KR20100102301A

KR20100102301A - Wear-resistant aluminum alloy for vehicles

Info

Publication number: KR20100102301A
Application number: KR1020090020609A
Authority: KR
Inventors: 강희삼
Original assignee: 현대자동차주식회사
Priority date: 2009-03-11
Filing date: 2009-03-11
Publication date: 2010-09-24

Abstract

PURPOSE: An abrasion-resistant aluminum alloy for a vehicle is provided to improve abrasion-resistance and mechanical properties by uniformly dispersing soft and hard particles. CONSTITUTION: An abrasion-resistant aluminum alloy for a vehicle is composed of zinc 38~43 weight%, copper 2.5~3.5 weight%, silicon 8~9 weight%, manganese 0.2~0.5 weight%, and inevitable impurities. The main ingredient of the aluminum alloy is aluminum which is soft particles. The aluminum alloy reduces a friction coefficient. The silicon is hard particles and improves abrasion-resistance of the aluminum alloy.

Description

Wear-resistant aluminum alloy for vehicle {WEAR-RESISTANT ALUMINUM ALLOY FOR VEHICLES}

The present invention relates to aluminum alloys used in the production of wear resistant parts of vehicles.

In general, the shift fork for the transmission, the rear cover and the swash plate for the compressor are manufactured using materials having excellent wear resistance.

In order to manufacture such a wear-resistant component, an over-process Al-Si alloy or steel material is used. In general, the above-mentioned hyper-process Al-Si alloy is mainly prepared by Si content of 13.5-18 wt% and Cu content 2-4 wt%. The hyper-eutectic Al-Si alloy has 30-50 μm sized primary Si particles on the microstructure, and thus has excellent wear resistance compared to general Al-Si alloys.

However, the hypereutectic alloy has a problem in that castability is reduced due to high Si content, it is difficult to control Si particle size and its distribution, and impact resistance is reduced. In addition, the alloy is a specially developed alloy has a problem that the price is very high compared to the general aluminum alloy.

The present invention improves the mechanical properties such as impact resistance while maintaining the same level of wear resistance as the over-process Al-Si alloy to replace the over-process Al-Si alloy in order to solve such a conventional problem. The purpose is to provide a reduced wear-resistant aluminum alloy for vehicles.

The wear-resistant aluminum alloy for a vehicle according to the present invention for achieving the above object is composed of aluminum (Al) as a main component, zinc (Zn): 38 to 43% by weight, copper (Cu): 2.5 to 3.5% by weight, silicon (Si): 8-9% by weight, manganese (Mn): 0.2-0.5% by weight and other inevitable impurities.

Preferably, the silicon (Si) size in the wear resistant aluminum alloy structure is 20-30 μm.

In the present invention, the hard particles and the soft particles are uniformly dispersed due to the above technical configuration, thereby maintaining abrasion resistance equivalent to that of the over-process Al-Si alloy, improving mechanical properties such as impact resistance, and reducing costs.

Hereinafter, with reference to the accompanying table and the drawings looks at according to a preferred embodiment of the present invention.

The wear-resistant aluminum alloy for vehicles according to the present invention contains aluminum (Al) as a main component, zinc (Zn): 38 to 43% by weight, copper (Cu): 2.5 to 3.5% by weight, silicon (Si): 8 to 9 Weight%, manganese (Mn): 0.2 to 0.5% by weight is added by dissolving together in an electric furnace and prepared by solidification. The aluminum and zinc function to lower the friction coefficient as the soft particles, Al ₂ Cu particles of the silicon and intermetallic compound to increase the wear resistance of the alloy as hard particles. The soft particles and the hard particles are evenly distributed to improve wear resistance as a whole.

Referring to the wear-resistant aluminum alloy for vehicles according to the present invention in more detail, zinc (Zn) is added 38 to 43% by weight. When zinc is added in less than 38% by weight, the weight% of the soft particles of zinc is reduced, so that the effect of reducing the friction coefficient cannot be obtained. In addition, when zinc is added in excess of 43% by weight, mechanical properties of the entire alloy are deteriorated due to ductility of zinc itself, and thus the function as a structural material of the alloy is lost. Therefore, zinc should be added in the range of 38 to 43% by weight.

In the automotive wear-resistant aluminum alloy of the present invention, copper (Cu) is added to improve mechanical properties. Copper must be added in an amount of 2.5% by weight or more and 3.5% by weight or less to improve the mechanical properties of the alloy. If it is added less than 2.5% by weight can not be expected to improve the mechanical properties of the alloy, when added more than 3.5% by weight of the intermetallic compound is coarse, not evenly distributed on the aluminum alloy as well as stress Concentrated portions can be created and the elongation and tensile strength are reduced, rather the mechanical properties are degraded. Therefore, copper should be added at 2.5 to 3.5% by weight.

