JPH02118041A - High strength and high toughness cu-base sintered alloy having excellent wear resistance - Google Patents

Abstract

PURPOSE:To obtain the title sintered alloy by specifying the compsn. constituted of Zn, Al, Mn, Si, W, Mo, O and Cu and forming its structure into the one of which oxide and intermetallic compounds are uniformly dispersed into a matrix. CONSTITUTION:The high strength and high toughness Cu-base sintered alloy has the compsn. contg., by weight, 10 to 40% Zn, 0.3 to 6% Al, 0.1 to 5% Mn, 0.1 to 3% Si, 0.1 to 3% W and/or Mo and 0.03 to 1% O, furthermore contg., at need, 0.1 to 5% of one or more kinds among Fe, Ni and Co and one or both of 0.1 to 4% Sn and 0.1 to 3% Cr and the balance Cu with inevitable impurities and has the structure of which fine oxide and intermetallic compounds consisting essentially of Al2O3 are uniformly dispersed into a matrix. The alloy has excellent wear resistance and furthermore has excellent synchronizing characteristics for the mating members evaluated by friction coefficient. Thus, the alloy is preferably suitable as the structural member of various apparatus in which miniaturizing, lightening and high outputting are required.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention has excellent wear resistance, high strength and toughness, and also has excellent synchronization characteristics with respect to a mating member, which is evaluated by the coefficient of friction. Therefore, the present invention relates to a Cu-based sintered alloy suitable for use in synchronizer rings for transmissions, valve guides for engines, bearings for turbochargers, etc., which require these characteristics.

[Conventional technology]

Conventionally, Cu-2g96 Zn-6 was used in the production of the various members mentioned above in weight% (hereinafter % indicates weight 96).
It has been proposed to use a Cu-based sintered alloy having a typical composition of %Ag.

[Problem to be solved by the invention]

However, since the above-mentioned conventional Cu-based sintered alloy is a sintered body, although it has excellent synchronization characteristics with respect to a mating member, it does not have sufficient wear resistance, strength, and toughness. Therefore, the development of Cu-based sintered alloys that have even better wear resistance, high strength, and high toughness is strongly desired, as it is not possible to keep up with the recent trends in miniaturization, weight reduction, and high output of various types of equipment. It is rare.

[Means to solve the problem]

Therefore, the inventors of the present invention have taken the above-mentioned view into consideration.
Focusing on the conventional Cu-based sintered alloy described above, we conducted research to develop a Cu-based sintered alloy with significantly superior wear resistance, strength, and toughness, and found that Zn: 10-40%,
AR: 0.3 to 6%, Mn: O, 1 to 5
%, Si: 0.1-3%, one or two of W and Mo: 0.1-3%, oxygen: 0.03-1%, and further as necessary , (il) One or more of Fe, Ni, and Co: 0.1 to 5%, (b) 5 units 20, 1 to 4%, (c) Cr: 0.1 to 3 %, a composition containing any one or two or more of the above (a) to (C), with the remainder consisting of Cu and inevitable impurities,
In addition, the Cu-based sintered alloy, which has a single weave in which fine oxides and intermetallic compounds mainly composed of aluminum oxide (Ag2O3) are uniformly dispersed, has excellent wear resistance, high strength and Since it has electric properties, it has been found that it can be applied to the production of structural members that can sufficiently respond to the miniaturization and weight reduction of various devices and the increase in output.

This invention was made based on the above findings, and the Cu-based sintered alloy of this invention has the above composition:
A (
A structure in which oxides mainly composed of 120a are uniformly dispersed at an area ratio of 0.5 to 1596, and intermetallic compounds also distributed within the particle size range of 1 to 25 μs are uniformly dispersed at an area ratio of 1 to 10%. These oxides and intermetallic compounds significantly improve wear resistance, and in particular, uniform dispersion of oxides improves seizure resistance and improves the heat resistance of friction surfaces. In addition to this, it also shows excellent wear resistance even under high load conditions.

Next, the reason for limiting the component composition as described above in the Cu-based sintered alloy of the present invention will be explained.

