阅读说明：本技术 一种高强度压铸铝合金、发动机壳体及其制造方法 (High-strength die-casting aluminum alloy, engine shell and manufacturing method of engine shell ) 是由 金华君 章晓海 于 2019-12-09 设计创作，主要内容包括：本发明公开了一种高强度压铸铝合金、发动机壳体及其制造方法,涉及压铸铝合金技术领域,其技术方案要点包括如下质量百分比的组分：Si：10-11%；Cu：1.8-2%；Fe：0.8-0.9%；Zn：0.3-0.5%；Mn：0.1-0.2%；Mg：0.2-0.3%；Ni：0.04-0.06%；Ti：0.02-0.06%；Pb：0.03-0.05%；Sn：0.012-0.02%；Ca：0.12-0.16%；YbCl<Sub>3</Sub>：2-8%；余量为Al。本发明具有通过对各组分采用适应比例,获得强度高且达到轻量化的目的的铝合金材料,且该铝合金适于车辆部件铸造使用,助于车身自重的降低,提升车辆的燃油经济性；通过该铝合金在相应的制备方法下制造具有轻量化以及高强度特性的发动机壳体；且通过薄铝层在空气中氧化后于发动机壳体的外表面形成一层致密的氧化层,使得该发动机壳体具有高强度的特性；使得发动机壳体具有良好的结构强度的效果。(The invention discloses a high-strength die-casting aluminum alloy, an engine shell and a manufacturing method thereof, relating to the technical field of die-casting aluminum alloys, and the key points of the technical scheme are that the high-strength die-casting aluminum alloy comprises the following components in percentage by mass: si: 10 to 11 percent; cu: 1.8 to 2 percent; fe: 0.8-0.9%; zn: 0.3 to 0.5 percent; mn: 0.1 to 0.2 percent; mg: 0.2 to 0.3 percent; ni: 0.04-0.06%; ti: 0.02-0.06%; pb: 0.03-0.05%; sn: 0.012-0.02%; ca: 0.12 to 0.16 percent; YbCl 3 : 2 to 8 percent; the balance being Al.The aluminum alloy material which is high in strength and achieves the purpose of light weight is obtained by adopting the adaptive proportion of the components, and the aluminum alloy is suitable for casting vehicle parts, contributes to reducing the self weight of a vehicle body and improves the fuel economy of the vehicle; manufacturing an engine housing having light weight and high strength characteristics by the aluminum alloy under a corresponding manufacturing method; a compact oxide layer is formed on the outer surface of the engine shell after the thin aluminum layer is oxidized in the air, so that the engine shell has the characteristic of high strength; the engine housing has good structural strength.)

1. The high-strength die-casting aluminum alloy is characterized by comprising the following components in percentage by mass: si: 10 to 11 percent; cu: 1.8 to 2 percent; fe: 0.8-0.9%; zn: 0.3 to 0.5 percent; mn: 0.1-0.2%；Mg：0.2-0.3%；Ni：0.04-0.06%；Ti：0.02-0.06%；Pb：0.03-0.05%；Sn：0.012-0.02%；Ca：0.12-0.16%；YbCl₃: 2 to 8 percent; the balance being Al.

2. An engine housing, characterized in that: made of an aluminium alloy according to claim 1, the outside of the engine housing being plated with a thin aluminium layer.

3. A method of manufacturing an engine housing, comprising the steps of:

step 1, according to the mass percentage, 10 to 11 percent of Si, 1.8 to 2 percent of Cu, 0.8 to 0.9 percent of Fe, 0.3 to 0.5 percent of Zn, 0.1 to 0.2 percent of Mn, 0.2 to 0.3 percent of Mg, 0.04 to 0.06 percent of Ni, 0.02 to 0.06 percent of Ti, 0.03 to 0.05 percent of Pb, 0.012 to 0.02 percent of Sn, 0.12 to 0.16 percent of Ca and 2 to 8 percent of YbCl₃Adding the Al used as the balance into a mixer, and uniformly mixing to obtain a raw material mixture;

step 2, adding the raw material mixture into a primary graphite crucible clamp, controlling the temperature to be 720 plus 740 ℃, and dissolving the raw material mixture under the protection of nitrogen to form an aluminum alloy molten liquid;

step 3, preheating a casting mold in a casting machine to 220 ℃, introducing an aluminum alloy melt into the casting mold of the casting machine for casting, and cooling to obtain a casting blank;

step 4, heating the casting blank to 600 ℃, quenching under the quenching liquid, cooling at normal temperature, and then keeping the temperature at 220 ℃ for 2h for tempering;

step 5, naturally cooling the tempered casting blank, sequentially performing deburring, shot blasting, side leakage and carbonization cleaning, and drying to obtain a finished product of the engine shell;

and 6, plating an aluminum layer outside the finished product engine shell, wherein the thickness of the aluminum layer is less than 1 wire.

4. A method of manufacturing an engine case according to claim 3, characterized in that: in the step 5, a suspension type shot blasting machine is adopted in the shot blasting process, casting blanks are subjected to suspension and blasting treatment, and the shot blasting is performed by using 0.2mm stainless steel shots.

5. A method of manufacturing an engine case according to claim 3, characterized in that: in step 5, the carbonization cleaning comprises vacuum cleaning, degassing cleaning and steam cleaning which are sequentially carried out.

6. A method of manufacturing an engine case according to claim 3, characterized in that: in step 5, the set temperature of the carbonization cleaning is 180-220 ℃.

