WO2002053899A1

WO2002053899A1 - Internal combustion engine

Info

Publication number: WO2002053899A1
Application number: PCT/JP2001/010709
Authority: WO
Inventors: Syuhei Adachi; Masahiro Mihashi; Kenji Araki; Daisuke Nakao
Original assignee: Yamaha Motor Co., Ltd.
Priority date: 2000-12-07
Filing date: 2001-12-06
Publication date: 2002-07-11
Also published as: JPWO2002053899A1

Abstract

An internal combustion engine, comprising a cylinder block formed of an aluminum alloy sleeve cast in an aluminum alloy cast cylinder body, wherein the coefficient of linear expansion of the sleeve is smaller than that of the cylinder body; an internal combustion engine, comprising a cylinder block formed of an aluminum alloy sleeve disposed in an aluminum alloy cast cylinder body, wherein a piston is reciprocatingly stored in the cylinder of the cylinder block, and the coefficients of linear expansion of the sleeve, piston, and cylinder body are larger in that order as sleeve < piston < cylinder body.

Description

Description Internal Combustion Engine '' Technical Field

The present invention relates to an internal combustion engine provided with a cylinder port having a sleeve arranged in a cylinder body. Background art

For an internal combustion engine, a cylinder for an internal combustion engine is manufactured by wrapping a sleeve made of an aluminum alloy in a cylinder body made of an aluminum alloy, press-fitting or shrink-fitting the inner surface of the sleeve to apply a predetermined plating. There is a cylinder block provided with a piston, and a piston is reciprocally housed in the cylinder of the cylinder block. A cylinder block for an internal combustion engine is an important factor in achieving a high-performance engine with light weight and good thermal conductivity.

The aluminum alloy sleeve that is wrapped, press-fitted, or shrink-fitted into this cylinder hook for internal combustion engines has been manufactured by, for example, subjecting a forged pipe to a continuous, extruded pipe material to a predetermined process. . Conventionally, materials such as 12Si-13Cu-aluminum have been used for the sleeve material. The cylinder body was made of a highly moldable material such as JISAC2B in the case of a mold structure with good moldability, and the die body was made of a material with good moldability such as JISADC12 material.

By the way, when wrapping an aluminum alloy sleeve in an aluminum alloy cylinder body, the cylinder body is placed around the sleeve. While the molten metal on the side surrounds and the sleeve is heated and thermally expanded, as the cylinder body is gradually cooled after filling, the sleeve is also cooled and thermally contracted. The molten metal on the cylinder body shrinks when solidified by cooling, and further shrinks as the temperature decreases. If the linear expansion coefficient of the sleeve is high, the tightening force of the sleeve due to solidification shrinkage on the cylinder body side and heat shrinkage after solidification is reduced.

Also, in the operating state of the internal combustion engine, the temperature of the sleeve becomes lower than the temperature at the time of wrapping (a value close to the melting temperature of the aluminum alloy). About 0 ° C). In the internal combustion engine, if the coefficient of linear expansion of the sleeve is high, the tightening force of the sleeve remains relaxed, and a gap may be generated between the sleeve and the cylinder body. The gap between the cylinder body and the sleeve blocks heat transfer from the sleeve to the cylinder body side, causing hot spots and seizure with the piston.

Also, after completing the fabrication (normal temperature condition), the cylinder block and the piston are still attached to the cylinder block even if the specified finish is applied and the horn is finished to increase the cylindricity and roundness of the inner circumference of the sleeve. When the internal combustion engine is operated after the cylinder head has been assembled and the cylinder head has been bolted to complete the assembly of the internal combustion engine, the sleeve expands thermally. At this time, the rigidity increases around the plurality of bolt holes in the cylinder body around the sleeve where the cylinder head is bolted, and it resists thermal expansion, while it is the middle part of the bonnet hole around the sleeve Since the cylinder body has low resistance to thermal expansion, if the sleeve has a high linear expansion coefficient, the cylindricality and roundness of the inner circumference of the sleeve will not be maintained, and the combustion chamber and crank due to piston ring will not be maintained. Isolation from the chamber is reduced, oil consumption increases, and combustion gas blow-through The fuel consumption deteriorates and the oil deteriorates.

In addition, the sleeve material supporting the plating layer yielded and deteriorated due to the combustion pressure applied through the plating layer, the tension of the piston ring, and the like, and the plating layer could peel off from the sleeve material.

In addition, there is a rigidity gap by tightening the cylinder head, and the thermal expansion during operation is not uniform in each part of the sleeve in the circumferential direction. In particular, when the hardness is insufficient, the rigidity is low, and there are problems such as a large deformation due to thermal expansion in an intermediate portion of the cylinder head fastening port hole.

In addition, aluminum alloy sleeves are wrapped in a cylinder body made of aluminum alloy, and press-fitted or shrink-fitted, which is important for achieving a high-performance engine with light weight and good thermal conductivity. Element. In some cases, for example, a melt extruded material is used as the sleeve base material. In this case, the melt extruded material has a relatively low silicon (Si) content, and the coefficient of linear expansion is the same as that of the surrounding cylinder. It is equal to or less than aluminum material such as main body.

