Example 1 above, alumina-silica i1M (alumina used in Example 1) was oriented in a substantially three-dimensional random manner at a volume fraction of 8%. (same as silica fiber) is used as reinforcing fiber, magnesium compound & (J
+S standard MC2) as a matrix is high-pressure cast (molten metal temperature 700℃, pressure applied to the molten metal 800℃)
kl'cIg'), and a large number of flat plate test pieces of the same brush cut as in Example 1 were prepared from the composite material.

Next, these flat test pieces were subjected to wear tests and seizure tests using the test piece combinations shown in Table 4 below in the same manner and under the same conditions as in Example 1. The cylindrical test pieces of combinations B+ to B4 shown in Table 4 below were thermally sprayed with Fe-c-Cr alloy in the same manner and under the same conditions as combinations A+ to △4 shown in Table 1 of -L. A layer was formed and the surface roughness was adjusted, and the surface roughness of the test surface of the cylindrical test piece of combination B5 was 1.2 μRz.

Table 4 The results of this wear test are shown in Figure 2. From Fig. 2, compared to the case of combination tr135, the wear amount of combinations 81 to B4 is lower in terms of cracking of the flat plate test piece and the cylindrical test piece, and in particular, the wear of combinations 83 and 84 is lower than that of the flat plate test. lower than that of combinations B1 and B2 for both the blank and cylindrical specimens (1α), therefore the alumina-silica u1
All combinations of composite material made of navy blue reinforced magnesium alloy and stainless steel coated with a sprayed layer of Fe-C-Cr alloy have excellent wear resistance.
It can be seen that the surface roughness of the thermally sprayed C-Cr alloy layer is preferably 1.2 μRZ or less.

Also, although not shown in the figure, as a result of seizure tests, composite materials made of magnesium alloy reinforced with alumina-silica fibers were compared with stainless steel coated with a sprayed layer of Fe-C-Cr alloy. It was confirmed that the combination also has excellent seizure resistance.

Example 3 In the same manner as in Example 1 above, alumina fibers (95 wt% Al 203, the remainder substantially S!Oz, A composite material with an average fiber N diameter of 3.2μ and an average fiber length of 8ml11) as reinforcing fibers and an aluminum alloy (JIS standard ADC10) as a matrix was high-pressure cast (molten metal temperature 74mm).
At 0°C, the pressure applied to the molten metal is 500 k (1/cm2
), and a large number of flat test specimens with the same dimensions as in Example 1 were prepared from the composite material.

Next, a wear test and a seizure test were conducted on these flat test pieces in the same manner and under the same conditions as in Example 1 using the combinations of test pieces shown in Table 5 below. The cylindrical test pieces of the combinations LC+ to C4 shown in Table 5 below were each coated with a thermally sprayed layer of Fe-C-Cr alloy in the same manner and under the same conditions as the combinations ΔXia to A4 shown in Table 1 above. was formed and the surface roughness was adjusted, and the surface roughness of the test surface of the cylindrical test piece of combination C5 was 1.2 μRZ.

Table 5 The results of this wear test are shown in Figure 3. From FIG. 3, compared to the case of combination C5, the wear m of combinations C+ to C4 is a lower value for both the flat plate test piece and the cylindrical test piece.
In particular, the wear amounts of combinations C3 and C4 are lower than those of combinations C1 and C2 for both flat plate and cylindrical specimens, and therefore, the composite material made of an aluminum alloy reinforced with alumina fibers and Fe- The combination with stainless steel coated with molten Q'1 layer of C-Cr alloy also has excellent wear resistance, and Fe-c-cr gold alloy? 8
It can be seen that the surface roughness of the shot is preferably 1.2 μRZ or less.

Although not shown in the figure, as a result of the seizure test, the combination of a composite material made of aluminum alloy reinforced with alumina Jll and stainless steel coated with a sprayed layer of Fe-C-Cr alloy was It was also confirmed that it has excellent seizure resistance.

Example 4 Using the same formula as in Example 1 above, alumina fibers oriented in a substantially three-dimensional random manner at a volume fraction of 6% (same as the alumina fibers used in Example 3) Same) as reinforcing fiber, magnesium alloy (JIS standard +8MC2)
A composite material with a matrix of
), and a large number of flat test specimens with the same dimensions as in Example 1 were prepared from the composite material.

Then, for these flat test specimens, Table 61 below:
A wear test and a seizure test were conducted using the combination of test pieces shown in the same manner and under the same conditions as in Example 1. The cylindrical test pieces of the combinations (1 to D4) shown in Table 6 below were tested under the same shell area and conditions as the combinations A+ to △4 shown in Table 1 above [: (!-〇 - One layer of melted Cr alloy is formed and the surface roughness is: A, and the surface roughness of the tested surface of the cylindrical test piece of combination D5 is 1.2 μRZ.
Met.