(a) Two Zn components include Cu and AJl! If the content is less than 10%, the desired effect cannot be obtained; on the other hand, if the content exceeds 40%, the Since deterioration phenomenon appears in the action, its content is set at 10 to 40%.

(b) AN Ap component not only forms a matrix with Cu and Zn that has high strength and high toughness as described above, but also combines with oxygen to form an oxide, so it is resistant not only to room temperature but also to high temperature conditions. If the content is less than 0.3%, the desired effect cannot be obtained, while if the content exceeds 6%, the toughness of the substrate decreases. Therefore, its content was determined to be 0.3 to 6%.

(c) Mn The Mn component combines with Sl to form an intermetallic compound that is finely dispersed in the base material to improve wear resistance, and a part of it is dissolved in the base material to improve strength. However, if the content is less than 0.1%, the desired effect will not be obtained, while if the content exceeds 5%, the toughness will decrease. from 0.1
It was set at 5%.

(d) The 5I Sl component combines with Mn, W, Mo, and Cr contained as necessary to form a hard and fine intermetallic compound, and also combines with oxygen to form complexes with 8Ω, etc. Forms oxides to improve wear resistance, and in particular, the presence of the above-mentioned double oxides improves seizure resistance and heat resistance of friction surfaces as described above, so it is excellent even under high load conditions. However, if the content is less than 0.1%, the desired wear resistance cannot be achieved, while if the content exceeds 3%, the toughness decreases. Therefore, the inclusion amount was set at 0.1 to 3%.

(c) W and M.

In addition to improving strength, these components combine with Fe, Nl, and CO contained as necessary to form fine intermetallic compounds, and also combine with oxygen to form fine oxides. However, it has the effect of improving wear resistance.
If the content is less than 0.1%, the desired strength and wear resistance cannot be secured, while if the content exceeds 3%, the toughness decreases, so the content is reduced to 0.1%.
It was set at ~3%.

(f') Oxygen As mentioned above, oxygen includes Ag, St, W, and Mo.
, further combines with Cr contained as necessary to form oxides that are finely and uniformly dispersed in the base material, thereby improving wear resistance, and in particular, improving seizure resistance and heat resistance. It has the effect of improving wear resistance under load conditions, but if its content is less than 0.03%, the formation of oxides is too small to ensure the desired wear resistance; If the amount exceeds 1%, the oxide particle size will decrease to 40mm.
Not only will the alloy become coarser, but the area ratio will exceed 15%, which will reduce the strength and toughness of the alloy, as well as increase its aggressiveness.
Its content was determined to be 0.03 to 1%.

(g) Fe, Ni, and CO These components are dispersed in the matrix to improve the strength and toughness of the alloy, and include Cu and Ag1, as well as W,
It combines with Mo and Cr to form fine intermetallic compounds that are dispersed in the base material and has the effect of improving wear resistance, so it is included as necessary, but its content is 0.1%.
If the content is less than 5%, the desired effect cannot be obtained, while if the content exceeds 5%, the toughness will decrease, so the content was set at 0.1 to 5%.

(h) The 5n Sn component includes solid solution in the base material to strengthen it.
Since it has the effect of improving seizure resistance under high load conditions and thereby contributing to improvement of wear resistance, H is added as necessary, but if the content is less than 0.1%, On the other hand, if the content exceeds 4%, not only will the toughness decrease, but also the heat resistance of the friction surface will decrease, and the wear resistance will be impaired. Therefore, its content was determined to be 0.1 to 4%.

(i) The CrC component, like W and Mo, forms intermetallic compounds with iron group metals contained as necessary, and also forms oxides, which have the effect of further improving wear resistance. Therefore, H content is added as needed, but the amount of 0.1%
If the content is less than 3%, the desired effect of improving wear resistance cannot be obtained, while if the content exceeds 3%, the toughness will decrease. Ta.

The CuJJ sintered alloy of the present invention may contain P, Mg, and Pb as unavoidable impurities, but if the total content is 1.5% or less, the alloy properties will not be impaired in any way. Therefore, its inclusion is permissible.

〔Example〕

Next, the Cu-based sintered alloy of the present invention will be specifically explained with reference to Examples.