When the cylinder block of this combination is manufactured, for example, when the sleeve base material is wrapped by the aluminum die cast material, the sleeve base material and the aluminum alloy are solidified in the process of solidifying the aluminum die cast material. A gap may be formed between the objects, which may deteriorate the accuracy of the inner diameter grinding process in a subsequent process.

In addition, the presence of the gap causes the thermal conductivity to partially deteriorate, resulting in deterioration of the sleeve's cylindricity, roundness, and other shapes, leading to increased oil consumption and performance degradation.

The present invention has been made in view of such circumstances, and has an object to prevent seizure with a piston and to prevent deterioration of fuel efficiency and oil. The subject is.

Another object of the present invention is to prevent yield deterioration of the sleeve material, improve rigidity and reduce deformation due to thermal expansion, and reduce oil consumption while maintaining output performance. The goal is to make it possible. Disclosure of the invention

The present invention includes a cylinder block in which a sleeve made of an aluminum alloy is wrapped in a cylinder body made of aluminum alloy, and a coefficient of linear expansion of the sleeve is determined by a coefficient of linear expansion of the cylinder body. An internal combustion engine characterized by being smaller. Since the linear expansion coefficient of the sleeve is smaller than the linear expansion coefficient of the cylinder body, the sleeve tightening force due to solidification shrinkage on the cylinder body side and heat shrinkage after solidification does not decrease. There is no gap between them, and heat transfer from the sleeve to the cylinder body is good, making it a hot spot and preventing seizure with the piston.

Preferably, the coefficient of linear expansion of the sleeve is at least 10% smaller than the coefficient of linear expansion of the cylinder body, and the sleeve is caused by solidification shrinkage on the cylinder body side and heat shrinkage after solidification. The tightening force does not decrease further, and there is no gap between the sleeve and the cylinder body.

The aluminum alloy forming the sleeve preferably contains silicon (S i) in an amount of 15 to 38% by weight, and the silicon (S i) has an average particle diameter of 2 to 10%. / zm of primary crystal silicon (S i), and the sleeve has an average particle diameter of 20 to 100 m. It is preferable that the aluminum-containing powder is formed by coagulation and solidification, so that the coefficient of linear expansion of the sleeve can be made smaller, and the thermal conductivity, workability and plating properties are not impaired.

Further, the present invention includes a cylinder block having an aluminum alloy sleeve disposed in a cylinder body made of aluminum alloy, and a biston in the cylinder of the cylinder block. Is an internal combustion engine that reciprocates

The linear expansion coefficient of the piston, the sleeve, and the cylinder main body is characterized by that the cylinder main body has a sleeve <piston. By setting the linear expansion coefficient of the piston, sleeve, and cylinder body to that of the sleeve, the piston, and the cylinder, when the internal combustion engine is operated, the piston clearance due to the thermal expansion of the piston This makes it possible to keep the change in the oil in an ideal state, thereby making it possible to reduce loss and noise, and to reduce oil consumption while maintaining output performance.

Further, the aluminum alloy constituting the sleeve contains 1.8% by weight or less of magnesium (Mg), and the sleeve has a rock-well hardness (HRB) of 40 to 70. Preferably, at least one or more of copper (Cu), manganese (Mn), and zinc (Zn) are added to the aluminum alloy forming the sleeve in a total of 1.

It is preferable that the content be 7 to 8.3% by weight, so that the yield deterioration of the sleeve can be prevented, the rigidity can be improved, and deformation due to thermal expansion can be reduced.

In addition, it is preferable that the inner peripheral surface of the sleeve is subjected to a force re-etching process and then subjected to plating, and the outer surface of the sleeve is provided with a height of 0.1 to 2 mm in a length direction. When forming parallel continuous projections In both cases, it is preferable to uniformly distribute microcracks on the surface with a depth of 10 nm to a maximum of 20% of the sleeve base material thickness. BRIEF DESCRIPTION OF THE FIGURES

Figure 1 is a cross-sectional view of a water-cooled 4-cycle internal combustion engine with a dry-type sleeve.

FIG. 2 is a cross-sectional view taken along the line II-II of FIG.

Figure 3 is a cross-sectional view of a water-cooled four-stroke internal combustion engine with a wet sleeve.

FIG. 4 is a diagram showing a manufacturing process of a cylinder hook for an internal combustion engine. FIG. 5 is a view showing the state of the outer surface of the sleeve base material.

FIG. 6 is a diagram showing the relationship between the surface depth of the sleeve, the sleeve strength, and the interface gap.

Fig. 7 is a diagram showing Ni-P-SiC dispersed composite plating. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment of an internal combustion engine of the present invention will be described with reference to the drawings.

INDUSTRIAL APPLICABILITY The present invention is applied to a water-cooled or air-cooled four-stroke internal combustion engine and a two-stroke internal combustion engine having a cylinder opening for an internal combustion engine, and the sleeve is applied to a wet structure or a dry structure.

As an example of this internal combustion engine, FIGS. 1 and 2 show a water-cooled four-cycle internal combustion engine having a dry-type sleeve, but the present invention is not limited to this embodiment.

