JP2001049404A - Piston ring wear resistant ring made of free graphite precipitated iron base sintered alloy excellent in high temperature wear resistance and thermal conductivity - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piston ring wear resistant ring made of a free graphite precipitated iron base sintered alloy excellent in high temp. wear resistance and thermal conductivity and small in attackability to the other material. SOLUTION: This wear resistant ring has a compsn. contg., by weight, 11 to 40% Cu, 0.5 to 10% Ni and 0.8 to 3% C and furthermore contg., at need, 0.1 to 15% Mo and/or 0.1 to 10% Cr, and the balance Fe with inevitable impurities and a structure in which a free graphite phase is precipitately dispersed into a base obtd. by coupling an Fe base alloy phase consisting essentially of Fe with a Cu base alloy phase consisting essentially of Cu.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piston ring wear ring made of a free graphite-precipitated iron-base sintered gold having excellent high-temperature wear resistance and thermal conductivity and low aggressiveness (piston ring aggressiveness). Things.

[0002]

2. Description of the Related Art Conventionally, as shown in a schematic vertical sectional view of FIG. 2 (a), a piston of a diesel engine for trucks and buses has a piston ring wear ring cast immediately below a top land portion at the time of casting a piston casting body. The piston ring is mounted by wrapping, and thereafter, the outer circumference of the piston ring wear ring is cut to form a top ring groove having a U-shaped cross section on the outer circumference of the piston ring wear ring. It is known to manufacture by fitting as shown in a main part longitudinal sectional view of FIG. Further, the piston casting main body is mainly composed of A containing 8 to 13% by weight of Si.
The piston ring wear ring is made of an l-Si alloy and is made of Fe-Ni having good wear resistance and low aggressiveness.
-Cu-based sintered material (composition: Fe-8 to 25% Ni-3.
5-10% Cu-2.0% or less C), Ni-Cu-C
Ni-resist cast iron, which is an r-based austenitic cast iron (composition:
Fe-13 to 16% Ni-5 to 8% Cu-1.5 to 2.
4% Cr-1.4-1.8% Si-0.5-1.2% M
n-2.5 to 3% C, more than% by weight, and less than% indicates% by weight).

[0003]

On the other hand, exhaust gas regulations for automobiles tend to be stricter year by year, and at the same time, there is still a demand for improvement in fuel economy. A direct-injection engine that directly injects fuel into a room and a lean-burn engine that performs lean combustion by increasing the air-fuel ratio have been developed. In these new engines, the combustion chamber becomes hotter than the conventional engine, and the piston ring wear ring is also affected by the high-temperature combustion chamber, so the piston made of the conventional Fe-Ni-Cu sintered material or Niresist cast iron Rapid wear progress is inevitable in ring bearing rings.

[0004]

Means for Solving the Problems Accordingly, the present inventors have
From the above viewpoints, we conducted research to develop a piston ring wear ring for a piston that can be incorporated into a direct injection engine or a lean burn engine.
Cu: 11 to 40%, Ni: 0.5 to 10%, C:
0.8 to 3%, with the balance being Fe and unavoidable impurities, and the Fe-based alloy phase mainly composed of Fe
A piston ring wear ring composed of an iron-based sintered alloy having a structure in which precipitated free graphite is dispersed in a matrix formed by a Cu-based alloy phase containing u as a main component has a (a) component composition of Cu (B) Fe-based alloy phase containing Fe as a main component is mainly composed of Cu because of its excellent thermal conductivity, improved heat dissipation and reduced temperature rise, and thus improved high-temperature wear resistance. It has a structure formed by bonding with a Cu-based alloy phase as a component, an Fe-based alloy phase containing Fe as a main component is a hard phase, a Cu-based alloy phase containing Cu as a main component is a soft phase, and (C) Since it is composed of a mixed structure of a soft phase and a soft phase, it has excellent wear resistance and low aggressiveness, and has excellent adhesion to the Al-Si alloy constituting the piston body. The Fe-based alloy phase mainly composed of Fe is C The research results show that the structure formed by bonding with a Cu-based alloy phase containing as a main component is low in the aggressiveness of the partner, but free graphite is further precipitated in the base material, so that the aggressiveness of the partner is further reduced. .

The present invention has been made on the basis of the above research results, and (1) Cu: 11 to 4% by weight.
0%, Ni: 0.5 to 10%, C: 0.8 to 3%, the balance being Fe and unavoidable impurities, and Fe-based alloy phase mainly composed of Fe being mainly composed of Cu. Free graphite precipitated iron-based sintering composed of an iron-based sintered alloy having a structure in which precipitated free graphite is dispersed in a matrix formed by a Cu-based alloy phase and having excellent high-temperature wear resistance and thermal conductivity It is characterized by an alloy piston ring wear ring.

