CN110848043A - An improved engine block and method therefor - Google Patents

Abstract

The invention aims to provide an improved engine cylinder block and a method thereof, aiming at the defects of the prior art, the improved engine cylinder block comprises an engine cylinder block and a cylinder sleeve matched with the engine cylinder block, wherein the engine cylinder block is made of an aluminum alloy material, the engine cylinder sleeve is made of cast iron, a first wear-resistant layer is arranged on the inner wall surface of the engine cylinder block, and the first wear-resistant layer is manufactured by using a laser cladding technology.

Description

An improved engine block and method therefor

technical field

The present invention relates to the field of engines, in particular, to an improved engine cylinder block and a method thereof

Background technique

The cylinder blocks of gasoline/diesel engines are usually divided into cast iron and cast aluminum. As we all know, due to the strength of aluminum-based materials, cast iron materials are still used in part of the aluminum cylinder block engine. Usually, cast iron or steel bushings of about 5mm are directly cast into the aluminum engine block blank, and then pass through multiple channels. The mechanical processing process meets the technical indicators required by the design, and produces qualified engine block parts, but the difference in thermal expansion coefficient between cast iron and aluminum alloy will also cause the bushing to be deformed by heat and detach from the inner wall of the aluminum alloy cylinder, thereby forming an air chamber, which is a serious problem. It affects the heat dissipation capacity of the engine, aggravates the wear of the inner wall of the engine and reduces the service life of the engine.

In order to solve the problem that the difference in thermal expansion coefficient between the above-mentioned cast iron and the engine's aluminum alloy matrix will also cause the bushing to be deformed by heat, the latest technology is to use the plasma spraying technology APS or thermal spraying technology. The alloy wear-resistant layer with a thickness of about 300um is sprayed on. The hardness of the coating is higher than that of the traditional cast iron bushing, and the wear resistance is also greatly improved. Moreover, the 1-5% pores formed by the spraying process have the function of oil storage, which promotes lubrication and reduces friction. It solves the problems of increasing the weight and size of the cast iron bushing of the aluminum alloy engine cylinder, as well as the problems of increased fuel consumption and emissions caused by the inconsistency with the thermal expansion of the inner wall of the cylinder. used by the manufacturer. However, there are also problems such as high cost of texturing process, complicated quality control, low utilization rate of spraying materials, low bonding force between engine aluminum substrate and coating, and low spraying yield.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an improved engine block and a method thereof for the deficiencies of the prior art.

The improved engine cylinder block includes an engine cylinder block and a cylinder liner matched with the engine cylinder block, wherein the engine cylinder block is made of aluminum alloy material, the engine cylinder liner is made of cast iron, and the engine cylinder block is made of cast iron. The inner wall surface is provided with a first wear-resistant layer, the first wear-resistant layer is manufactured by laser cladding technology, the thickness of the first wear-resistant layer is 100-250um, and the strength of the first wear-resistant layer is 100-200MPa .

Further, the outer surface of the cylinder liner is provided with a second wear-resistant layer, the second wear-resistant layer is manufactured by laser cladding technology, the thickness of the second wear-resistant layer is 100-150um, and the second wear-resistant layer is The layer strength is 100 to 200 MPa.

Further, the first wear-resistant layer includes a first ceramic wear-resistant layer and a second ceramic wear-resistant layer, and a first aluminum alloy is disposed between the first ceramic wear-resistant layer and the second ceramic wear-resistant layer Wear-resistant layer, the thickness of the first ceramic wear-resistant layer is 60um-120um, the thickness of the first aluminum alloy wear-resistant layer is 10um-50um, and the thickness of the second ceramic wear-resistant layer is 40um-100um.

Further, the second wear-resistant layer includes a second aluminum alloy wear-resistant layer and a third aluminum alloy wear-resistant layer, and between the second aluminum alloy wear-resistant layer and the third aluminum alloy wear-resistant layer is also provided There is a third ceramic wear-resistant layer, the thickness of the second aluminum alloy wear-resistant layer is 10-50um, the thickness of the third ceramic wear-resistant layer is 40-100um, and the thickness of the third aluminum alloy wear-resistant layer is 10-50um.

Further, the thickness of the first ceramic wear-resistant layer is 90um, the thickness of the first aluminum alloy wear-resistant layer is 30um, and the thickness of the second ceramic wear-resistant layer is 70um.