The vehicle's 4-cycle engine 1 uses an in-line 4-cylinder engine. You. The cylinder block 2 of the four-cycle engine 1 includes a cylinder body 2 a and a sleeve 3, and a piston 4 is provided on the sleeve 3 so as to be able to reciprocate. The reciprocating motion of the piston 4 rotates a crankshaft (not shown) disposed in the crank chamber 7 via the conrod 5. A cylinder head 6 is provided in the cylinder block 2, and is fixed to the cylinder block 2 by a bolt 8. The piston 4 is provided with a piston ring 4b. The cylinder head 6 is provided with a head cover 180.

A combustion chamber 12 is formed by the sleeve 3 of the cylinder block 2, the head 4 a of the piston 4, and the cylinder head 6. A spark plug 86 is attached to the cylinder head 6 so as to face the combustion chamber 12.

An intake passage 13 and an exhaust passage 14 are formed in the cylinder head 6, and a collective intake pipe 15 is connected to the intake passage 13. A collective exhaust pipe 16 is connected to the exhaust passage 14.

The opening of intake passage 13 facing combustion chamber 12 is opened and closed by intake valve 18, and the opening of exhaust passage 14 facing combustion chamber 12 is opened and closed by exhaust valve 19. The camshafts 32 and 33 of the camshafts 32 and 33 are in contact with the tappets 30 and 31 of the intake valve 18 and the exhaust valve 19, respectively. By rotation, the cams 32a and 33a push the intake valve 18 and the exhaust valve 19 via the tapes 30 and 31 to open and close the intake passage 13 and the exhaust passage 14. I do.

A water jacket 20 is formed in the cylinder body 2 a of the cylinder block 2, and a water jacket 21 is formed in the cylinder head 6 in communication with the water jacket 20. This water jacket 2 0, 2 1 The area around the combustion chamber 12 is cooled by cooling water, and the sleeve 3 has a dry structure.

Fig. 3 shows a water-cooled four-stroke internal combustion engine with a wet-type sleeve that cools around the combustion chamber 12 with the cooling water of the water jacket 20 and cools the sleeve 3 directly with the cooling water. It has become. At the lower part of the water jacket 20, a 0 ring 85 is provided between the cylinder body 2a and the sleeve 3 for sealing.

Next, the production of a cylinder block for an internal twist engine will be described with reference to FIG.

A rapidly solidified powder material is formed (step S1), and the rapidly solidified powder material is cold isostatically pressed to form a sleeve material (bilette) (step S2) and vacuum-sintered (step S3). ). Thereafter, heating and hot extruding are performed to form a hollow hollow material and then cooled (step S4). Heat treatment is performed as needed, and the sleeve hollow material is cut and processed (step S5) to form the sleeve 3. The sleeve 3 is wrapped in a cylinder body 2a (step S6), annealed (step S7), plated (step S8), and honed (step S9). For the rapidly solidified powder material in step S1, for example, an ingot of an aluminum alloy containing silicon (Si), iron (Fe) and other components is prepared for an aluminum (A1) base material. This is melted at about 700 ° C or more, then sprayed in a mist and rapidly cooled and solidified at a cooling rate of 100 V / sec or more to obtain a rapidly solidified powder of aluminum alloy ( (Powder metal).

As an aluminum alloy powder material for forming a sleeve material (billette), for example, the primary crystal silicon has an average particle diameter of 20 / zm or less. Below, a rapidly solidified powder of an aluminum alloy containing silicon (S i) of preferably 2 to 10 μm in a range of 15 to 38% by weight is used.

As a rapidly solidified powder of such an aluminum alloy, aluminum (A1) is used as a base material, and silicon (Si) is 15 to 38% by weight, and iron (Fe) is 1.5%. Wt% or less, copper (Cu) 6.8 wt% or less, magnesium (Mg) 0.2 to 2 wt%, manganese (Mn) 1.5 wt% or less, chromium (Cr) 0. Some contain zinc (Zn) in a range of not more than 0.3% by weight and not more than 4% by weight.

Inclusion components of aluminum alloy rapidly solidified powder of 15 to 38% by weight with Si content increased based on 2000 series or 600 series aluminum alloy specified in JIS In the above, silicon (S i) is added to increase wear resistance and seizure resistance by crystallizing hard primary and eutectic silicon grains in the metal structure. Is added to increase the strength at 200 ° C or higher by dispersing and strengthening the metal structure, and copper (Cu) and magnesium (Mg) increase the strength at 200 ° C or lower. It is added in order to increase the content. With respect to the added amount, desired wear resistance, seizure resistance, and necessary strength at high temperatures can be obtained.

In the above-mentioned sleeve material in which the rapidly solidified powder of aluminum alloy is solidified, the dissolved aluminum alloy is sprayed in a mist and solidified by rapid cooling, so that the aluminum alloy powder is flat. The average particle size is about 20 to 100 / zm, and the silicon (S i) contained therein is hardened crystallized in the metal structure of the aluminum alloy that solidifies while powdering. Primary crystal silicon (Si) has an average particle size of 20 / zm or less, preferably 2 to 10 m, and dispersed for each aluminum alloy particle.

