阅读说明：本技术 高强度铝合金集成排气缸盖及其倾转式铸造浇注成型工艺 (High-strength aluminum alloy integrated exhaust cylinder cover and tilting type casting and casting molding process thereof ) 是由 黄磊 廖飞虎 王飞 刘建宏 何煊 冯波 韩瑞雷 于 2020-04-30 设计创作，主要内容包括：一种高强度铝合金集成排气缸盖及其倾转式铸造浇注成型工艺,在其缸盖本体的顶部、并在火花塞安装孔上设有冒口,在所述冒口下通过内部冒口依次与螺栓柱、挺杆台相接,在所述冒口的进料口部、并对应于内部冒口的上方处设有截流口；开始90度倾转过程中,铝液在较低的高度平稳地进入金属模具的集成排气腔,确保铝液前沿的氧化膜不会破裂,减少毛坯夹渣及气孔风险,有利于从铸件底部燃烧室到火花塞安装孔顶部的顺序凝固方式成形。本发明提高了缸盖的抗拉强度、屈服强度、延伸率等整体性能。此铸造工艺在质量水平、生产效率、铸件机械性能上位于领先水平,符合高质量、高效率、高性能的总体要求。(A high-strength aluminum alloy integrated exhaust cylinder cover and a tilting casting and casting molding process thereof are disclosed, wherein a dead head is arranged on the top of a cylinder cover body and a spark plug mounting hole, a bolt column and a tappet platform are sequentially connected below the dead head through an internal dead head, and a cutoff port is arranged at a feed port part of the dead head and above the dead head corresponding to the internal dead head; in the process of 90-degree tilting, the aluminum liquid enters the integrated exhaust cavity of the metal mold stably at a lower height, so that an oxide film on the front edge of the aluminum liquid is prevented from breaking, the risk of slag inclusion and air holes of a blank is reduced, and the sequential solidification mode from a casting bottom combustion chamber to the top of a spark plug mounting hole is facilitated to form. The invention improves the overall performances of the cylinder cover, such as tensile strength, yield strength, elongation percentage and the like. The casting process is in the leading level on the quality level, the production efficiency and the casting mechanical property, and meets the overall requirements of high quality, high efficiency and high performance.)

1. High strength aluminum alloy integration bank cylinder cap, including cylinder cap body, camshaft mounting hole and tappet platform, spark plug mounting hole, glib mounting hole, combustion chamber, this internal intake and exhaust way, upper and lower water jacket, oil duct, its characterized in that of being equipped with of this cylinder cap: the top of cylinder cap body is equipped with the rising head on the spark plug mounting hole meet with bolt post, tappet platform in proper order through inside rising head under the rising head the feed inlet portion of rising head is equipped with the cut-off mouth corresponding to the top of inside rising head.

2. The high-strength aluminum alloy integrated row cylinder head as set forth in claim 1, wherein: and a water cooling insert is arranged at the side edge of the air inlet and outlet channel of the cylinder cover body.

3. The high-strength aluminum alloy integrated row cylinder head as set forth in claim 1 or 2, wherein: and clamping platforms are arranged on the two outer sides of the riser, and the top of the riser is provided with a riser lowest height scale mark.

4. The tilt casting molding process for a high-strength aluminum alloy integrated bank cylinder head according to claim 1, wherein: before 90-degree tilting feeding, the top of the metal mold and a feeding port part corresponding to a riser at the top of a cylinder cover casting are butted with a sprue cup, and the height of the aluminum liquid level in the sprue cup is positioned at the root part of the riser; in the process of starting 90-degree tilting, aluminum liquid stably enters an integrated exhaust cavity of a metal mold at a lower height, so that an oxide film at the front edge of the aluminum liquid is prevented from breaking, the risks of slag inclusion and air holes of a blank are reduced, the rejection rate of the blank of a casting is reduced, a cutoff port is arranged at a feed port part of a riser, and the liquid surface oxide film of a sprue cup is prevented from entering a cavity of the metal mold in advance and floating on the top of the riser; the internal riser below the riser is connected with the bolt column and the tappet platform, so that shrinkage porosity of the internal riser is prevented, and the surrounding tappet platforms are fed; and a water cooling insert is arranged in the exhaust and feeding module of the metal die and at the side edge corresponding to the air inlet and exhaust channel of the cylinder cover body.