The structure of the piston ring made of free graphite-precipitated iron-bonded gold according to the present invention will be described with reference to FIG.
FIG. 1 shows an example of the metallographic structure of a piston ring made of free graphite-precipitated iron-bonded gold according to the present invention. In FIG. 1, 1
Is a Fe-based alloy phase mainly composed of Fe, 2 is a Cu-based alloy phase mainly composed of Cu, and 3 is precipitated free graphite. As is clear from the metallographic diagram in FIG. 1, the structure of the piston ring wear ring made of free graphite-precipitated iron-base bonded gold according to the present invention has a Fe-based alloy phase 1 containing Fe as a main component and a Cu-containing component containing Cu as a main component.
It can be seen that the base has a base combined with the base alloy phase, and fine precipitated free graphite is dispersed in the base.

[0007] The content of the Fe-based alloy phase and the Cu-based alloy phase constituting the structure of the piston ring made of free graphite-precipitated iron-base sintered gold of the present invention can be determined by EPMA. As a result of measurement by EPMA, the Fe-based alloy phase 1 shown in FIG. 1 contains Ni, Cu, and C and Fe at 50% by weight or more, and the Cu-based alloy phase 2 contains Ni, Fe, and C, and contains Cu. It was found that the concentration of Ni and C contained in the Fe-based alloy phase was higher than the concentrations of Ni and C contained in the Cu-based alloy phase.

Accordingly, the present invention relates to (2)
And Cu: 11 to 40%, Ni: 0.5 to 10%, C
: A composition containing 0.8 to 3%, with the balance being Fe and unavoidable impurities, and a substrate formed by combining an Fe-based alloy phase mainly containing Fe with a Cu-based alloy phase mainly containing Cu. The Fe-based alloy phase having Fe as a main component is a Fe-based alloy phase containing Ni, Cu and C and containing 50% or more of Fe, and the Cu Cu-based alloy phase mainly composed of Ni, Fe
And a C-based alloy phase containing 50% or more of Cu, wherein the concentration of Ni and C contained in the Fe-based alloy phase is higher than the concentration of Ni and C contained in the Cu-based alloy phase. It is characterized by a piston ring made of free graphite-precipitated iron-base sintered gold having excellent wear resistance and heat conductivity.

According to the present invention, an iron-based sintered alloy having the composition described in the above (1) or (2) is further provided with a Mo: 0.1 to
More preferably, one or two of 15% and Cr: 0.1 to 10% are contained. Both Mo and Cr are dissolved in the Fe-based alloy phase and the Cu-based alloy phase. And the amount of solid solution of Cr is higher in the Fe-based alloy phase than in the Fe-based alloy phase.
More than the base alloy phase. Therefore, the present invention provides (3)
In weight%, Cu: 11 to 40%, Ni: 0.5 to 10
%, C: 0.8 to 3%, Cr: 0.1 to 10%, the balance being Fe and inevitable impurities, and F
e-based Fe-based alloy phase to Cu-based
Made of free graphite-precipitated iron-base sintered gold with excellent high-temperature wear resistance and thermal conductivity composed of an iron-based sintered alloy having a structure in which precipitated free graphite is dispersed in a matrix formed by a u-based alloy phase (4) The Fe-based alloy phase containing Fe as a main component is a Fe-based alloy phase containing Ni, Cu, Cr, and C, and containing 50% or more of Fe. The Cu-based alloy phase is composed of Ni, Fe, C
is a Cu-based alloy phase containing r and C and containing 50% or more of Cu, and the concentration of Ni, Cr and C contained in the Fe-based alloy phase is set to the concentration of Ni, Cr contained in the Cu-based alloy phase.
(3) a graphite ring made of iron-based sintered iron-free bonded graphite having excellent high-temperature abrasion resistance and heat conductivity as described in (3) above, which is larger than the concentration of C and C;
1 to 40%, Ni: 0.5 to 10%, C: 0.8 to 3
%, Mo: 0.1 to 15%, the balance being Fe and inevitable impurities, and Fe containing Fe as a main component.
High-temperature wear resistance and thermal conductivity composed of an iron-based sintered alloy having a structure in which precipitated free graphite is dispersed in a matrix formed by combining a base alloy phase with a Cu-based alloy phase containing Cu as a main component Excellent free graphite-precipitated iron-base sintered gold-made piston ring wear ring. (6) The Fe-based alloy phase containing Ni as the main component contains Ni, Cu, Mo and C, and contains 50% of Fe.
The above-mentioned Fe-based alloy phase, wherein the Cu-based alloy phase containing Cu as a main component is a Cu-based alloy phase containing Ni, Fe, Mo, and C and containing 50% or more of Cu. The concentration of Ni, Mo and C contained in
(7) The piston ring wear ring made of iron-based sintered iron-free bonded graphite having excellent high-temperature wear resistance and heat conductivity according to the above (5), which is larger than the concentrations of Ni, Mo and C contained in the u-based alloy phase. % By weight, Cu: 11 to 40%, Ni:
0.5 to 10%, C: 0.8 to 3%, Mo: 0.1 to
15%, Cr: 0.1 to 10%, the balance being Fe and unavoidable impurities, and a Fe-based alloy phase mainly composed of Fe combined with a Cu-based alloy phase mainly composed of Cu. (8) a piston ring made of an iron-based sintered alloy made of an iron-based sintered alloy having excellent high-temperature wear resistance and heat conductivity, which is composed of an iron-based sintered alloy having a structure in which precipitated free graphite is dispersed in a base material; ) The Fe-based alloy phase containing Fe as a main component contains Ni, Cu, Mo, Cr and C, and
e is a Fe-based alloy phase containing 50% or more of e, and the Cu-based alloy phase containing Cu as a main component is a Cu-based alloy phase containing Ni, Fe, Mo, Cr and C, and containing 50% or more of Cu. , The concentration of Ni, Mo, Cr and C contained in the Fe-based alloy phase is determined by the concentration of Ni, M contained in the Cu-based alloy phase.
A piston ring wear ring made of an iron-based sintered gold-free bonded graphite having excellent high-temperature abrasion resistance and heat conductivity as described in (7) above, which is larger than the concentrations of o, Cr and C.