In step S2, the rapidly solidified powder of the aluminum alloy is placed in a mold having an opening in one or more directions, and the plunger is inserted into the mold through the opening while bleeding air. While maintaining the mold in a watertight state, a hydrostatic press is applied to the plunger to apply a hydrostatic pressure, and the rapidly solidified powder material is solidified.

In step S3, the pre-solidified rapidly solidified powder material is placed in a sintering mold, and the inside of the mold is evacuated and heated and pressurized to form a denser solid mass with almost no air mixing. You.

In step S4, the solid mass is housed in the extrusion die, heated, extruded from the die portion of the extrusion die into a hollow round bar, that is, a hollow element shape, cut at the cooled portion, and cut into a predetermined length. It is a hollow round bar. In step S4, the parameters in the process are adjusted so that the hardness of the hollow hollow material after extrusion and cooling becomes not less than the mouthwell hardness (HRB) 40.

In step S5, the sleeve material is cut to a length, and the inner and outer shape and the end are processed to form a wrapping sleeve.

In step S6, the sleeve 3 is wrapped around the cylinder main body 2a, and a cylinder die-cast molding that wraps around the sleeve 3 is performed. In this case, the sleeve 3 is housed in a mold, and a part of the inner periphery of the sleeve is supported by a supporting member. Is conducted at high pressure. Then, machining of each part of cylinder block 2 and cylinder bores was performed.

4 o By forming irregularities on the outer peripheral surface of the sleeve before wrapping the sleeve, the sleeve is reliably prevented from coming off even if the tightening force is reduced due to the difference in the coefficient of thermal expansion between the base material and the sleeve during operation. it can. Such irregularities on the outer surface of the sleeve can be used to form fine cracks artificially by adjusting molding conditions such as extrusion speed and temperature when extruding billets. Can be. It is also possible to use a shot blast. In addition to shot blasting, it can be formed by other machining or pickling (etching) of the entire sleeve. Also, instead of using a method such as shot blasting to form irregularities on the outer periphery of the sleeve to improve the bondability with the base material, the sleeve and the base material are joined using low melting point solder to prevent the sleeve from coming off. You may try.

Here, the shot blast means steel balls, carbide beads, stainless steel balls, zinc beads, glass beads with a particle size of 50 to 150 μm, river sand containing a lot of quartz with a slightly larger particle size, etc. Is a projector that projects a workpiece at a projection speed of, for example, 40 to 8 Om / s.

Annealing is performed in step S7. The heat treatment conditions are adjusted so that the hardness of the sleeve 3 after the annealing becomes Rockwell hardness (HRB) 40 or more.

The plating in step S8 is a plating on the inner surface of the sleeve. Basically, a pretreatment consisting of a degreasing treatment, an alkaline etching treatment, and a mixed acid etching treatment, and a base treatment alumite treatment are combined. It consists of five steps of stick processing, and water washing is performed after each step. After the above plating process (step S8), the inner layer of the sleeve is honed by honing (step S9) to reduce the thickness of the plating film to about 5 mm. 0 ^ m, possibly 20 / im ~ 100 μm and the surface roughness of the plating layer is less than 1.0 μm Rz. As a result, the surface of the plating layer can be surely smoothed, the coefficient of friction when sliding the piston 4 and the piston ring 4b can be reduced, and the retention of engine oil can be improved. The lubrication can be improved. Note that Rz is defined in B0601 of the JIS standard.

In the embodiment of the present invention, although the sleeve 3 made of an aluminum alloy is wrapped in a cylinder body 2a made of an aluminum alloy, the sleeve 2 for an internal combustion engine is press-fitted and shrink-fitted. They may be placed.

A conventional extruded material is used for the sleeve base material. The extruded material has a relatively low silicon content, and its thermal expansion coefficient is the same as that of the aluminum material of the surrounding cylinder body. It is equal to or less than that. When the cylinder block is manufactured, the sleeve base material is filled with the aluminum die cast material. Gaps may occur, which may degrade the accuracy of the inner diameter grinding process in the post-process, and the presence of the gaps may partially degrade the thermal conductivity. This leads to deterioration of the shape such as roundness, which leads to an increase in oil consumption and performance degradation.

As described above, forming the sleeve 3 with an aluminum alloy material having a silicon (Si) content of 15 to 38% by weight results in a gap between the sleeve base material and the aluminum material. It is effective to prevent the formation of such a layer.However, in the case of ordinary bodily materials, the primary crystal Si grains become several 10 m or more, so even if an attempt is made to form a plating layer on the surface, the adhesion is poor. During processing In addition to the occasional sticking and peeling, sufficient durability such as sticking and peeling during operation cannot be obtained.

For this reason, the sleeve 3 is formed by coagulating and solidifying an aluminum alloy powder having an average particle diameter of 20 to 100 / zm, thereby forming this silicon (Si) into an average particle diameter of 2 to 100. The primary silicon of zm (S i). Further, the aluminum alloy constituting the sleeve 3 contains 15 to 38% by weight of silicon (Si) as described above, and the linear expansion coefficient of the sleeve 3 is 15 to 22 (20%). 0 ° C) and smaller than the coefficient of linear expansion of the cylinder body 2a (for example, the coefficient of linear expansion of aluminum alloy ADC12 for JIS die casting 20 (at 200 ° C)). However, the coefficient of linear expansion of the sleeve 3 is at least 10% smaller than the coefficient of linear expansion of the cylinder body 2a.

