JPS5950223A - Sliding member - Google Patents

Abstract

PURPOSE:To greatly reduce the wear and improve the seizure resistance with respect to a cylinder liner by using silicon nitride for one member of the sliding members and using a material sprayed with a chromium oxide for the sliding surface material of the partner member. CONSTITUTION:One member of a pair of slidable members is made of silicon nitride and the sliding part of other member is made of the sprayed layer of chromium oxide. The member having the sliding part made up of silicon nitride may be a member made up independently of silicon nitride ceramics of a member formed by subjecting the silicon nitride ceramics to lining on a metal mother material. As silicon nitride ceramics a sintered body sintered by an ordinary method can be employed. Joining of the silicon nitride sintered body with the metal is made by a thermal inserting method. In order to form a film of a chromium oxide powder sprayed layer, plasma spraying is particularly preferable.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sliding member that can be used in various situations, such as piston rings for piston rings and cylinder liners.

In recent years, fuel gf' has been developed for the purpose of improving fuel efficiency in internal combustion engines.
Research and development is underway to make the combustion chamber more heated, but due to the insulation of the combustion chamber, the sliding surface between the piston ring and cylinder liner does not reach high temperatures, making oil exchange breakage more likely. As a result, seizure and excessive wear between the piston ring and cylinder liner are likely to occur.

Conventionally, as one of the countermeasures against such problems, the sliding part of the outer circumferential surface of iron-based piston rings is not coated with chrome plating, molybdenum thermal spraying, or iron chrome base metal thermal spraying, thereby reducing the wear resistance coating layer by 1φ. It is well known that it can be formed, and its applications are wide. However, if all silicon nitride is added to the cylinder liner in order to achieve rapid heating, seizures and excessive machining are likely to occur.

The present invention has been made to solve the problems of the above-mentioned prior art.
The newly released JIA stand has a piston ring sliding part that has better seizure resistance and +Art K resistance than the conventional Yoho mater surface that has been sprayed with molybdenum or iron chrome. The purpose is to provide money.

A piston ring having a spray resistance of extracted chromium (Cr203) formed by plasma spraying acid chromium powder on a slide 1IIj, which was researched for the purpose of the present inventors. The piston link itself does not wear out when moving, and the mating member is made of silicon nitride (n).
The present invention was completed by discovering C and T that do not attack and wear out all the opposing parts.

That is, in the sliding part of the present invention, one member of a pair of slidable members is made of arsenic silicon, and the sliding part of the other member is made of a reflective layer of chromium oxide. It is characterized by consisting of.

The member having a silicon nitride sliding part, which is a part of the present invention, may be a member made of silicon nitride ceramic alone, or may be a member made of a silicon nitride ceramic base material in which a silicon nitride ceramic is inked with gold. ``Nitrogen 11S silicon ceramics'' is a sintered body sintered by a standard method, and its shape can be used for the purposes mentioned above, such as the piston ring itself, its lining material, or the shape of other parts. It can be changed freely and is not limited.

The temperature between the sintered silicon rod and the sound electric device in chamber 1 is 300 to 500°C.
The entire metal body is placed in a furnace maintained at a temperature of 1.
Is there a shrink fit method in which a sintered body of cypress is inserted, slowly cooled to room temperature, and then fixed by the contraction of the main bridge? left is used. Alternatively, a silicon nitride coating is formed on the metal surface by sputtering gold-14 silicon thread on the surface of the base metal in a nitrogen atmosphere, and this is used as the sliding part side. You can also do that.

If the mating part is a piston ring, the mating part that slides on the above part side is made of cast iron. The provided material explodes when used.To form the entire film, arc bath irradiation,
Although there are methods such as dregs spraying or bladder 1fd spraying, plasma spraying is particularly preferable from the viewpoint of complications with the base material. Note that acid-ratio chromium (Crz03) powder sound is used for plasma spraying. It is desirable that the powder particle size be finer than 280 mesh (56μ); if the particle size is less than 88μ, the resulting sprayed layer will have many pores, resulting in poor +Ia+t rf tag properties and seizure resistance. The thickness of the sprayed layer is 0.1 to 0.
．． 25 screams are 54 beautiful. If it is thinner than 0.05 mm, the sprayed layer will not have a uniform thickness on six sides (Q), and if it is thicker than 0.3 mm, the sprayed layer will easily peel off.

A sprayed layer of 1-hydrochloric acid and 8 base metals on gold? J! ! In order to make the metal adherent, the I group base material is subjected to a pretreatment of blasting. The elbow of this shotblast [metal by surface 1υ, the surface of the material 411 heat is 20~4
0 μl 72 is preferred.

Furthermore, in order to improve the elasticity, N1-At 8 which has excellent layer properties with the metal base material is applied on the roughened metal matrix.
Powder (Meteco 450 manufactured by Metco), N j −Cr −
At (Meteco 443 manufactured by Metco) Is it a base with powder etc.? ? The effect is great when irradiation (direct irradiation #20 to 80μ) is applied.

Hereinafter, the entire assembly and implementation of the sliding member according to the present invention will be explained in detail, and it will be compared with the conventional one. l
In the examples, "%" represents 1 - production amount.