[0010] The piston ring bearing ring made of iron-based sintered gold free of graphite having excellent high-temperature wear resistance and thermal conductivity according to the present invention containing Mo: 0.1 to 15% has a Mo content of 15 as a raw material powder. % Of Fe-Mo alloy powder, the hard particles containing Mo as a main component are not formed in the base material, but the Mo content is 15% as the raw material powder.
% Of Fe-Mo alloy powder,
A structure in which hard particles containing Mo as a main component containing 50% or more of Mo are formed and dispersed in the matrix is obtained, and the wear resistance of the piston ring wear ring having this structure is particularly improved.

Therefore, the present invention provides (9)
And Cu: 11 to 40%, Ni: 0.5 to 10%, C
: 0.8 to 3%, Mo: 0.1 to 15%, the balance being Fe and unavoidable impurities, and a Fe-based alloy phase containing Fe as a main component and a Cu-base containing Cu as a main component. Precipitated free graphite and M deposited in a matrix combined by an alloy phase
a piston ring made of iron-based sintered gold-free bonded iron-based sintered ring having excellent high-temperature wear resistance and thermal conductivity composed of an iron-based sintered alloy having a structure in which hard particles containing o as a main component are dispersed; ) The Fe-based alloy phase containing Fe as a main component,
A Fe-based alloy phase containing Ni, Cu, Mo and C and containing 50% or more of Fe, and
The base alloy phase contains Ni, Fe, Mo and C and contains Cu
And the concentration of Ni, Mo and C contained in the Fe-based alloy phase is higher than the concentration of Ni, Mo and C contained in the Cu-based alloy phase. ) Described above, a free graphite-precipitated iron-base sintered gold piston ring wear ring having excellent high-temperature wear resistance and heat conductivity, (11)% by weight, Cu: 11 to 40%, Ni: 0.
5-10%, C: 0.8-3%, Mo: 0.1-15
%, Cr: 0.1 to 10%, the balance being Fe and inevitable impurities, and Fe containing Fe as a main component.
The base alloy phase was composed of an iron-based sintered alloy having a structure in which precipitated free graphite and hard particles containing Mo as a main component were dispersed in a matrix formed by bonding with a Cu-base alloy phase containing Cu as a main component. Piston ring wear ring made of free graphite-precipitated bonded iron with excellent high-temperature wear resistance and thermal conductivity. (12) The Fe-based alloy phase containing Fe as a main component is Ni, Cu, M
Fe containing o, Cr and C and containing 50% or more of Fe
A Cu-based alloy phase containing Ni, Fe, Mo, Cr and C as a main alloy phase, and a Cu-based alloy phase containing 50% or more of Cu. The concentration of Ni, Mo, Cr and C contained is
The piston ring wear ring made of an iron-base sintered gold-free bonded graphite having excellent high-temperature wear resistance and heat conductivity according to the above (11), which is higher than the concentrations of Ni, Mo, Cr and C contained in the u-base alloy phase. It has features.

The method for producing the piston ring wear ring made of free graphite-precipitated iron-bonded gold according to the present invention described in the above (1) or (2) will be specifically described. As the raw material powder, Fe powder, graphite powder and Cu- Prepare a Ni alloy powder, mix these raw material powder with zinc stearate powder or ethylene bis stearamide which is a lubricant at the time of mold molding with a double cone mixer, press mold to produce a green compact, Body in nitrogen atmosphere containing hydrogen, temperature: 1100
Sinter at １1300 ° C. Sintering temperature is 1100-120
0 ° C. is more preferred.