Therefore, when the aluminum alloy sleeve 3 is wrapped in the aluminum alloy cylinder body 2a, the molten metal on the cylinder body 2a side surrounds the outer periphery of the sleeve 3, and the sleeve 3 is heated and thermally expanded. On the other hand, as the cylinder body 2a is gradually cooled after filling, the sleeve 3 is also cooled and thermally contracts, and the molten metal on the cylinder body 2a side contracts when cooling and solidifying, and the temperature further increases. Although heat shrinks as the temperature decreases, it contains 15 to 38% by weight of silicon (Si), and the coefficient of linear expansion of sleeve 3 is at least smaller than the coefficient of linear expansion of cylinder body 2a. 10% smaller value, the sleeve tightening force due to solidification shrinkage on the cylinder body 2a side and heat shrinkage after solidification is not relaxed, and a gap is created between the sleeve 3 and the cylinder body 2a Absent.

In addition, using a rapidly solidified powder solidified extrusion forming material with a chemical composition of silicon alloy (S i) added to an aluminum alloy for the sleeve base material. Forming a hollow round rod, a height of 0.1 to 2 mm, and continuous projections parallel to the length direction by adjusting the extrusion conditions, for example, extrusion speed, temperature, etc., or And uniformly distribute microcracks with a depth of 10 ζ πι ~ 1 ιη ιη on the surface, or microcracks with a depth of 10 / zm to a maximum of 20% of the thickness of the sleeve base material on the surface. By evenly distributing the cracks and leaving protrusions or small cracks on the outer peripheral surface even after processing into the sleeve, the connection with the cylinder body 2a is strengthened and the heat Transmission can be made uniform.

Also, in the operating state, the temperature of the sleeve 3 is lower than the temperature at the time of wrapping (a value close to the melting temperature of the aluminum alloy), but it is 100 ° C to 300 ° C since air cooling and water cooling are performed. 15 to 38% by weight of silicon (Si), and the coefficient of linear expansion of the sleeve 3 is at least 10% smaller than the coefficient of linear expansion of the cylinder body 2a. As a result, the gap between the sleeve 3 and the cylinder body 2a is not generated, the cylindricity and roundness of the inner circumference of the sleeve are maintained, and the heat from the circumferential surface of the sleeve 3 is maintained. Since heat is well transferred to the cylinder body through the metal layer and the inside of the sleeve 3, hot spots are not easily generated, and seizure with the piston 4 can be prevented. After the completion of fabrication (normal temperature condition), a predetermined work is performed, a honing finish is applied, the cylindricity and roundness of the inner circumference of the sleeve 3 are increased, and a crankshaft or a piston is attached to the cylinder block 2. After the assembly of the internal combustion engine is completed by assembling the tongue and fastening the cylinder head 6 with bolts 8 and operating the internal combustion engine, the sleeve 3 thermally expands, and at this time, the cylinder head 6 The cylinder body around the sleeve where the bolts are fastened

While the rigidity around the multiple bolt holes in 2 is increased and resists thermal expansion, The cylinder body 2a, which is the middle part of the bolt hole on the outer periphery of the sleeve, has low resistance to thermal expansion, but contains 15 to 35% by weight of silicon (Si) and has a sleeve 3 The coefficient of linear expansion of the sleeve is at least 10% smaller than the coefficient of linear expansion of the cylinder body 2a, and the sleeve 3 has a small thermal expansion and maintains the cylindricity and roundness of the inner circumference of the sleeve. In addition, the isolation between the combustion chamber 12 and the crank chamber 7 by the bis-toning ring 4b is improved, and it is possible to prevent an increase in oil consumption, deterioration in fuel efficiency due to combustion gas blow-through, and oil deterioration.

Further, not only can a gap be prevented from being formed between the sleeve 3 and the cylinder body 2a, but also the adhesion of the stick can be ensured. This is because in the alkaline etching step, which is a pretreatment for plating, the silicon (Si) particle size is sufficiently small, 2 to 10 / zm, so that precipitation of Ni-P plating is not hindered. It is.

As described above, in the present invention, the aluminum alloy constituting the sleeve 3 contains silicon (Si), and the silicon (Si) has a primary crystal silicon having an average particle size of 2 to 10 lozm. By performing alkali etching on the inner peripheral surface of the sleeve 3, the silicon (S i) on the inner peripheral surface of the sleeve 3 is removed by an all-round leaching process, and irregularities are formed on the inner peripheral surface of the sleeve. Since the silicon (S i) particles are formed and the average particle size is small, fine irregularities can be formed densely, and the bonding area between the inner peripheral surface of the sleeve and the plating layer is increased, thereby further improving the bonding property. It has an anchor effect due to irregularities, and furthermore, the heat transfer area increases due to the increase in the coupling area, the heat of the combustion gas added to the plating layer can be quickly radiated, and the plating layer is separated. Unfortunately. '

Silicon (S i) is added to the aluminum alloy that constitutes the sleeve 3. 15 to 35% by weight, the silicon (S i) content is high and the average particle size of the silicon (S i) particles is small, so that finer irregularities can be densely formed. In addition, the joint area between the inner peripheral surface of the sleeve and the plating layer is increased, and the joint property can be further improved. In other words, the heat from the inner peripheral surface of the sleeve 3 is transmitted well to the cylinder main body through the metal layer and the sleeve 3 main body, so that hot spots are hardly formed on the sleeve 3 surface. It is possible to prevent burn-in with the piston 4.