5. The tilt casting molding process according to claim 4, wherein: the wall thickness of the exhaust side cover edge of the cylinder head body is ensured to be 4.5-5.5mm in the design stage of the cylinder head body, and the wall thickness of the exhaust side cover edge is subjected to positive deviation in casting; the wall thickness of the air inlet side cover edge of the cylinder head body is ensured to be 5.0-5.5mm in the design stage of the cylinder head body, and the wall thickness of the air inlet side cover edge is positively deviated in the casting process.

Technical Field

The invention relates to the field of automobile engines, in particular to an aluminum alloy cylinder cover and a casting and casting molding process thereof.

Background

At present, for the aluminum alloy integrated row cylinder cover with the outline of 512mm multiplied by 314mm multiplied by 141mm, the upper layer water channel and the lower layer water channel, the structure of the water channel core is complex and slender, and a long and narrow thin wall is arranged between the water channel and the exhaust channel, which brings technical challenges to the core manufacturing and the casting molding process. The gravity bottom pouring type casting process adopting the metal mold has the following defects: feeding from the bottom of the casting (a combustion chamber) is not beneficial to solidification from the bottom of the casting to the top (a riser), and the yield of the process is about 12 percent lower when the volume of the riser is increased; the solidification rate is slow when the temperature is too high due to feeding from the bottom of the casting, and the requirements of the mechanical performance of the product and the SDAS of a combustion chamber are difficult to meet; the pouring gate is arranged, so that the metal mold is huge in structure, aluminum is easy to leak during pouring, the manufacturing and maintenance cost is high, the curing time is long, the production efficiency is low, casting defects such as slag holes and exposure after processing are easy to generate, and the casting comprehensive material waste can be generally controlled within 5%. The gravity top-pouring casting process adopting the metal mold has the following defects: the inlet gate of the aluminum liquid is positioned at the cover edge at the top of the casting, when a metal mold cavity is filled, the aluminum liquid flows unstably due to overlarge drop height, so that the phenomena of splashing, sand washing and gas entrainment are generated, the aluminum liquid is easily oxidized, secondary oxidation slag inclusion in the casting is formed, the gate corresponds to the lower surface oxidation flow mark of the casting, and the large air hole is generated at the periphery of the gate, so that the casting quality of the casting in the casting process is difficult to control. The low-pressure casting process adopting the metal mold has the following defects: the inlet gates are generally arranged at the periphery of the combustion chamber at the bottom of the casting, so that the solidification rate is very low, and the requirements of the mechanical performance of the product and the SDAS of the combustion chamber are difficult to meet; the cavity of the water channel formed under low pressure is easy to be stuck with sand and is difficult to clean; gas generated after the sand core is heated in the closed die cavity is not easy to discharge, so that internal air holes of the casting are formed; the wall thickness variation of the joint of the spark plug mounting hole and the oil plate is large, and the joint is far away from a casting bottom casting head, so that the casting stress is large during solidification, and cracks are often generated after heat treatment, so that the quality of the cylinder cover is difficult to control by the casting process.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides the high-strength aluminum alloy integrated exhaust cylinder cover and the tilting casting and casting molding process thereof, which have simple structure and simple and direct process, stably enter a metal mold cavity at a low position by using a tilting aluminum liquid mode, and avoid the risks of secondary oxidation slag inclusion and pores; feeding from a riser at the top of the cylinder cover is beneficial to solidification of castings from bottom to top.

In order to achieve the purpose, the invention is realized by the following technical scheme: the high-strength aluminum alloy integrated row cylinder cover comprises a cylinder cover body, a camshaft mounting hole, a tappet platform, a spark plug mounting hole, a nozzle mounting hole and a combustion chamber, wherein an air inlet and exhaust channel, an upper water jacket, a lower water jacket and an oil channel are arranged in the cylinder cover body, a riser is arranged at the top of the cylinder cover body and on the spark plug mounting hole, the lower part of the riser is sequentially connected with a bolt column and the tappet platform through an internal riser, and a flow intercepting port is arranged at a feed port part of the riser and above the riser corresponding to the internal riser.