Further, in order to produce the piston ring wear ring made of free graphite-precipitated bonded iron according to any one of the above (3) to (10), Fe powder, graphite powder and Cu- In addition to the Ni alloy powder, an Fe-Cr alloy powder and an Fe-Mo alloy powder are prepared, and a predetermined amount of these raw material powders is blended and mixed. Further, zinc stearate powder or ethylene bis The mixture is mixed with stearamide by a double cone mixer and press-molded to produce a green compact, and the green compact is sintered in a nitrogen atmosphere containing hydrogen at a temperature of 1100 to 1300 ° C. The sintering temperature is more preferably 1100 to 1200 ° C.

Among the iron-based sintered alloys containing Mo, the iron-based sintered alloy according to the above (9) to (12), which has a structure in which hard particles mainly containing Mo are dispersed in a base material, (5) to (8), which are manufactured by adding an Fe-Mo alloy powder having a Mo content of more than 15%, and having a structure in which hard particles containing Mo as a main component are not dispersed in the base material. In order to manufacture the iron-based sintered alloy, an Fe-Mo alloy powder having a Mo content of 15% or less is added.

The mechanism for sintering the piston ring wear ring made of free graphite-precipitated bonded iron according to the above (1) and (2) of the present invention is considered to be as follows. That is, the graphite powder added as a raw material once forms a solid solution in the base material by sintering, becomes extremely fine free graphite during cooling after sintering, and is precipitated and dispersed in old pores. On the other hand, when the temperature is raised to the solid solution coexistence region of the Cu-Ni alloy in the initial stage of sintering, Ni of the Cu-Ni alloy powder starts to diffuse into the Fe powder, thereby improving the adhesion between the Fe phase and the Cu phase. In the middle stage of sintering, the diffusion amount from Cu-Ni to Fe increases,
The amount of liquid phase generation also increases gradually. N in the later stage of sintering
Most of i is diffused into Fe powder, so Cu-N
The melting point of the i-alloy powder decreases due to a decrease in the Ni content, and the Cu-Ni alloy powder melts at a stretch, and dynamic liquid phase sintering proceeds to make the powder denser. After a liquid phase is gradually generated in the early and middle stages of sintering, a large amount of the liquid phase is generated only in the latter period, so that no bending or distortion occurs. The sintering of the present invention is considered to be based on the mechanism described above. Therefore, as a raw material powder used for producing the piston ring wear ring made of free graphite-precipitated iron-based sintered gold of the present invention, particularly, a Cu-Ni alloy ( It is desirable to use a mother alloy) powder containing 2 to 30% by weight of Ni and the balance of Cu and inevitable impurities. (1) or (2) above
The mechanism for sintering the piston ring bearing ring made of free graphite-precipitated iron-based sintered gold described above has been described in detail, but the free graphite-precipitated iron-based sintered binder according to any one of the above (3) to (12) has been described. It is considered that the mechanism at the time of sintering the piston ring made of ring is almost the same.

Next, the reason why the component composition of the free graphite-precipitated iron-based sintered metal constituting the piston ring wear ring of the present invention is limited as described above will be described.

(A) Cu Cu has improved heat dissipation, aggressiveness to a partner and abrasion resistance.
Further, it has the effect of improving the adhesion to the piston body, but if the content is less than 11% by weight, the desired effect cannot be obtained, while if it exceeds 40% by weight, the liquid phase becomes excessive,
It is not preferable because deformation occurs during sintering and dimensional variation increases. Therefore, the content of Cu is 11 to 40.
% By weight. A more preferable range of the Cu content is 1
2 to 25% by weight.

(B) Ni Ni increases the melting point of the Cu alloy phase in the Cu alloy phase, controls liquid phase sintering,
It has the effect of improving the adhesion to the u-alloy phase, but if its content is less than 0.5% by weight, its effect is not sufficient, while if its content exceeds 10% by weight, its effect is no more. Few. Therefore, the content of Ni is 0.5 to 10% by weight.
Determined. A more preferred range of the Ni content is 1 to 8% by weight.

(C) C C has the effect of improving strength and hardness, but if its content is less than 0.8% by weight, free graphite does not precipitate in the base material, so that it is sufficient to reduce the aggressiveness to the partner. But, on the other hand,
It is not preferable because the toughness contained exceeding 3.0% by weight is lowered. Therefore, the content of C is 0.8 to 3.0.
% By weight. The more preferable range of the content of C is 1.
1 to 2.0% by weight.