Further, in the present invention, the sleeve material supporting the plating layer may yield and deteriorate due to the combustion pressure applied through the plating layer, the tension of the piston ring, and the like, and the plating layer may peel from the sleeve material. In addition, the rigidity is increased by tightening the cylinder head, and the thermal expansion during operation is not uniform at each part in the circumferential direction of the sleeve. If the hardness is insufficient, the rigidity is low. Deformation due to thermal expansion in the middle part of the head tightening bolt hole is problematic, but silicon (S i) is added to the aluminum alloy of the sleeve by 15 to 38 weight. % And magnesium (Mg) of 1.8% by weight or less, and the sleeve has a Rockwell hardness (HRB) of 40 to 70 to prevent yield deterioration of the sleeve 3 and improve rigidity. And due to thermal expansion Deformation can and child reduced.

In addition, at least one or more of copper (Cu), manganese (Mn), and zinc (Zn) are contained in the aluminum alloy constituting the sleeve in a total amount of 1.7 to 8.3% by weight. Therefore, it is possible to prevent yielding deterioration of the sleeve, improve rigidity, and reduce deformation due to thermal expansion. Further, when the cylinder block 2 is manufactured, for example, when the sleeve base material is wrapped by the aluminum die cast material, the sleeve base material and the aluminum die cast are solidified in the process of solidifying the aluminum die cast material. Gaps are formed between the objects, which may deteriorate the accuracy of the inner diameter grinding process in the subsequent process.Furthermore, the presence of the gaps partially deteriorates the heat conductivity, so Deterioration of the shape, such as cylindricity and roundness, causes an increase in oil consumption and performance, but the sleeve 3, piston 4, and cylinder body 2a are (S i) is formed of an aluminum alloy, and the ratio of the linear expansion coefficients of the sleeve 3, the piston 4, and the cylinder body 2a is 16 to 17: 17 to 18: 20 to 2 Set to 1. For example, by adjusting the content of silicon (Si), the ratio of the silicon (Si) content of the sleeve 3, the piston 4, and the cylinder body 2a is set to 25:17:12. When the ratio of the linear expansion coefficients of the piston 4, the sleeve 3, and the cylinder body 2a is set to 16:18:20, when the internal combustion engine is operated, the piston 4 accompanying the thermal expansion of the piston 4 It is possible to keep the change of the tongue clearance in an ideal state, thereby reducing the loss and the noise, and reducing the oil consumption while maintaining the output performance. be able to.

In addition, the use of an aluminum alloy material having a silicon (Si) content of 15 to 38% by weight causes a gap between the sleeve base material and the aluminum material. Although it is effective to avoid this, the usual crystalline materials can have primary Si grains of several tens of tm or more, so even if an attempt is made to form a paint layer on the surface, the adhesion is poor. Not only does it cause peeling during machining, but also does not provide sufficient durability, such as peeling during operation. For this reason, the sleeve 3 is formed by agglomerating and solidifying an aluminum alloy powder having an average particle diameter of 20 to 100 μm, so that the silicon (S i) has an average particle diameter of 200 μm or less. Primary crystal silicon (Si). In the alkali etching step, which is a pre-treatment for plating, the silicon (Si) particle size is sufficiently small, not more than 20 / m, so that precipitation of Ni—P plating is not hindered. For this reason, adhesion of the plating can be ensured.

As described above, the aluminum alloy constituting the sleeve 3 contains silicon (Si), and the silicon (Si) is used as primary crystal silicon (Si) having an average particle diameter of 20 urn or less. When the inner peripheral surface of the sleeve 3 is subjected to arc-etching processing, silicon (S i) on the inner peripheral surface of the sleeve is removed by the Al force re-etching processing, and irregularities are formed on the inner peripheral surface of the sleeve. Since the average particle diameter of the silicon (Si) particles is small, fine irregularities can be formed densely, and the bonding area between the inner peripheral surface of the sleeve and the plating layer increases, further improving the bonding performance. Possible, has an anchoring effect due to the unevenness, and furthermore, the heat transfer area increases due to the increase in the coupling area, the heat of the combustion gas added to the plating layer can be quickly radiated, and the plating layer is separated. Hateful.

Also, by adding 15 to 38% by weight of silicon (Si) to the aluminum alloy constituting the sleeve 3, the silicon (Si) content is high and the silicon (Si) particles are increased. Since the average particle diameter is small, finer irregularities can be formed densely, and the bonding area between the inner peripheral surface of the sleeve and the plating layer is increased, so that the bonding property can be further improved.