7. A method of manufacturing an engine case according to claim 3, characterized in that: in the step 4, the quenching liquid comprises the following components in parts by weight: 80 parts of water, 12 parts of polyoxyethylene glycol, 3 parts of ethylene glycol, 3 parts of sodium benzoate and 2 parts of polyether.

8. The manufacturing method of an engine case according to claim 7, characterized in that: the polyether comprises propylene oxide and tetrahydrofuran in a weight ratio of 1: 1.

Technical Field

The invention relates to the technical field of die-casting aluminum alloy, in particular to high-strength die-casting aluminum alloy, an engine shell and a manufacturing method thereof.

Background

An engine is a machine that can convert other forms of energy into mechanical energy. In order to effectively reduce the weight of the entire vehicle, casting of the engine case is currently being performed gradually using aluminum alloy instead of gray cast iron.

Chinese patent with publication number CN110195176A discloses a high-strength and high-toughness die-casting aluminum alloy and a preparation method thereof, which is characterized by comprising the following components in percentage by mass: si9-11.5%, Cu2-4%, Ni0.2-0.5%, Mg0.2-0.5%, Ti0.1-0.5%, Fe0.5-1.3%, Mn <0.5%, Sr0.02-0.3%, SiC2-5%, Sm0.03-0.2%, and the balance of aluminum.

However, the engine case forged by the die-casting aluminum alloy and the preparation method thereof has poor bonding property of each component in the die-casting process, and thus, the generation of a grain coarsening phenomenon is caused, that is, the eutectic structure is transformed to a coarse and continuous honeycomb structure, and the structural strength of the engine case is influenced, which needs to be improved.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a high-strength die-casting aluminum alloy which has the effect of effectively improving the structural strength of an aluminum alloy die-casting.

In order to achieve the purpose, the invention provides the following technical scheme:

a high-strength die-casting aluminum alloy comprises the following components in percentage by mass: si: 10 to 11 percent; cu: 1.8 to 2 percent; fe: 0.8-0.9%; zn: 0.3 to 0.5 percent; mn: 0.1 to 0.2 percent; mg: 0.2 to 0.3 percent; ni: 0.04-0.06%; ti: 0.02-0.06%; pb: 0.03-0.05%; sn: 0.012-0.02%; ca: 0.12 to 0.16 percent; YbCl₃: 2 to 8 percent; the balance being Al.

The invention also provides an engine housing made of the aluminium alloy of claim 1, the outside of which is plated with a thin aluminium layer.

The invention also provides a manufacturing method of the engine shell, which comprises the following steps:

step 1, mixing the raw materials according to mass percent10-11% of Si, 1.8-2% of Cu, 0.8-0.9% of Fe, 0.3-0.5% of Zn, 0.1-0.2% of Mn, 0.2-0.3% of Mg, 0.04-0.06% of Ni, 0.02-0.06% of Ti, 0.03-0.05% of Pb, 0.012-0.02% of Sn, 0.12-0.16% of Ca and 2-8% of YbCl₃Adding the Al used as the balance into a mixer, and uniformly mixing to obtain a raw material mixture;

step 2, adding the raw material mixture into a primary graphite crucible clamp, controlling the temperature to be 720 plus 740 ℃, and dissolving the raw material mixture under the protection of nitrogen to form an aluminum alloy molten liquid;

step 3, preheating a casting mold in a casting machine to 220 ℃, introducing an aluminum alloy melt into the casting mold of the casting machine for casting, and cooling to obtain a casting blank;

step 4, heating the casting blank to 600 ℃, quenching under the quenching liquid, cooling at normal temperature, and then keeping the temperature at 220 ℃ for 2h for tempering;

step 5, naturally cooling the tempered casting blank, sequentially performing deburring, shot blasting, side leakage and carbonization cleaning, and drying to obtain a finished product of the engine shell;

and 6, plating an aluminum layer outside the finished product engine shell, wherein the thickness of the aluminum layer is less than 1 wire.

The invention is further configured to: in the step 5, a suspension type shot blasting machine is adopted in the shot blasting process, casting blanks are subjected to suspension and blasting treatment, and the shot blasting is performed by using 0.2mm stainless steel shots.

The invention is further configured to: in step 5, the carbonization cleaning comprises vacuum cleaning, degassing cleaning and steam cleaning which are sequentially carried out.

The invention is further configured to: in step 5, the set temperature of the carbonization cleaning is 180-220 ℃.

The invention is further configured to: in the step 4, the quenching liquid comprises the following components in parts by weight: 80 parts of water, 12 parts of polyoxyethylene glycol, 3 parts of ethylene glycol, 3 parts of sodium benzoate and 2 parts of polyether.

The invention is further configured to: the polyether comprises propylene oxide and tetrahydrofuran in a weight ratio of 1: 1.

In conclusion, the invention has the following beneficial effects:

1. the obtained aluminum alloy has high strength, achieves the aim of light weight, is suitable for casting vehicle parts, contributes to reducing the self weight of a vehicle body, and improves the fuel economy of the vehicle;

2. an engine case made of the aluminum alloy has characteristics of light weight and high strength; a compact oxide layer is formed on the outer surface of the engine shell after the thin aluminum layer is oxidized in the air, so that the engine shell has the characteristic of high strength;

3. by adopting the adaptive proportion of the components and the corresponding preparation method, the engine shell with good structural strength and corrosion resistance is obtained.

Detailed Description