(D) Cr The Cr component forms a solid solution in the austenite phase base material, improves its heat resistance, and thus has the effect of improving the high-temperature wear resistance of the piston ring wear ring. However, if the content is less than 0.1%, a desired improvement effect cannot be obtained in the above operation, while the content is 1%.
If it exceeds 0%, the toughness will decrease, so its content is determined to be 0.1 to 10%, preferably 0.3 to 3%.

(E) Mo The Mo component has a function of improving the strength by forming a solid solution in the base material and further improving the wear resistance by dispersing hard particles mainly composed of Mo alloyed with Fe or C. However, if the content is less than 0.1%, the desired strength improving effect cannot be obtained, while the content is 15%.
%, It is not preferable because toughness is reduced. Therefore, the content is 0.1 to 15%, preferably 0.1 to 15%.
5-10% was determined.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION The piston ring wear ring of the present invention will be specifically described with reference to examples. Example 1 As raw material powder, atomized Fe having an average particle size of 55 μm was used.
Powders, Cu—Ni alloy powders A to D having the average particle diameter and the component composition shown in Table 1, and graphite powder having an average particle diameter of 18 μm were prepared.

[0023]

[Table 1]

These raw material powders were blended in the composition shown in Table 2 and 0.7% of zinc stearate was added as a lubricant and mixed for 30 minutes in a V-type mixer.
It was pressed into a green compact under a pressure of m ^2, the green compact N ₂ -
By sintering in a 10% H ₂ atmosphere at a temperature of 1140 ° C. for 30 minutes, it has the component composition shown in Table 2, and has dimensions of outer diameter: 120 mm × inner diameter: 102 mm × thickness: 7 mm Of the present invention (hereinafter, referred to as the present invention). As shown in the sketch of the metal structure in FIG. 1, each of the above wear rings 1 to 10 of the present invention is composed of a Fe-based alloy phase 1 mainly composed of Fe and a Cu-based alloy phase 2 mainly composed of Cu. It had a bonded base, and fine precipitated free graphite 3 was dispersed in the base.

Further, the contents of the Fe-based alloy phase and the Cu-based alloy phase in the structures of the wear-resistant rings 1 to 10 of the present invention are expressed by E
As a result of measurement by PMA, the Fe-based alloy phase was Ni,
It contains Cu and C and contains Fe by 50% by weight or more, and the Cu-based alloy phase contains Ni, Fe and C and contains Cu by 50% by weight or more, and further contains Ni and Fe contained in the Fe-based alloy phase. It was found that the concentration of C was higher than the concentrations of Ni and C contained in the Cu-based alloy phase. Furthermore, for comparison purposes, in a normal high-frequency melting furnace,
Similarly, a melt of niresist cast iron having the component composition shown in Table 2 is prepared and cast into a shell mold to produce a conventional piston ring wear ring (hereinafter referred to as a conventional wear ring) having the same dimensions. did.

Next, the above-mentioned various wear rings are pretreated under ordinary conditions, ie, degreasing, drying, and temperature: 700 ° C.
After being pretreated for immersion for 5 minutes in an Al-Si alloy melt having the same composition as the cast Al-Si alloy melt described below, each was placed in a precision casting mold, and Al
-12.4% Si-1.12% Cu-0.96% Mg-
A piston body is formed by casting a molten Al-Si alloy having a composition of 1.06% Ni, and the various wear rings are cast-in. Then, grooves are formed by cutting along the outer peripheral surface of the wear rings. By forming a top ring groove having a dimension of depth: 7 mm x groove width: 3 mm, an Al-Si alloy piston having a wear-resistant ring having the top ring groove was manufactured.

Further, these pistons are provided with a displacement of 8
Installed in a 200cc direct-injection 6-cylinder direct-injection diesel engine, rotation speed: 3500 rpm, engine cooling temperature:
An accelerated operation test is performed under the conditions of 95 ° C., operation mode: 500 hours continuous operation, load: full output, and the maximum groove width increase of the outer peripheral surface in the top ring groove of the wear-resistant ring after the test (maximum groove width—by cutting) The high-temperature wear resistance was evaluated by measuring the formed groove width), and the piston ring (Fe-2.7% Si-3.
The aggressiveness of the partner was evaluated by measuring the maximum wear depth on the upper and lower surfaces of a spheroidal graphite cast iron having a composition of 5% C and plated with Cr. Table 2 shows the results of these measurements.

[0028]

[Table 2]

From the results shown in Table 2, it can be seen that the present wear ring 1
Nos. 10 to 10 show excellent high-temperature wear resistance because the maximum groove width increase is small, and have extremely low opponent aggression, whereas conventional wear-resistant rings made of niresist cast iron have sufficient high-temperature wear resistance. It is apparent that the maximum ring width increase amount of the top ring groove is unfavorable because of not having the above.