Also, in particular, the sleeve 3 supporting the plating layer is subjected to the pressurizing and heating conditions during the vacuum sintering in step S3 and the cooling conditions after the powders have not been sufficiently bonded, or the heating and hot conditions in step S4. Temperature environment and extrusion in extrusion By setting the diameter reduction ratio during extrusion, the shape of the extrusion opening of the mold, the cooling conditions after extrusion, or the sleeve temperature control (heating, warming or cooling, etc.) conditions during wrapping, or the annealing conditions, etc. In the wrapped state, the mouth wall hardness (HRB) shall be 40 to 70. As a result, even if the explosion pressure or the tension of the screw pin acts on the sleeve 3 via the metal layer, the metal layer supporting portion of the sleeve 3 does not undergo plastic deformation. Hard to cause delamination. That is, it is possible to prevent the metal layer from falling off and the sleeve 3 from being abnormally worn, which adversely affects the engine durability.

As an example, a rapidly solidified powder solidification extrusion forming material having a chemical composition in which a base material of a JIS 2000 series or JIS 6000 series is added with 25% by weight of silicon (Si) to a sleeving base material. The manufacturing process when using was manufactured by the process of FIG.

This rapidly solidified powder of an aluminum alloy based on the JIS 2000 system and containing silicon (S i) in an amount that gives a hypereutectic composition is based on aluminum (A 1). Among them, silicon (Si) is 15 to 38% by weight, iron (Fe) is 1.5% by weight or less, copper (Cu) is 1.5 to 6.8% by weight, magnesium (Mg) ) Is not more than 1.8% by weight, manganese (Mn) is not more than 0.2 to 1.2% by weight, chromium (Cr) is not more than 0.1% by weight, zinc (Zn) is not more than 0.3% by weight, Titanium (Ti) was set to 0.2% by weight or less.

The rapidly solidified powder of an aluminum alloy based on JIS 600 and added with an amount of silicon (Si) that becomes a hypereutectic composition is based on aluminum (A1). Inside, silicon (S i) is 15 to 38% by weight, iron (F e) is less than 1.0% by weight, and copper (Cu) is 0.4% by weight. % Or less, magnesium (Mg) 0.35 to: 1.5% by weight or less, manganese (Mn) 0.8% by weight or less, chromium (Cr) 0.35% by weight or less, zinc (Zn) 0.25% by weight or less and titanium (Ti) 0.15% by weight or less.

In Example 1, JIS 600-based 6 06 1 — 25 Si solidified solidified powder was used as the extruded material as a sleeve base material. The Ni-P-SiC dispersed composite Wood was given.

Example 2 is a JIS 600-based system of 6 06 1 + 2 to 4 Fe—25 S i quenched solidified powder solidified extruded material used as a sleeve base material, and N i -P-S i C A dispersed composite plating was applied.

In Example 3, JIS 2000 series 20 17 or 202 4—25 S i rapidly solidified powder solidified extruded material was used as a sleeve substrate, and a Ni—P—S i C dispersed composite plating was applied on the inner surface. gave.

In this embodiment, the reduction of the oil consumption is an improvement of the cylinder deformation, and attention was paid to improving the contact of the sleeve after the integration. In order to improve the adhesion of the sleeve, we focused on changing to a sleeve material with a low linear expansion coefficient. And

The physical and mechanical properties of this sleeve material are compared and shown in Table 1.The sleeve has a low linear expansion coefficient of aluminum as the base material and has a hard film formed on the inner surface. The linear expansion coefficient α of the sleeve substrate was reduced compared to the ADC12, an aluminum alloy material of 12Si-3Cu.比率 The ratio of the linear expansion coefficient of the cylinder body ADC12, which is the wrapping material, to 0.85, and the tightening deformation when inserting the sleeve was improved.

Further, the interfacial gap at the time of wrapping is reduced as shown in Table 2 by annealing at 250 ° C. for 1 hour and then cooling. The interface gap between the sleeve and the cylinder body was measured at eight locations in the circumferential direction of the sleeve. In the case of the bore No 4, the mold cooling is stopped as abnormal.

Table 2

界面 When the interfacial gap at the time of wrapping is reduced, as shown in Table 1, the Young's modulus of the liner substrate is improved, the roundness and cylindricity of the cylinder after honing are improved, and the followability of the piston ring is improved. The sealing performance is improved.

In addition, 界面 When the interfacial gap at the time of wrapping is reduced, heat transfer is made uniform and improved, local deformation during operation can be improved, and the circularity and cylindricity of the cylinder after honing are reduced. Improved piston ring followability and sealability, and improved oil consumption.

In Examples 1 to 3, extrusion was performed using a rapidly solidified powder solidified extrusion forming material, and by adjusting the extrusion processing conditions, for example, extrusion speed, temperature, etc., as shown in FIG. On the outer surface of the substrate, continuous protrusions 100 with a height of 0.12 mm parallel to the length direction were formed, and a small crack 101 with a depth of 10 ^ mlmm was formed on the surface. Were distributed in the same manner. Figure 6 shows the relationship between the surface depth of the sleeve and the sleeve strength and interfacial gap.The depth of 10 μτα to 1 mm on the surface indicates that the sleeve strength is high and the interfacial gap is small. This is the optimal range of the depth, and this depth 10 II! By uniformly distributing the minute cracks 101 of about 1 mm, it is possible to strengthen the bonding between the body and the cylinder body 2a and to make the heat transfer uniform.