Figure 4 shows the results of the wear test shown in Table 4. From FIG. 4, it can be seen that the combinations D+ to D4 are 1? compared to the case of combination D5. The wear and tear value is low for both the flat plate test piece and the cylindrical test piece.
Especially 1 of combinations D3 and D4? The abrasion Iβ is lower than the combinations D+ and D2 for both the flat plate test piece and the cylindrical test piece. It can be seen that the combination with the stainless steel coated with the Fe-c-cr gold alloy is also highly wear resistant, and the surface roughness of the Fe-c-cr gold alloy molten OA layer is preferably 1.2 μRZ or less.

Although not shown in the figure, as a result of seizure tests, the combination of a composite material made of magnesium alloy reinforced with alumina fibers and stainless steel coated with a sprayed layer of Fe-C-Cr alloy was It was also confirmed that it has excellent seizure resistance.

Example 5 7. Used in Example 1. - The same alumina-silica fibers as the thick aluminum fibers are oriented in a substantially three-dimensional random manner to form a TG fiber molded body, and the high-pressure casting (of molten metal) U is performed using the fiber molded body. At a temperature of 730°C and a pressure of 500 kg/cm9) on the molten metal, the volume ratio is 8.
% of alumina-silica fiber as a reinforcing fiber and an aluminum alloy (JIS standard △DT4) as a matrix was priced at ¥1. Then, from this composite material, the outer diameter is 25
．． C1dll, inner diameter 20.0mm, length 16111I
Five cylindrical test pieces having a dimension of 11 mm and one end face as the test surface were formed, and the surface roughness of the test surface of each test piece was finished to 0.6 μRz by grinding.

Next, recesses were formed on the surface of the matrix of the test surface of the three cylindrical test pieces by electrolytic etching using an If aqueous solution. FIG. 5 is a schematic diagram showing a cross section of the thus formed test piece near the surface to be tested.
1 indicates alumina-silica fibers as reinforcing fibers, 22 indicates an aluminum alloy as a matrix, and 23 indicates a recess.

In this case, by appropriately setting the electrolytic etching strip ft, the average depth Dj of the depth Di of the recess 23 appearing in an arbitrary cross section of the test surface is 1.8μ, and the depth of the recess 23 with respect to the frontage i 1f4, that is, the average value Di/' of the ratio of the depth Qi to the opening length Wi of the recess 23 appearing in any cross section of the surface to be tested, IV i is 0.
02, the exposed height of the alumina-silica fibers from the surface 24 of the composite material (the average (direction H1) of 1 is 0.8 μ, and the area ratio of the recesses, that is, the Three cylindrical test pieces were formed in which the ratio of the total opening length Wl of the recess 23 to the reference length [-] was 20%.

Next, these cylindrical test pieces were subjected to electrolytic etching, and cylindrical test pieces made of a composite material that were not electrolytically etched and had the depth of the recess, the exposed height of the alumina-silica fiber, and the area ratio of the recess were O. Sequentially set in a friction and wear tester, stainless steel (JIS standard 5US420J2
>, the size is 30 x 30 x 5 mm, and one of the pieces (30 x 30111 Il) is brought into contact with the test surface of a flat plate test piece, and the contact part of these test pieces is coated with room temperature lubricating oil ( Ki-Tsuru motor oil 5AE3
0) and rotating the cylindrical test piece at a rotational speed of 1100 orp, the suppressing load of the cylindrical test piece against the flat plate test piece was increased from 10 kg to 800 ko, thereby measuring the seizure limit load. I did it.

The combinations of cylindrical test pieces and flat plate test pieces in this seizure test were as shown in Table 7 below.

In addition, the surface roughness of the tested surface of each flat test piece was 1°2μ.
Rz, and the sprayed layers of Fe-C-Cr alloy on the flat plate test pieces of combinations E+, E4, and E5 were plasma sprayed under the same conditions as shown in Table 2) Table 3, respectively. was formed by.

Table 7 The results of this seizure test are shown in Figure 6. From Fig. 6, the seizure limit load of combination [E+ is much higher than the seizure limit load of combination tr E 2, and the seizure limit of combination E4 7Jj8I''! is the seizure limit of combinations E2, E3, and E5. much higher than the load and therefore alumina-silica I
Melting of composite material made of aluminum alloy reinforced with H and Fe-C-Or alloy +2. A combination of stainless steel coated with a layer of electrolytically etched composite material made of aluminum alloy reinforced with alumina-silica fibers and stainless steel coated with a sprayed layer of Fe-C-Cr alloy. It can be seen that the combination has poor seizure resistance. Also especially union t! [From a comparison between 1 and E4, it can be seen that if the composite material is subjected to electrolytic etching to expose the reinforced II film and to form recesses between the reinforcing fibers on the surface of the composite material, the seizure resistance will be significantly improved. .