Example 2 Atomized Fe having an average particle size of 55 μm was used as a raw material powder.
Powder, a Cu—Ni alloy powder having an average particle diameter and a component composition shown in Table 1, a graphite powder having an average particle diameter of 18 μm were prepared, and further having an average particle diameter of 40 μm.
Contains a predetermined amount in the range of 20 to 80%, the balance being Fe-Cr alloy powder composed of Fe and unavoidable impurities, having an average particle size of 50 μm, and having a Mo of 0.5 shown in Table 3. A predetermined amount in the range of ~ 15%, and the balance: Fe
And an Fe-Mo alloy powder composed of unavoidable impurities.

These raw material powders were blended in the composition shown in Table 3, zinc stearate (0.7%) was added as a lubricant and mixed with a V-type mixer for 30 minutes.
It was pressed into a green compact under a pressure of m ^2, the green compact N ₂ -
By sintering in a 10% H ₂ atmosphere at a temperature of 1140 ° C. for 30 minutes, it has the component composition shown in Table 4, and has dimensions of outer diameter: 120 mm × inner diameter: 102 mm × thickness: 7 mm The present invention anti-friction rings 11 to 20 were produced respectively. As shown in the sketch of the metallographic structure in FIG. 1, each of the above wear-resistant rings 11 to 20 of the present invention has a base obtained by bonding Fe-based alloy phase 1 with Cu-based alloy phase 2,
Fine precipitated free graphite 3 was dispersed in the base material.

Further, the content of the Fe-based alloy phase and the Cu-based alloy phase constituting the base material of the piston ring made of free graphite-precipitated iron-based sintered gold alloy ring of the present invention was measured by EPMA. Are Ni, Cu and C
And further containing Cr and / or Mo, and Fe
And the Cu-based alloy phase is N
i, Fe and C and further Cr and / or Mo
, And at least 50% by weight of Cu, and furthermore, the concentrations of Ni and C contained in the Fe-based alloy phase and Cr
It has been found that the concentration of and / or Mo is higher than the concentration of Ni and C and the concentration of Cr and / or Mo contained in the Cu-based alloy phase.

Next, each of the above-mentioned various wear rings was placed in a precision casting mold in a state where it was subjected to a pretreatment of immersion in an Al-Si alloy melt for 5 minutes in the same manner as in Example 1.
Al-12.4% Si-1.12% Cu-0.9
A molten Al-Si alloy having a composition of 6% Mg-1.06% Ni is cast to form a piston body, the wear ring is cast in, and then cut along the outer peripheral surface of the wear ring. By forming a top ring groove having a groove depth of 7 mm × groove width: 3 mm, pistons made of Al—Si alloys were manufactured.

Further, these pistons were incorporated in an in-line 6-cylinder direct-injection diesel engine with a displacement of 8200 cc in the same manner as in Example 1, the number of revolutions was 3500 rpm, the cooling temperature of the engine was 95 ° C., and the operation mode was continuous for 500 hours. Operation and load: Perform an acceleration operation test under the condition of full output,
Maximum groove width increase on the outer peripheral surface of the top ring groove of the wear ring after the test (maximum groove width-groove width formed by cutting)
Is measured to evaluate the high-temperature wear resistance, and the piston ring (Fe-
(Materials made of spheroidal graphite cast iron having a composition of 2.7% Si-3.5% C and Cr-plated). Are shown in Table 4.

[0035]

[Table 3]

[0036]

[Table 4]

From the results shown in Table 4, it can be seen that the present wear ring 1
Nos. 1 to 20 all show excellent high-temperature wear resistance and have extremely low aggressiveness on the other side, whereas the conventional wear rings made of the niresist cast iron shown in Table 2 do not have sufficient high-temperature wear resistance. Therefore, it is clear that the progress of wear is remarkable.

Example 3 Instead of the Fe—Mo alloy powder in Example 2, the powder had an average particle size of 30 μm, and the Fe content exceeded 15 as shown in Table 5.
The same raw material powder as in Example 2 was prepared, except that a Fe-Mo alloy powder containing a predetermined amount within a range of 60% and the balance: Mo and unavoidable impurities was prepared.

These raw material powders were mixed in the composition shown in Table 5, and 0.7% of zinc stearate was added as a lubricant and mixed for 30 minutes with a V-type mixer.
It was pressed into a green compact under a pressure of m ^2, the green compact N ₂ -
By sintering in a 10% H ₂ atmosphere at a temperature of 1140 ° C. for 30 minutes, it has the component composition shown in Table 6, and has dimensions of outer diameter: 120 mm × inner diameter: 102 mm × thickness: 7 mm The present invention wear-resistant rings 21 to 30 having the following were produced. Each of the above-described wear rings 21 to 30 of the present invention has a base obtained by combining an Fe-based alloy phase with a Cu-based alloy phase, and fine precipitated free graphite is dispersed in the base. Hard particles (not shown) as components were also dispersed.