Example of piston ring made of spherical graphite @ iron outer diameter 35
．． 0 gates, inner diameter 61, 0 cm, floating type (11'l) 8.75
Using the same rotary test piece, a coating layer with a thickness of 0, i, 2 to 0.2 mm was completely formed on the outer circumferential surface of the roller by different treatment methods to obtain the following prints.

Chromium plated side (13) Fe-Cr alloy (composition: li'e-65
%Cr-8-, 2%C-1, 5%Si1 powdered rice grain size 10~
A member (Q Ni-AL powder (manufactured by Metco Co., Ltd., Metco 45
0) is formed by plasma spraying acid ratio chromium powder (manufactured by Metco, p106. Thermal spraying surface was treated with f'ilJ processing.

Each rotating test piece was treated as described above.The total length of each rotating test piece was 15.75 mm, which was a 4t J hand member (cylinder liner material).

Medium 6.35 pieces, height 10.2 mm ~ (D) Tsukujaku nishiki iron hammering Self-strike so that it is in contact with each end face (15,75 scale x 6.35 mm) of a hot-pressed Yahide silicon block test piece. Obstacles, on the side of insects? Supply 10W-30 pieces of motor oil as beak oil for one cycle, use a hair tester, and rotate e.
16 Orpm % MA'L for 1 hour with a load of 1180Kg
I carried out trial 1.

One round p class 19 plate cylinder liner Piston ring D A Comparative example D
43 D C 1zu A E B E C Example The test using the above combination is shown in the figure. In 1, the vertical axis above the horizontal axis is the wear amount (μ) of the block test piece? The vertical axis below the horizontal axis is the wear amount (
However, the codes in (4) to (g) are made to match the above-mentioned codes, and the following is clarified from the graph in the figure.

Comparing ■) and ■) as materials for cylinder liners, we found that conventional materials used for piston rings (D-A
, D-B, J-A, E-B), wear of ■ is (2)
Is* of the opponent member and (B) decreases more than .
ve m increases significantly. On the other hand, the piston ring according to the present invention (C)'! ! l-When used in stool, (C
) own wear amount is much lower than (A) and (B), but if the cylinder liner is made of (IJ) cast iron, the horse of (1)) will have a long wear (N (13) k It actually increases compared to when I got the 4J.

On the other hand, when the cylinder liner is made of silicon nitride from Co., Ltd., the tendency is completely opposite, and the 1ψ wear circle of the cylinder is the minimum (when compared to 0). The amount of wear (
5), which is much lower than (B).

Summarizing the above, r of fc) which is a component of the present invention
It can be said that the combination with the layer ratio (8) of silicon, which has the initial ROM sprayed layer, is most effective.

Example 2 Histonoring group made of spheroidal graphite iron as in Example ψ01,
The sliding surface of the IA was injected with machined chromium powder K4 onto the Ni-At base metal layer, and the piston ring for the actual 1-geometry test (the surface of the sliding surface) was 20, 5-2.0μRz)'i was manufactured by Kumaba 20.

Also, jJi chrome plating as a specific expropriation! We manufactured a piston/ring that was coated with iron-chromium and J-gold powder.

Each of the three types of pistons/rings mentioned above was installed in a diesel engine and a durability test was conducted using an actual machine. However, the diesel engine used is exhaust! :2188. . , cylinder hole'& 90 gates, stroke 86 +nm,
It was a 4 cycle, 4 cylinder type, and the cylinder liner was made of silicon nitride manufactured by the Honto press method. The test conditions were an engine rotation speed of 520 rpm, full load, and a continuous test of 500 hours using eaves oil as fuel.

As a result, the average wear amount in the thickness direction of the piston ring was 83μ for the chromium-plated ring and 55μ for the iron-chromium alloy sprayed piston ring, but only 8μ for the chromium oxide sprayed piston ring. It was extremely excellent and rare. In addition, while the former two have visible vertical scratches due to the sliding force and are showing signs of seizure, the chromium oxide sprayed version does not show any signs of seizure, and has excellent seizure resistance. was confirmed. In addition, the wear of the cylinder liner of the mating member t
It was confirmed that there were only minor problems and no problems except when combined with chrome-plated piston rings. Also 5
During the 00-hour test, the oil consumption and gas flow rate were better when all chromium oxide sprayed piston rings were used than in the other cases. This seems to be related to the difference in the amount of wear of the piston ring material.

The sliding member of the present invention has the above-described configuration, and the sliding surface S of one of the sliding members is made of silicon nitride, and the sliding surface of the mating member is made of a material sprayed with a chromium oxide alloy. By using the piston ring, the wear on the piston ring itself is reduced by a large amount rlJ compared to conventional piston ring materials.

- Wear of the cylinder 2 inner (silicon nitride) can be kept lower than that of conventional products or conventional M1 combinations.

■ The seizure resistance with the cylinder liner is the same as above.

■ Silicon nitride cylinder liners can be used without any problems, resulting in improved fuel efficiency.

In addition, secondary chromium oxide thermal spraying has the effect of reducing oil consumption and blow-by-case smoke (if).

[Brief explanation of the drawing]

The figure represents a graph showing the wear resistance of each sliding member combination of Example 1 of the present invention. (ha7〕)1 person)

Claims (1)

[Claims] Sliding port 1 i[: Among the pair of members, one member has a sliding portion made of silicon, and the sliding portion of the other member is made of a radiation layer of chromium. Characteristic sliding members.