And a water cooling insert is arranged at the side edge of the air inlet and outlet channel of the cylinder cover body. And clamping platforms are arranged on the two outer sides of the riser, and the top of the riser is provided with a riser lowest height scale mark.

The tilting casting and casting molding process adopted by the high-strength aluminum alloy integrated row cylinder cover comprises the following steps: before 90-degree tilting feeding, the top of the metal mold and a feeding port part corresponding to a riser at the top of a cylinder cover casting are butted with a sprue cup, and the height of the aluminum liquid level in the sprue cup is positioned at the root part of the riser; in the process of starting 90-degree tilting, aluminum liquid stably enters an integrated exhaust cavity of a metal mold at a lower height, so that an oxide film at the front edge of the aluminum liquid is prevented from breaking, the risks of slag inclusion and air holes of a blank are reduced, the rejection rate of the blank of a casting is reduced, a cutoff port is arranged at a feed port part of a riser, and the liquid surface oxide film of a sprue cup is prevented from entering a cavity of the metal mold in advance and floating on the top of the riser; the internal riser below the riser is connected with the bolt column and the tappet platform, so that shrinkage porosity of the internal riser is prevented, and the surrounding tappet platforms are fed; and a water cooling insert is arranged in the exhaust and feeding module of the metal die and at the side edge corresponding to the air inlet and exhaust channel of the cylinder cover body.

The wall thickness of the exhaust side cover edge of the cylinder head body is ensured to be 4.5-5.5mm in the design stage of the cylinder head body, and the wall thickness of the exhaust side cover edge is subjected to positive deviation in casting; the wall thickness of the air inlet side cover edge of the cylinder head body is ensured to be 5.0-5.5mm in the design stage of the cylinder head body, and the wall thickness of the air inlet side cover edge is positively deviated in the casting process.

After the invention is adopted, feeding is carried out from the riser of the cylinder cover, which is beneficial to forming from a combustion chamber at the bottom of a casting to the top of a spark plug mounting hole in a sequential solidification mode, and the internal riser is connected with a bolt column and a tappet platform, so that effective feeding can be carried out, and the product performance can meet the requirement. The water-cooling insert is arranged in the exhaust feeding module, so that the 17kg blank can be stably produced for a long time when the solidification time is 250S in batch continuous production, and the advantage of high-efficiency production of large castings is embodied. The comprehensive casting waste rate is controlled within 2.3 percent. As the performance requirements of the implementation of the national six on the cylinder cover are improved, the tensile strength is 280Mpa, the yield strength is 220Mpa, the elongation is more than or equal to 4 percent, and the SDAS (secondary dendritic spacing) of a combustion chamber is less than or equal to 25 mu m; the performance requirement is improved by more than 15 percent compared with the original overall performance requirement. The casting process is in the leading level in the field of casting of the aluminum alloy integrated exhaust cylinder cover on the aspects of quality level, production efficiency and casting mechanical property, and meets the overall requirements of high quality, high efficiency and high performance.

Drawings

The invention is further described with reference to the following figures and detailed description.

FIG. 1 is a schematic structural view of a high-strength aluminum alloy integrated bank cylinder head according to the present invention.

Fig. 2 is a schematic structural view (before 90 degrees tilting) of the butt joint of the cylinder head body and the sprue cup of the invention.

Fig. 3 is a schematic structural view (after 90 degrees tilting) of the butt joint of the cylinder head body and the sprue cup of the invention.

Fig. 4 is a schematic structural view (in feeder-fed state, partial section) of the present invention.

FIG. 5 is a schematic view (side view) of the structure of the present invention connected to a water-cooled insert.

Detailed Description

As shown in fig. 1 to 4, the high strength aluminum alloy integrated row cylinder head of the present invention includes a cylinder head body 1, a (double overhead) camshaft mounting hole 15 and a tappet platform 16 (located in the middle of the cylinder head body), a (direct) spark plug mounting hole 18 (located in the upper portion of the cylinder head body), a (direct) spray nozzle mounting hole 22, a combustion chamber 13 (located in the bottom of the cylinder head body), an intake and exhaust duct 14, an upper and lower water jackets 21, a (double high pressure) oil duct 20 (and a tappet) are provided in the cylinder head body 1, a riser 2 is provided on the spark plug mounting hole 18 at the top of the cylinder head body 1, a bolt column 17 (boss shape) and a tappet platform 16 are connected to the lower portion of the riser 2 through an internal riser 10 in sequence, and a shut-off port 19 is provided at a feed port portion 9 (for butt-joint with a sprue cup 5) of the riser 2 and.