Further, as a result of measuring the composition of Fe-based alloy phase and Cu-based alloy phase by EPMA, it was found that the Fe-based alloy phase was Ni, 50% by weight containing Cu and C and further containing Cr and / or Mo and Fe
The Cu-based alloy phase contains Ni, Fe and C, further contains Cr and / or Mo, and contains Cu
, 50% by weight or more, and the concentrations of Ni and C contained in the Fe-based alloy phase and Cr and / or M
It was found that the concentration of o was higher than the concentrations of Ni and C and the concentrations of Cr and / or Mo contained in the Cu-based alloy phase.

Next, each of the above-mentioned various wear rings was placed in a precision casting mold in a state where it was pretreated by immersion for 5 minutes in an Al-Si alloy melt in the same manner as in Example 1.
Al-12.4% Si-1.12% Cu-0.9
A molten Al-Si alloy having a composition of 6% Mg-1.06% Ni is cast to form a piston body, the wear ring is cast in, and then cut along the outer peripheral surface of the wear ring. By forming a top ring groove having a groove depth of 7 mm × groove width: 3 mm, pistons made of Al—Si alloys were manufactured.

Further, these pistons were incorporated in an in-line 6-cylinder direct-injection diesel engine having a displacement of 8200 cc in the same manner as in Example 1, the number of revolutions was 3500 rpm, the cooling temperature of the engine was 95 ° C., and the operation mode was continuous for 500 hours. Operation and load: Perform an acceleration operation test under the condition of full output,
Maximum groove width increase on the outer peripheral surface of the top ring groove of the wear ring after the test (maximum groove width-groove width formed by cutting)
Is measured to evaluate the high-temperature wear resistance, and the piston ring (Fe-
(Materials made of spheroidal graphite cast iron having a composition of 2.7% Si-3.5% C and Cr-plated). Are shown in Table 6.

[0043]

[Table 5]

[0044]

[Table 6]

From the results shown in Table 6, it can be seen that the present wear ring 2
Nos. 1 to 30 all show excellent high-temperature wear resistance and have extremely low aggressiveness on the other side, whereas the conventional wear rings made of the niresist cast iron shown in Table 2 do not have sufficient high-temperature wear resistance. Therefore, it is clear that the progress of wear is remarkable.

[0046]

As described above, the piston ring anti-wear ring of the present invention exhibits excellent high-temperature abrasion resistance with low opponent aggressiveness even in a high-temperature atmosphere. It has sufficient industrial characteristics, such as being able to respond satisfactorily and contributing to an increase in the output and size of the engine.

[Brief description of the drawings]

FIG. 1 is a sketch of the structure of the piston ring wear ring of the present invention.

FIGS. 2A and 2B are a schematic longitudinal sectional view illustrating a piston of a diesel engine and a longitudinal sectional view of a main part of the same.

[Explanation of symbols]

 1 Fe-based alloy phase, 2 Cu-based alloy phase, 3 Free graphite phase

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F16J 9/00 F16J 9/00 A // C22C 33/02 103 C22C 33/02 103E F-term (Reference) 3J044 AA02 AA08 BA03 BA09 BA10 CA07 DA09 4K018 AA29 AB07 AC01 BA14 BA20 DA11 HA04 JA02 KA09

Claims (10)