Further, the thickness of the second aluminum alloy wear-resistant layer is 30um, the thickness of the third ceramic wear-resistant layer is 70um, and the thickness of the third aluminum alloy wear-resistant layer is 30um.

A method of improving an engine block, comprising the steps of:

Step 1: Process positioning holes on the bottom of the engine according to the design requirements;

Step 2, processing the cylinder hole of the engine cylinder block based on the processing positioning hole described in step 1, the cylinder hole diameter of the engine cylinder block is 0.25-0.4mm larger than the cylinder hole diameter of the engine cylinder block in the design;

Step 3, cleaning the cylinder bore of the engine cylinder block in step 2 at a temperature of 50-60° C., so that there is no cutting residue on the surface of the cylinder bore of the engine cylinder block;

Step 4, positioning the cylinder in step 3 on the rotary table, so that the axis of the cylinder hole of each cylinder coincides with the rotation centerline of the rotary table;

Step 5: After the axis of the cylinder hole of the cylinder body coincides with the rotation center line of the rotary table in step 4, the rotary table is rotated by 90°, so that the axis of the cylinder hole of the cylinder block is horizontal. direction, and rotate at a rotation speed of 30~800R/min;

Step 6, use the laser cladding nozzle to move at a constant speed along the axis of the cylinder hole of the cylinder described in step 5, the speed is 2000-4000mm/min, and the aluminum alloy or ceramic cladding is evenly clad on the inner wall of the engine cylinder, A wear-resistant layer is formed, the thickness of the wear-resistant layer is 100-250um, and the strength is 100-200MPa.

Further, in step 6, the powder of the coating material is coated on the inner wall surface of the cylinder hole of the engine, and the laser cladding nozzle is moved at a speed of 3000 mm/min using laser remelting or during the laser irradiation process. Under the protection of nitrogen or argon, the coating material is synchronously and continuously fed into and remelted on the inner wall surface of the cylinder bore of the cylinder block of the engine.

Further, the method for improving the engine cylinder block by the laser cladding technology can clad a wear-resistant layer on the outer surface of the cylinder liner.

Compared with the prior art, the method of the present invention has the following remarkable superior effects:

1. The improved engine block of the present invention and its method do not need to carry out high-cost texturing treatment on the surface of the all-aluminum engine cylinder bore. The laser cladding technology has extremely low requirements on the above, the process cost is greatly reduced, and the yield is reduced. Significantly increased.

2. The improved engine cylinder block and the method thereof of the present invention, the engine cylinder bore laser cladding in the coating coating process, generates very little splash, reduces the pollution of the splash on the machined surfaces of the engine, and reduces the splash cleaning process, thereby reducing production costs.

3. The improved engine cylinder block and the method thereof of the present invention, the laser cladding of the engine cylinder hole forms a metallurgical bond between the coating and the substrate, and the bonding strength is high, which reduces the risk of the engine cylinder hole coating falling off.

4. The improved engine block and method of the present invention, the combination of multi-layer wear-resistant layers extends the service life on the premise of enhancing the strength of the wear-resistant layer, and at the same time, the wear-resistant layer with heat insulation function reduces heat losses and also improve the fuel efficiency of the engine.

5. The improved engine cylinder block and the method thereof of the present invention can repair the engine whose cylinder bore is worn, realize the reuse of the engine cylinder block, and reduce environmental pollution.

Description of drawings

FIG. 1 is a schematic structural diagram of the improved engine block according to the present invention.

FIG. 2 is a schematic diagram of the cylinder liner structure of the improved engine block according to the present invention.

Markings in the figure: 1-engine block, 11-first wear-resistant layer, 111-first ceramic wear-resistant layer, 112-first aluminum alloy wear-resistant layer, 113-second ceramic wear-resistant layer 12-cylinder bore; 2 -Cylinder liner, 21- The second wear-resistant layer, 211- The second aluminum alloy wear-resistant layer, 212- The third ceramic wear-resistant layer, 213- The third aluminum alloy wear-resistant layer.

Detailed ways

The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

Embodiment 1: As shown in Figures 1-2, the improved engine block includes an engine block 1 and a cylinder liner 2 matched with the engine block, wherein the engine block 1 uses an aluminum alloy material Production, the engine cylinder liner 2 is made of cast iron material, the inner wall surface of the engine block 1 is provided with a first wear-resistant layer 11, the thickness of the first wear-resistant layer 11 is 100-250um, and the first wear-resistant layer 11 has a thickness of 100-250um. The layer strength is 100 to 200 MPa.