As raw material powders, each has a particle size of 200mcsh or less, and by adjusting the layer thickness of the surface oxidation layer, the 0□ content is set to 4% and 2%, respectively!2fl! If Cu
-Ap gold alloy (Ail: 50% content) powder, Cu powder, Z
n powder, Ag powder, Mn powder, S1 powder, W powder, Mo
Powder, Fe powder, Ni powder, Co powder, Sn powder, and C powder were prepared, and these raw material powders were each blended into the composition shown in Table 1, pulverized and mixed in a ball mill for 72 hours, and dried. After that, it was press-molded into a compact at a predetermined pressure within the range of 4 to 6 ton/cd, and then heated at 800 to 90 ton/cd in an H2 gas atmosphere with a dew point of 20 to -30 °C.
By sintering under the conditions of holding at a predetermined temperature within the range of 0℃ for 1 hour, it has dimensions of outer diameter near 0 x inner diameter: 02 mm x thickness: 8 cm as a crushing load M1, and is also suitable for wear testing. The dimensions are width: 10 mm x thickness: 10 mm x length: 40 mm, and the outer diameter is 1 as defined by the friction coefficient A-j.
Each has dimensions of 0 favorite x height: 20Il111,
Cu-based sintered alloys 1 to 30 of the present invention, comparative CuJJi sintered alloys 1 to 7, and conventional Cu-based sintered alloys, all of which had substantially the same composition as the compounded composition, were manufactured.

The Cu-based sintered alloys 1 to 30 of the present invention all had a structure in which fine oxides and intermetallic compounds were uniformly dispersed in the base material.

In addition, all of Comparative Cu-based sintered alloys 1 to 7 have a component a content (marked in brown in Table 1) of one of the constituent components outside the scope of the present invention. .

Next, the strength and toughness of the various Cu-based sintered alloys obtained as a result were evaluated.
For the purpose of determining ll+ and further evaluating wear resistance, specimen shape: 8 mm x 8 m + s x 30 mm, mating material:
The material is 5UH3 (i, outer diameter: 30 + am x width: 5
1 ring, oil, 5W engine oil, oil temperature: 80℃, friction speed: 8m/sec, final load: 5kg.

A block-on-ring wear test was conducted under the conditions of sliding distance: 1.5 kffi, to determine the specific wear amount at 4 pj, and to further evaluate the synchronization characteristics with respect to the mating member.Trial shape: a bottle with a diameter of 2++ m, Mating material: 5U
H3B disc, Oil: 5W engine oil, Ura temperature: 80℃, Friction speed: 8m/see, Pressure Crab 2kgTh Sliding distance *: +. A bottle friction ttX test was conducted under the condition of 5 km, and the 4 friction coefficient was calculated from a torque meter. These results are shown in Table 1.

〔Effect of the invention〕

From the results shown in Table 1, Cu-based sintered alloys 1 to 1 of the present invention
No. 30 has a coefficient of friction H equivalent to that of conventional Cu-based sintered alloys, which indicates that they have excellent synchronization characteristics with respect to the mating member, and also have superior durability compared to conventional Cu-based sintered alloys. However, as seen in Comparative CuM sintered alloys 1 to 7, if the content of any of the constituent components falls outside the scope of the present invention, the wear resistance is poor. It is clear that at least one of the properties of toughness, strength, and toughness becomes inferior.

As mentioned above, the Cu-based sintered alloy of the present invention has excellent wear resistance, high strength and toughness, and also has excellent synchronization characteristics with respect to the mating member, so it can be miniaturized and It can be used as a structural member for various types of equipment that require light weight and high output, and when put into practical use, it shows excellent performance over a long period of time. It has extremely useful properties.