Silicon (Si), a key element added to improve wear resistance, should be added in an amount of 8 to 9 wt%. If less than 8% by weight of the silicon particles are not evenly distributed in the alloy is not expected to improve the overall wear resistance, if more than 9% by weight coarse silicon particles are formed, the workability of the alloy is reduced But also reduces wear resistance. The size of the silicon particles in the alloy is preferably formed in the 20 ~ 30㎛ level. When silicon is formed smaller than 20 µm, the silicon particles are not evenly distributed, so improvement of wear resistance of the alloy cannot be expected, and when larger than 30 µm, workability and wear resistance of the alloy deteriorate.

On the other hand, manganese (Mn), which is a trace element, is added in an amount of 0.2 to 0.5 wt% to enhance the matrix of aluminum. When the amount of manganese is added less than 0.2% by weight, it is not possible to expect the generation of minute precipitates, the effect of the present invention can not be achieved, and when the amount of manganese is added more than 0.5% by weight the particles become coarse As a result, mechanical properties of the aluminum alloy, such as lowering of the elongation, are lowered.

In the automotive wear-resistant aluminum alloy according to the present invention, since it contains an excess of zinc and silicon to obtain a high wear resistance effect, it does not require special heat treatment such as T6, T7 which proceeds to strengthen precipitation in other aluminum alloys. Do not. However, as can be seen in Figure 1 to ensure the stability of the material, only T5 heat treatment proceeds.

Hereinafter, the Example of this invention is demonstrated in detail with a comparative example.

In order to confirm the mechanical properties and wear resistance of the Al-Zn-Si-Mn alloy which is a wear-resistant aluminum alloy for a vehicle according to the present invention, Al, Zn: 40% by weight, Cu: 3% by weight, Si: 8% by weight , Mn: 0.2% by weight was added to prepare Al-40Zn-3Cu-8Si-0.2Mn alloy through a conventional casting process, as a comparative example is based on R14 alloy manufactured by Ryobi, Japan, that is Al To this, 14% by weight of Si and 3% by weight of Cu were used to use an aluminum alloy prepared by a conventional casting method.

The wear resistance and mechanical properties (tensile strength, elongation, impact resistance, and coefficient of friction) of the alloys according to the Examples and Comparative Examples were measured using conventional equipment, and the results are shown in Table 1 below.

division Comparative example Example Remarks Tensile Strength (MPa) 180-200 200-220 10% improvement Loss rate (%) 0.4-0.5 1 ~ 1.2 200% improvement Impact resistance (MJ / mm3) 0.2-0.6 0.6 ~ 1 150-200% improvement Coefficient of friction 0.06-0.08 0.05-0.08 Equivalence
(Reciprocating test / lubrication conditions)

As shown in Table 1 above, the automotive wear-resistant aluminum alloy according to an embodiment of the present invention is 10% tensile strength, in particular, elongation and impact resistance of 200%, while maintaining the same wear resistance and coefficient of friction as the conventional R14 alloy, It was confirmed that the mechanical properties were improved by improving 150% to 200%.

Figure 2 is a structure micrograph of a wear-resistant aluminum alloy for a vehicle according to the present invention, as described above, according to the wear-resistant Al-Zn-Cu-Si-Mn alloy according to the present invention replaces the existing hyper-processed Al-Si alloy It is a low-cost wear resistant alloy that can achieve improved mechanical properties while ensuring wear resistance that meets the required level through an even distribution of soft and hard particles in the microstructure.

While the present invention has been particularly shown and described with reference to specific embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the following claims It will be apparent to those of ordinary skill in the art.

1 is a manufacturing process of the wear-resistant aluminum alloy for a vehicle according to an embodiment of the present invention.

2 is a micrograph of a wear-resistant aluminum alloy tissue for a vehicle according to an embodiment of the present invention.

Claims

Aluminum (Al) as a main component, zinc (Zn): 38 to 43% by weight, copper (Cu): 2.5 to 3.5% by weight, silicon (Si): 8 to 9% by weight, manganese (Mn): 0.2 A wear-resistant aluminum alloy for a vehicle, which has a composition containing ˜0.5 wt% and other unavoidable impurities.

The wear-resistant aluminum alloy according to claim 1, wherein the silicon (Si) size in the structure is 20 to 30 µm.