[Claims] 1. The composition according to claim 1, wherein in weight% Cu: 11-40%, Ni:
0.5 to 10%, C: 0.8 to 3%, the balance being F
e and a composition composed of unavoidable impurities, and a structure in which precipitated free graphite is dispersed in a matrix formed by combining an Fe-based alloy phase mainly containing Fe with a Cu-based alloy phase mainly containing Cu. An iron-based sintered ring made of an iron-based sintered gold-free bonded graphite having excellent high-temperature wear resistance and heat conductivity, which is made of an iron-based sintered alloy. 2. The Fe-based alloy phase containing Fe as a main component,
F containing Ni, Cu and C and containing 50% or more of Fe
an e-based alloy phase, wherein the Cu-based alloy phase containing Cu as a main component is a Cu-based alloy phase containing Ni, Fe, and C and containing 50% or more of Cu; 2. The iron-based sintered gold alloy according to claim 1, wherein the concentration of C is higher than the concentrations of Ni and C contained in the Cu-based alloy phase. Piston ring wear ring. 3. In weight%, Cu: 11-40%, Ni:
0.5 to 10%, C: 0.8 to 3%, Cr: 0.1 to 1
0%, the balance being Fe and unavoidable impurities; and free graphite precipitated in a matrix formed by combining an Fe-based alloy phase mainly composed of Fe with a Cu-based alloy phase mainly composed of Cu. A piston ring wear ring made of iron-bonded iron-base sintered gold, which is excellent in high-temperature wear resistance and heat conductivity, and is made of an iron-based sintered alloy having a structure in which is dispersed. 4. The Fe-based alloy phase containing Fe as a main component,
A Fe-based alloy phase containing Ni, Cu, Cr and C and containing 50% or more of Fe, wherein the Cu-based alloy phase containing Cu as a main component is Ni, Fe,
It is a Cu-based alloy phase containing Cr and C and containing 50% or more of Cu, and the concentration of Ni, Cr and C contained in the Fe-based alloy phase is determined by the concentration of Ni, Cr and C contained in the Cu-based alloy phase. The piston ring wear ring made of a free graphite-precipitated iron-base sintered metal having excellent high-temperature abrasion resistance and heat conductivity according to claim 3, characterized in that the concentration is higher than the concentration. 5. The composition according to claim 1, wherein Cu: 11 to 40%, Ni:
0.5 to 10%, C: 0.8 to 3%, Mo: 0.1 to 1
5%, the balance being Fe and unavoidable impurities, and free graphite precipitated in a matrix formed by combining an Fe-based alloy phase mainly composed of Fe with a Cu-based alloy phase mainly composed of Cu. A piston ring wear ring made of iron-bonded iron-base sintered gold, which is excellent in high-temperature wear resistance and heat conductivity, and is made of an iron-based sintered alloy having a structure in which is dispersed. 6. In weight percent, Cu: 11-40%, Ni:
0.5 to 10%, C: 0.8 to 3%, Mo: 0.1 to 1
A composition containing 5%, with the balance being Fe and inevitable impurities, and free graphite precipitated in a matrix formed by combining an Fe-based alloy phase mainly composed of Fe with a Cu-based alloy phase mainly composed of Cu. Made of iron-based sintered gold, which is free graphite-precipitated, excellent in high-temperature wear resistance and thermal conductivity, characterized by comprising an iron-based sintered alloy having a structure in which hard particles containing Mo and Mo as a main component are dispersed. Piston ring wear ring. 7. The Fe-based alloy phase containing Fe as a main component,
An Fe-based alloy phase containing Ni, Cu, Mo and C and containing 50% or more of Fe, wherein the Cu-based alloy phase containing Cu as a main component is Ni, Fe,
It is a Cu-based alloy phase containing Mo and C and containing 50% or more of Cu, and the concentrations of Ni, Mo, and C contained in the Fe-based alloy phase are the same as those of Ni, Mo, and C contained in the Cu-based alloy phase. 7. A wear ring for a piston ring made of iron-base-sintered bonded gold having free graphite and excellent heat resistance and high heat resistance according to claim 5 or 6, which is higher than the concentration. 8. In weight%, Cu: 11 to 40%, Ni:
0.5 to 10%, C: 0.8 to 3%, Mo: 0.1 to 1
5%, Cr: 0.1 to 10%, the balance being Fe and unavoidable impurities, and Fe-based alloy phase mainly composed of Fe bonded by Cu-based alloy phase mainly composed of Cu Made of an iron-based sintered alloy having a structure in which precipitated free graphite is dispersed in a base material, the iron-based sintered alloy having excellent high-temperature wear resistance and heat conductivity, characterized by having an iron-based sintered alloy. Piston ring wear ring. 9. In% by weight, Cu: 11 to 40%, Ni:
0.5 to 10%, C: 0.8 to 3%, Mo: 0.1 to 1
5%, Cr: 0.1 to 10%, the balance being Fe and unavoidable impurities, and Fe-based alloy phase mainly composed of Fe bonded by Cu-based alloy phase mainly composed of Cu Excellent high-temperature wear resistance and thermal conductivity characterized by being composed of an iron-based sintered alloy having a structure in which hard particles mainly composed of precipitated free graphite and Mo are dispersed in a base material formed by Piston rings made of free graphite-precipitated iron-base bonded gold. 10. The Fe-based alloy phase containing Fe as a main component is an Fe-based alloy phase containing Ni, Cu, Mo, Cr, and C and containing 50% or more of Fe, and containing the Cu as a main component. The Cu-based alloy phase includes Ni, Fe,
C containing Mo, Cr and C and containing 50% or more of Cu
a Ni-based alloy phase, Ni, Mo, Cr and C contained in the Fe-based alloy phase
Is determined by the concentration of Ni, Mo, C contained in the Cu-based alloy phase.
10. The piston ring wear ring made of iron-based sintered bonded iron based on free graphite deposited with excellent high-temperature abrasion resistance and heat conductivity according to claim 8 or 9, wherein the concentration is higher than the concentrations of r and C.