Although not shown in the plan view, the yL of Example 1 and 1iil- for the combinations of test pieces shown in Table 7
When a wear test was conducted in the territory, it was found that the combinations L'E1 and E4
．． In particular, combination E4 was confirmed to have excellent wear resistance.

Embodiment 6 Figure 7 shows internal combustion (1 leap piston and piston ring)
An exploded vertical cross-sectional view showing a specific embodiment of the opening member according to the present invention, which is made up of a single assembly, FIG. FIG. 3 is an enlarged partial vertical cross-sectional view of the top ring.

In these figures, 1 is a piston, and aluminum 1
1 alloy (JIS standard 8C △). The side outer circumferential surface 2 of the piston 1 has two compression rings 4 and 5 for receiving compression rings 4 and 5 that prevent combustion gas from leaking from the combustion chamber of the internal combustion engine between the piston 1 and the cylinder wall surface of the cylinder block 3. two ring grooves 6 and 7;
A ring groove 9 is formed to receive an oil ring 8 that scrapes off excess oil.

In the water metering embodiment, one side 1 of the top ring groove 6 is placed from the piston head 10 along the side outer circumferential surface 2 of the piston 1.
The lower part of 1 (U) in which the same alumina-silica fibers as the alumina-silica fibers used in Example 1 were oriented three-dimensionally randomly at a volume fraction of 8% in a real τ1 manner.
& Miscellaneous compacts are used as reinforcing materials, and other parts of the screws 1 to 1 are made of a composite material 12 made of an aluminum alloy (JIS standard 8C △) with 7 trixes.This composite material 12 defines the wall surface of the top ring groove 6 that receives the top ring 4, and also defines a part of the top land 13 and the cant land 14 in the part exposed on the side outer peripheral surface 2 of the piston. .

In addition, the fiber molded body is placed on the bottom wall of the mold cavity of the mold for casting the screw, and the molten aluminum alloy is poured into the mold, and the mold is sealed in a liquid-tight manner. The aluminum alloy is pressurized by a fitting plunger and solidified to form a rough piston material, which is then heat treated (6-6 treatment) and then processed to a predetermined size, and furthermore, by forming a ring groove 6.7. May be built.

The top ring 4, which contacts the piston 1 as described above and slides relative to it, is made of stainless steel (J■S standard r6SU
S420J 2)1. Although not shown in the figure, the lower surface 17 is made of FQ-C-Cr alloy with a thickness of 20 μm formed by plasma solvent. It is coated with a 8-iron coating (same composition as the sprayed layer of Fe-c-Cr alloy in Example 1, surface roughness 0.8 μRz). In particular, the illustrated embodiment is configured as a 7° keystone ring, and a molybdenum 15 is formed on the sliding surface of the cylinder tab 3 with the cylinder wall surface.

The piston and piston ring configured as described above are
Built into a cylinder 4-stroke diesel engine, the engine speed is 5.
5 at test condition R1 of 400 rpm and full engine load.
A durability test was conducted for 00 hours. For the purpose of comparison, a durability test was also conducted under the same conditions for a piston ring made of spherical graphite VFI iron (JIS standard FCD70) whose lower surface 17 was not coated with a sprayed layer of Fe-C-Cr alloy. went.

As a result of the test, in the case of a piston ring made of spheroidal graphite cast iron, the wear value of the lower surface 11 of the ring groove was 20μ, and the wear amount of the lower surface 17 of the piston ring was 15μ, whereas the lower surface 17 was made of Fe. - In the case of a piston ring coated with a sprayed layer of C-Cr alloy, the lower surface 11 of the ring groove
The wear value of the piston ring was 5μ, and the wear amount of the lower surface 17 of the piston ring was 0°8μ. Therefore, it was recognized that the piston and piston ring of the example had much better wear resistance than the comparative example. .

Example 7 The alumina-silica fibers and aluminum alloy used in Example 1 above were reinforced with 10% volume fraction alumina-silica fibers oriented in a substantially three-dimensional random manner. By manufacturing a cylinder liner made of aluminum alloy by high-pressure casting (temperature of molten metal 730°C, pressure applied to the molten metal 500 ka/cw+9), and enclosing the cylinder liner by gravity casting,
A cylinder block for a four-cylinder, four-cycle internal combustion engine with a cylinder bore diameter of 80IllI11 was formed twice, and the cylinder bore of each cylinder block was finished to a surface roughness of 0.6 μRz by honing.