Further, the outer surface of the cylinder liner is provided with a second wear-resistant layer 21, the thickness of the second wear-resistant layer 21 is 100-150um, and the strength of the second wear-resistant layer is 100-200MPa.

Further, the first wear-resistant layer 11 includes a first ceramic wear-resistant layer 111 and a second ceramic wear-resistant layer 113 , and the first ceramic wear-resistant layer 111 and the second ceramic wear-resistant layer 113 are disposed between There is a first aluminum alloy wear-resistant layer 112, which is used as a base surface to improve the bonding strength. The thickness of the first ceramic wear-resistant layer 111 is 60um～120um, and the thickness of the first aluminum alloy wear-resistant layer is 10um～112um. 50um, the thickness of the second ceramic wear-resistant layer is 40um～100um at 113 degrees.

Further, the second wear-resistant layer 21 includes a second aluminum alloy wear-resistant layer 211 and a third aluminum alloy wear-resistant layer 213, and the second aluminum alloy wear-resistant layer 211 and the third aluminum alloy wear-resistant layer A third ceramic wear-resistant layer 212 is also arranged between 213, the thickness of the second aluminum alloy wear-resistant layer 211 is 10um-50um, the thickness of the third ceramic wear-resistant layer 212 is 40um-100um, and the thickness of the third aluminum alloy wear-resistant layer The thickness of 213 is 10-50um, which is used to provide certain protection for the third ceramic wear-resistant layer 212, ensure the heat resistance of the cylinder liner, and provide a base surface for continued cladding and friction resistance.

Further, the thickness of the first ceramic wear-resistant layer 111 is 90 μm, the thickness of the first aluminum alloy wear-resistant layer 112 is 30 μm, and the thickness of the second ceramic wear-resistant layer 113 is 70 μm.

Further, the thickness of the second aluminum alloy wear-resistant layer 211 is 30um, the thickness of the third ceramic wear-resistant layer 212 is 70um, and the thickness of the third aluminum alloy wear-resistant layer 213 is 30um.

Further, the first ceramic wear-resistant layer, the second ceramic wear-resistant layer and the third ceramic wear-resistant layer can also be metal alloy materials such as nickel-based, cobalt-based, iron-based alloys, and tungsten carbide composites.

Further, the cylinder liner can also be an iron-based alloy bushing.

A method for improving engine cylinder block by laser cladding technology, which includes the following steps:

Step 1: Process positioning holes on the bottom of the engine according to the design requirements;

Step 2, processing the cylinder hole of the engine cylinder block based on the processing positioning hole described in step 1, the cylinder hole diameter of the engine cylinder block is 0.25-0.4mm larger than the cylinder hole diameter of the engine cylinder block in the design;

Step 3, cleaning the cylinder bore of the engine cylinder block in step 2 at a temperature of 50-60° C., so that there is no cutting residue on the surface of the cylinder bore of the engine cylinder block;

Step 4, positioning the cylinder in step 3 on the rotary table, so that the axis of the cylinder hole of each cylinder coincides with the rotation centerline of the rotary table;

Step 5: After the axis of the cylinder hole of the cylinder body coincides with the rotation center line of the rotary table in step 4, the rotary table is rotated by 90°, so that the axis of the cylinder hole of the cylinder block is horizontal. direction, and rotate at a rotation speed of 30~800R/min;

Step 6, use the laser cladding nozzle to move at a constant speed along the axis of the cylinder bore of the cylinder block described in step 5, at a speed of 2000-4000 mm/min, to uniformly clad the aluminum alloy or ceramic cladding on the inner wall of the engine cylinder.

Further, in step 6, the powder of the coating material is coated on the inner wall surface of the cylinder bore of the engine, and the laser cladding nozzle is moved at a speed of 3000 mm/min using laser remelting or during the laser irradiation process. Under the protection of nitrogen or argon, the coating material is synchronously and continuously fed into and remelted on the inner wall surface of the cylinder bore of the cylinder block of the engine.

Further, the thickness of the wear-resistant layer is 100-250um, and the strength is 100-200MPa.

Further, the method of forming the wear-resistant layer on the inner wall surface of the cylinder bore of the cylinder block by the laser cladding technology can also clad the wear-resistant layer on the outer surface of the cylinder liner.

Further, the cladding material is preheated before cladding, which can reduce cladding cracks.