In addition, the surface has a depth of 10 nm to a maximum of 20% of the thickness of the sleeve base material, and the strength of the sleeve is large, and the interface gap can be reduced. By uniformly distributing microcracks 01 at a depth of 10 m to a maximum of 20% of the thickness of the sleeve base material, the bonding of the solid to the cylinder body 2 a is strengthened. And heat transfer can be made uniform.

In Examples 1 to 3, a Nigel-based dispersion method containing phosphorus and eutectoids was performed at a high speed, and nickel (Ni) -lin (P) -silicon carbide (Si) was used. The dispersion method of C) is performed at high speed, and this Ni-P-SiC dispersion method has the following properties.

When Ni-P-SiC dispersion plating is applied to the inner surface of the sleeve 3, the Ni-P matrix 51 shown in Fig. 7 is applied to the inner surface of the sleeve 3. A plating film 50 containing eutectoid particles 52 of SiC and SiC is formed. An oil pocket 53 composed of a horn is formed on the surface of the mask film 50 for lubrication (Fig. 7 (a)). Further, the sliding of the piston 5 during operation is performed. As shown in Fig. 7 (b), hard silicon carbide (SiC) eutectoid particles 52 remain and Ni-P matrix 51 wears, as shown in Fig. 7 (b). Oil pocket 54 occurs. Therefore, oil lubrication can be favorably performed over a long period of time.

In addition, the relationship between the temperature and the plating hardness is examined for the above-mentioned Ni—P—SiC dispersion plating, Ni—SiC dispersion plating, and hard chrome plating. — P— S i C dispersion method, especially when heat-treated at about 350 ° C, has higher hardness than hard chrome method and does not contain phosphorus (P). Hardness is greatly increased compared to Tsuki. This indicates that the inclusion of phosphorus increases the hardness after heat treatment.

In this example, when the adhesion of the plate was evaluated by a file test, a drilling test, a heating and quenching test, etc., on the plate-shaped test piece, the adhesion was clearly higher than that of the ingot material. It has been confirmed that it has improved. In addition, a durability test of the internal combustion engine was performed, and it was confirmed that the oil consumption was reduced to about 1 Z2 while maintaining the output performance. Shino Ko

Industrial use

As described above, in an internal combustion engine equipped with a cylinder opening in which the sleeve is disposed in the cylinder body, seizure with bistons is prevented, and fuel consumption and oil deterioration are prevented. Was completed. In addition, the sleeve material prevented yield deterioration, improved rigidity, and reduced deformation due to thermal expansion. Further, it is possible to reduce oil consumption while maintaining the output performance of the internal combustion engine.

Claims

The scope of the claims

1. A cylinder bag for an internal combustion engine in which an aluminum alloy sleeve is wrapped in a cylinder body made of an aluminum alloy, wherein the coefficient of linear expansion of the sleeve is smaller than the coefficient of linear expansion of the cylinder body. An internal combustion engine characterized by the following.

2. The internal combustion engine according to claim 1, wherein the sleeve has a coefficient of linear expansion smaller by at least 10% than a coefficient of linear expansion of the cylinder body.

3. The internal combustion engine according to claim 1, wherein the aluminum alloy forming the sleeve contains 15 to 38% by weight of silicon (Si).

4. The internal combustion engine according to claim 3, wherein said silicon (S i) is primary silicon (S i) having an average particle size of 2 to 10 m.

5. The method according to claim 1, wherein the aluminum alloy powder having an average particle diameter of 20 to 100 m is formed by agglomeration and solidification. Internal combustion engine.

6. Equipped with a cylinder socket that is made by placing an aluminum alloy sleeve inside a cylinder body made of aluminum alloy, so that the piston can reciprocate in the cylinder of this cylinder socket. The stored internal combustion engine,

The internal combustion engine according to any one of claims 1 to 5, wherein a linear expansion coefficient of the piston, the sleeve, and the body of the cylinder is set to three <piston <body of the cylinder.

7. The aluminum alloy that forms the sleeve contains 1.8% by weight or less of magnesium (Mg).

The internal combustion engine according to any one of claims 3 to 6, wherein (HRB) is 40 to 70.

8. The aluminum alloy composing the sleeve contains at least one or more of copper (Cu), manganese (Mn), and zinc (Zn) in a total of 1.7 to 8.3% by weight. The internal combustion engine according to claim 7, wherein the internal combustion engine is operated.

9. The internal combustion engine according to any one of claims 5 to 8, wherein the inner peripheral surface of the sleeve is subjected to an alkali etching treatment and then subjected to a plating.

10 0. The outer surface of the base material of the sleeve has a height of 0.1 to 2 mm. A projection parallel to the length direction is formed on the outer surface. The internal combustion engine according to any one of claims 5 to 9, wherein micro cracks having a thickness of 20% are uniformly distributed.