As shown in fig. 5, a water-cooled insert 12 (which is connected to a water cooler) is provided at the side of the intake and exhaust duct 14 of the cylinder head body 1 (corresponding to the inside of the exhaust gas feed block 23 of the metal mold used in the cast molding process). As shown in fig. 1, clamping platforms 4 are installed on the outer two sides of the riser 2, and are used for grabbing intelligent and automatic poured workpieces (cylinder cover castings). The top of rising head 2 is equipped with the minimum height scale mark 3 of rising head, realizes the automatic intelligent control who ladles out the aluminium volume.

The 90-degree tilting casting and casting molding process adopted by the high-strength aluminum alloy integrated row cylinder cover comprises the following steps: the method comprises the step of introducing aluminum alloy liquid into a pouring cup 5 of a metal mold for forming an aluminum alloy cylinder cover, wherein the pouring cup is arranged above the exhaust side of the metal mold. As shown in fig. 2 and 3, before the feeding is performed by tilting at 90 degrees, the top of the metal mold and a feeding port 9 of the riser 2 corresponding to the top of the cylinder head casting are butted with a sprue cup 5, and the liquid level of aluminum in the sprue cup 5 is at the root of the riser 2; in the process of starting 90-degree tilting (the tilting angle is changed from 0 degree to 90 degrees), the aluminum liquid stably enters the integrated exhaust cavity 7 of the metal mold at a lower height (namely, the fall is smaller), so that the oxide film at the front edge 6 of the aluminum liquid is prevented from breaking, the risk of slag inclusion and air holes of the blank is reduced, and the rejection rate of the casting blank is reduced.

As shown in fig. 2, 3 and 4, a shut-off port 19 (20-25 mm in width, preferably 23mm in width) is provided at the feed port portion 9 of the riser 2 to prevent the liquid surface oxide film of the tundish 5 from entering the cavity of the metal mold in advance and floating on the top of the riser. In order to prevent the shrinkage porosity of the thermal node of the integrated exhaust flange of the cylinder head, the wall thickness of the exhaust side cover edge 8 of the cylinder head body 1 is ensured to be 4.5-5.5mm (the wall thickness is preferably 5.0 mm) in the design stage, and the wall thickness of the exhaust side cover edge is positively deviated in the casting process; the internal riser 10 below the riser 2 is connected with a bolt column (phi 25 multiplied by 28mm) and a tappet platform to prevent shrinkage porosity and simultaneously feed the surrounding tappet platform; in order to prevent the shrinkage porosity of the high-pressure oil passage of the cylinder head and the hot section of the tappet thereof, the wall thickness of the air inlet side cover edge 11 of the cylinder head body 1 is ensured to be 5.0-5.5mm (wherein the wall thickness is 5.0mm is preferred), and the wall thickness of the air inlet side cover edge is positively deviated during casting. As shown in fig. 5, a water-cooled insert 12 (corresponding to the side of the intake and exhaust duct of the cylinder head body) is arranged in the exhaust and feeding module 23 of the metal mold, the width of a riser is limited to 23mm, and the temperature is ensured to be below 450 ℃ when the mold is opened. Therefore, the requirement of batch continuous production of 17kg cylinder cover blanks is met, the curing time is 250S, the cylinder cover blanks can be stably produced for a long time, and the advantage of high-efficiency production of breakthrough large castings is embodied.

The casting and casting molding process has the advantages that: feeding is carried out from a riser of a cylinder cover, a water cooling mechanism is more favorably arranged independently from a combustion chamber at the bottom of the cylinder cover (casting), the solidification rate is increased, and the product is molded in a successive layer sequential solidification mode from the combustion chamber at the bottom to a spark plug mounting hole and the top of the riser, so that the product performance can meet the relevant high requirement.