Next, it is made of stainless steel LJIS standard 5US420J2), and the outer peripheral surface on the outside in the half-rod direction is coated with one layer (actual MTf) of Fe-C-Cr alloy with a thickness of 150μ by plasma spraying.
A piston ring coated with the same composition as the sprayed layer of Fe-C-Cr alloy of A1 and a surface roughness of 1.2 μRz),
Made of spheroidal graphite cast iron (JIS standard FCD70) Fe-
Piston rings as a comparative example which were not coated with a sprayed layer of c-Cr alloy were prepared, and these piston rings and the cylinder block described above were assembled into a 4-cylinder 4-stroke diesel engine, and the engine was assembled. Rotation @6000rpa
+, A high-speed durability test was conducted for 200 hours under full engine load.

As a result of this test, when the piston ring was made of spheroidal graphite cast iron, scuffing occurred in the cylinder bore and the wear amount of the cylinder bore was as high as 18μ, whereas when the piston ring was made of Fe-C -Cr
In the case of piston rings made of stainless steel coated with a thermally sprayed layer of alloy, no scuffing occurred in the cylinder bore, and the amount of wear on the outer peripheral surface of the piston ring and cylinder bore was extremely low, with the amount of wear being less than 2μ. Therefore, the cylinder liner and piston ring of the example are generally superior in corrosion resistance compared to the comparative example.
I got hit twice.

Although the present invention has been described in detail with reference to several embodiments above, the present invention is not limited to these embodiments, and various other embodiments are possible within the scope of the present invention. It would be obvious to anyone skilled in the art that this is the case.

[Brief explanation of drawings]

FIGS. 1 to 4 are graphs showing the results of the abrasion tests for Examples 1 to 4, respectively, and FIG. A schematic diagram showing a cross section of the surface part of the material, FIG. 6 is a graph showing the results of the seizure test of Example 5, and FIG. 7 is a sliding member according to the present invention applied to a combination of a piston and a piston ring. An exploded vertical cross-sectional view showing one specific example of the
FIG. 9 is an exploded enlarged partial vertical sectional view showing the main parts of the embodiment shown in the figure, and FIG. 9 is a previous partial longitudinal sectional view showing an enlarged piston ring (top ring). 1... Piston, 2... Side outer peripheral surface, 3... Cylinder liner, 4... Top ring, 5... Second ring. 6...Top ring groove, 7...Second ring) 10, 8...Oil ring, 9...Ring M, 10...
・Piston head, 11... 1 ~ Lower surface of tubing groove, 12... Composite material, 13... Top land, 14
...Second land, 15...Molybdenum solution 1j1
．． 17... Lower surface of top ring, 21... Alumina-silica fiber, 22... Aluminum alloy, 23...
・Concave portion, 24...Surface portion Applicant: Toyota Automotive Co., Ltd. Representative: Patent Attorney Masaki Akashi

Claims (6)

[Claims] (1) A sliding member consisting of a first member and a second member that are in contact with each other and slide relative to each other, and the sliding surface portion of at least the first member relative to the second member is 40W.
It is composed of a fiber-reinforced metal composite material having a volume ratio of 3 to 30% alumina-silica fibers having a composition of t% or more Al_2O_3 and the remainder substantially SiO_2 as reinforcing fibers and an aluminum alloy or magnesium alloy as a matrix. The sliding surface portion of the second member relative to at least the first member is 40 to 70 wt% Cr and 3 to 9 wt%
%C, the balance being essentially Fe-C-C
A sliding member made of metal coated with a sprayed layer of r-alloy. (2) In the sliding member according to claim 1, the composition of the Fe-C-Cr alloy is 55 to 70 wt% Cr, 5
A sliding member characterized in that C is ~8wt%, and the balance is Fe in actual cost. (3) The sliding member according to claim 1 or 2, wherein the plating layer has a surface roughness of 1.2 μRz or less. (4) In the sliding member according to any one of claims 1 to 3, the sliding surface of the first member is electrolytically etched so that a portion of the alumina-silica fiber is removed. is exposed on the sliding surface, and a recess is formed on the surface of the matrix between the alumina-silica fibers exposed on the sliding surface. (5) In the sliding member according to any one of claims 1 to 4, the sliding member is an internal combustion engine, the first member is a cylinder liner, and the second member is a cylinder liner. A sliding member characterized in that the member is a piston ring. (6) In the sliding member according to any one of claims 1 to 4, the sliding member is an internal combustion engine, the first member is a piston, and the second member is a piston. is a sliding member characterized by being a piston ring.