Claims (8)

[Claims] (1) Zn: 10-40%, Al: 0.3-6%, Mn
: 0.1-5%, Si: 0.1-3%, one or two of W and Mo: 0.1-3%, oxygen: 0.03-1%, and the rest Excellent wear resistance, characterized by a composition consisting of Cu and unavoidable impurities (wt%), and a structure in which fine oxides mainly consisting of aluminum oxide and intermetallic compounds are uniformly dispersed in the matrix. A high-strength, high-toughness Cu-based sintered alloy. (2) Zn: 10-40%, Al: 0.3-6%, Mn
: 0.1 to 5%, Si: 0.1 to 3%, one or two of W and Mo: 0.1 to 3%, oxygen: 0.03 to 1%, and further contains , one or more of Fe, Ni, and Co:
0.1 to 5%, with the remainder consisting of Cu and unavoidable impurities (weight%), and a structure in which fine oxides and intermetallic compounds mainly composed of aluminum oxide are uniformly dispersed in the matrix. A high-strength, high-toughness Cu-based sintered alloy with excellent wear resistance. (3) Zn: 10-40%, Al: 0.3-6%, Mn
: 0.1 to 5%, Si: 0.1 to 3%, one or two of W and Mo: 0.1 to 3%, oxygen: 0.03 to 1%, and further contains , Sn: 0.1 to 4%, and the remainder is Cu and unavoidable impurities (weight%), and fine oxides and intermetallic compounds mainly composed of aluminum oxide are uniformly contained in the matrix. A high-strength, high-toughness Cu-based sintered alloy with excellent wear resistance characterized by having a dispersed structure. (4) Zn: 10-40%, Al: 0.3-6%, Mn
: 0.1 to 5%, Si: 0.1 to 3%, one or two of W and Mo: 0.1 to 3%, oxygen: 0.03 to 1%, and further contains , Cr: 0.1 to 3%, with the remainder consisting of Cu and unavoidable impurities (wt%), and fine oxides and intermetallic compounds mainly composed of aluminum oxide are uniformly contained in the matrix. A high-strength, high-toughness Cu-based sintered alloy with excellent wear resistance characterized by having a dispersed structure. (5) Zn: 10-40%, Al: 0.3-6%, Mn
: 0.1 to 5%, Si: 0.1 to 3%, one or two of W and Mo: 0.1 to 3%, oxygen: 0.03 to 1%, and further contains , one or more of Fe, Ni, and Co:
0.1 to 5%, Sn: 0.1 to 4%, and the remainder is Cu and unavoidable impurities (weight %), and a fine oxide mainly consisting of aluminum oxide in the base material. and a high-strength, high-toughness Cu-based sintered alloy with excellent wear resistance, characterized by having a structure in which intermetallic compounds are uniformly dispersed. (6) Zn: 10-40%, Al: 0.3-6%, Mn
: 0.1 to 5%, Si: 0.1 to 3%, one or two of W and Mo: 0.1 to 3%, oxygen: 0.03 to 1%, and further contains , one or more of Fe, Ni, and Co:
Cr: 0.1 to 5%, Cr: 0.1 to 3%, and the remainder is Cu and unavoidable impurities (wt%), and a fine oxide mainly consisting of aluminum oxide in the base material. and a high-strength, high-toughness Cu-based sintered alloy with excellent wear resistance, characterized by having a structure in which intermetallic compounds are uniformly dispersed. (7) Zn: 10-40%, Al: 0.3-6%, Mn
: 0.1 to 5%, Si: 0.1 to 3%, one or two of W and Mo: 0.1 to 3%, oxygen: 0.03 to 1%, and further contains , contains Sn: 0.1 to 4%, Cr: 0.1 to 3%,
Composition with the remainder consisting of Cu and unavoidable impurities (more than % by weight)
, and a high-strength, high-toughness C with excellent wear resistance, characterized by having a structure in which fine oxides mainly composed of aluminum oxide and intermetallic compounds are uniformly dispersed in the base material.
U-based sintered alloy. (8) Zn: 10-40%, Al: 0.3-6%, Mn
: 0.1 to 5%, Si: 0.1 to 3%, one or two of W and Mo: 0.1 to 3%, oxygen: 0.03 to 1%, and further contains , one or more of Fe, Ni, and Co:
0.1 to 5%, Sn: 0.1 to 4%, and Cr: 0.1 to 3%, with the remainder consisting of Cu and unavoidable impurities (wt%), and oxidation in the base material. A high-strength, high-toughness Cu-based sintered alloy with excellent wear resistance, characterized by having a structure in which fine oxides and intermetallic compounds mainly composed of aluminum are uniformly dispersed.