Further, the cladding material can also be filamentous.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. All within the spirit and principles of the present invention, Any modification, equivalent replacement, improvement, etc. made, such as improving the rotation of the engine cylinder block to the rotation of the laser cladding gun body itself, to realize the laser cladding of the inner wall of the engine cylinder hole, shall be included in the protection scope of the claims of the present invention. Inside.

Claims (9)

1. The utility model provides a modified engine cylinder body, including engine cylinder body and with engine cylinder body complex cylinder liner, its characterized in that, engine cylinder body uses aluminum alloy material preparation, engine cylinder liner uses cast iron preparation, engine cylinder body inner wall surface is provided with first wearing layer, first wearing layer uses laser cladding technique to make, first wearing layer thickness is 100 ~ 250um, first wearing layer intensity is 100 ~ 200 MPa.

2. The improved engine cylinder block as recited in claim 1, wherein a second wear layer is disposed on an outer surface of the cylinder sleeve, the second wear layer is manufactured by a laser cladding technology, a thickness of the second wear layer is 100-150 μm, and a strength of the second wear layer is 100-200 MPa.

3. The improved engine cylinder block according to claim 1, wherein the first wear layer comprises a first ceramic wear layer and a second ceramic wear layer, a first aluminum alloy wear layer is disposed between the first ceramic wear layer and the second ceramic wear layer, the thickness of the first ceramic wear layer is 60um to 120um, the thickness of the first aluminum alloy wear layer is 10um to 50um, and the thickness of the second ceramic wear layer is 40um to 100 um.

4. The improved engine cylinder block according to claim 2, wherein the second wear layer comprises a second aluminum alloy wear layer and a third aluminum alloy wear layer, a third ceramic wear layer is further disposed between the second aluminum alloy wear layer and the third aluminum alloy wear layer, the thickness of the second aluminum alloy wear layer is 10-50 um, the thickness of the third ceramic wear layer is 40-100 um, and the thickness of the third aluminum alloy wear layer is 10-50 um.

5. The improved engine block according to claim 3, wherein the first ceramic wear layer is 90um thick, the first aluminum alloy wear layer is 30um thick, and the second ceramic wear layer is 70um thick.

6. The improved engine block of claim 4, wherein the second aluminum alloy wear layer is 30um thick, the third ceramic wear layer is 70um thick, and the third aluminum alloy wear layer is 30um thick.

7. A method of retrofitting an engine block, comprising the steps of:

step 1, processing a positioning hole on the bottom surface of an engine according to design requirements;

step 2, processing a cylinder hole of the engine cylinder block by taking the processing positioning hole in the step 1 as a reference, wherein the diameter of the cylinder hole of the engine cylinder block is 0.25-0.4 mm larger than that of the cylinder hole of the engine cylinder block in design;

step 3, cleaning the cylinder hole of the engine cylinder block in the step 2 at the temperature of 50-60 ℃ to ensure that no cutting residue exists on the surface of the cylinder hole of the engine cylinder block;

step 4, positioning the cylinder bodies in the step 3 on a rotary worktable, and enabling the axis of the cylinder hole of each cylinder body to be superposed with the rotary central line of the rotary worktable;

step 5, after the axis of the cylinder hole of the cylinder body is overlapped with the rotation center line of the rotary worktable in the step 4, the rotary worktable rotates for 90 degrees, so that the axis of the cylinder hole of the cylinder body is in the horizontal direction and rotates at the rotation speed of 30-800R/min;

and 6, moving the laser cladding nozzle at a constant speed of 2000-4000 mm/min along the axis of the cylinder hole of the cylinder body in the step 5, and cladding the aluminum alloy or the ceramic uniformly on the inner wall of the engine cylinder body to form a wear-resistant layer, wherein the thickness of the wear-resistant layer is 100-250 micrometers, and the strength of the wear-resistant layer is 100-200 MPa.

8. The method for improving an engine block by the laser cladding technology according to claim 7, characterized in that powder of coating material is coated on the inner wall surface of the cylinder hole of the engine in step 6, the laser cladding nozzle is moved at 3000mm/min by laser remelting or during laser irradiation, and the coating material is synchronously and continuously fed and remelted on the inner wall surface of the cylinder hole of the engine block under the protection of nitrogen or argon.

9. The method for improving the engine block by the laser cladding technology as claimed in claim 7, wherein the method for improving the engine block by the laser cladding technology can weld the wear-resistant layer on the outer surface of the cylinder liner.

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