JP2002356755A - METHOD FOR PRODUCING Cu-CONTAINING HYPER-EUTECTIC Al-Si ALLOY CAST MEMBER HAVING EXCELLENT WEAR RESISTANCE - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a Cu-containing hyper-eutectic Al-Si alloy cast member, in which primary crystal Si is uniformly and finely dispersed, and which has excellent wear resistance and machinability. SOLUTION: The molten metal of a hyper-eutectic Al-Si containing, by mass, 14.0 to 18.0% Si, 0.001 to 0.02% P and 2.0 to 5.0% Cu is prepared. The hyper- eutectic Al-Si alloy molten metal housed in a holding furnace on casting is held in the temperature range of (23×Si%+357) deg.C to (23×Si%+387) deg.C, and is poured from the holding furnace into a mold so as to be cooled at the average cooling rate of 2 to <1,000 deg.C/sec in the temperature range of (23×Si%+357) deg.C to a liquidus temperature, to form a cast structure in which the average particle size of primary crystal Si is controlled to 7 to 30 μm. As the hyper-eutectic Al-Si alloy, the one containing Mg, Fe, Ca, Mn, Cr, Ti and B in addition to the above Si, P and Cu can also be used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a highly wear-resistant C used for sliding members such as cylinder blocks for automobiles.
The present invention relates to a method for manufacturing a u-containing hypereutectic Al-Si based aluminum alloy cast member.

[0002]

2. Description of the Related Art A hypereutectic Al-Si based aluminum alloy has been conventionally used as an aluminum alloy cast member having excellent wear resistance and high damping ability. Hypereutectic Al-Si
In a cast aluminum alloy member, wear resistance and damping ability are improved by the primary crystal Si crystallized in the matrix. However, if the cooling rate at the time of casting solidification is low, the primary crystal Si is coarsened, the primary silicon is cracked and the wear resistance is deteriorated. Defects easily occur. On the other hand, if the dispersion of the primary crystal Si is non-uniform or too fine, there is no wear resistance effect.

[0003] Therefore, in order to secure the wear resistance and the machinability of the cast member, the primary crystal Si should have an appropriate size of 7 to 10 mm.
It is necessary to control to 30 μm, preferably 10 to 20 μm, and to uniformly disperse. Therefore, in order to disperse the primary crystal Si finely and uniformly, the cooling temperature in the temperature range between the liquidus temperature and the solidus temperature at which the primary crystal Si crystallizes during casting is increased, and conversely, In order to control the size of primary crystal Si to a certain size or more, the molten metal is temporarily maintained at a temperature between the liquidus temperature and the solidus temperature during casting to grow primary crystal Si (Japanese Patent Laid-Open No. 226636).

[0004] Further, in order to refine primary Si, P is added to a melt of a hypereutectic Al-Si alloy to generate heterogeneous nucleus AlP when primary Si is crystallized. Since a large amount of primary crystal Si is crystallized using this heterogeneous nucleus as a seed,
The primary crystal Si grains are refined, and coarsening of the primary crystal Si is suppressed. However, if the melting temperature or the holding temperature of the aluminum alloy is low, AlP grows and aggregates in the molten metal, and P does not sufficiently exert the function of refining primary crystal Si. Therefore, when casting a hypereutectic Al-Si alloy, the melting temperature and the holding temperature are 850-900 ° C. and 80 ° C., respectively.
For example, in a hypereutectic Al-Si alloy having a Si content of 18% by mass, the holding temperature is set to 850 ° C.

[0005] When the melting temperature and the holding temperature of the hypereutectic Al-Si alloy are set to be high, the cast member obtained has many casting defects due to the absorption gas and oxides, and not only deteriorates the mechanical properties but also decreases the mechanical properties. High melting and holding temperatures increase energy consumption and shorten the life of furnaces and dies, thus increasing manufacturing costs. Accordingly, the present invention requires that the melting temperature and the holding temperature be set to be excessively high by regulating the holding temperature of the hypereutectic Al-Si-based aluminum alloy in the hand furnace at the time of casting in relation to the Si content. To obtain a hypereutectic Al-Si alloy cast member exhibiting a sufficient primary crystal Si refining effect by P and exhibiting excellent wear resistance and high damping ability, Japanese Patent Laid-Open No.
As described in JP-A-222636, a hypereutectic Al-Si alloy melt is melted at (24.6 × Si% + 324) ° C. to (24.6 × S
i% + 354) It was proposed to maintain the temperature in the temperature range of 354 ° C. and to hold and cast the molten metal in the temperature range.

[0006]

By the way, hypereutectic Al
-Si-based aluminum alloys, when used in products that require mechanical strength, to increase the mechanical strength,
Several percent of Cu is added. However, when manufacturing a machine member by casting a hypereutectic Al-Si-based aluminum alloy containing Cu, the temperature of the molten metal in the hand furnace is set to (24.6 × S
Even if casting is performed at a temperature of not less than (i% + 324) ° C., a sufficient fine effect cannot be obtained, and primary crystal Si may be coarsened. The present invention has been devised in order to solve such a problem. The primary crystal Si is uniformly and finely dispersed, and the Cu-containing hypereutectic Al having excellent wear resistance and machinability is provided.
An object of the present invention is to provide a method of manufacturing a cast Si alloy member.

[0007]

SUMMARY OF THE INVENTION According to the present invention, a method for producing a Cu-containing hypereutectic Al-Si based aluminum alloy cast member having excellent abrasion resistance is provided in order to achieve the object.
Hypereutectic Al— containing 4.0 to 18.0% by mass, P: 0.001 to 0.02% by mass, and Cu: 2.0 to 5.0% by mass.
A hypereutectic Al-Si-based aluminum alloy melt prepared in a hand furnace at the time of casting is prepared by preparing a melt of Si alloy (23 × Si
% + 357) ° C. to (23 × Si% + 387) ° C., and a hypereutectic Al—Si alloy melt is poured into a mold from a hand-held furnace and cast, and the average grain size of primary crystal Si is 7 to 30μ
m, forming a cast structure adjusted to m.

As the hypereutectic Al-Si aluminum alloy, in addition to the above Si, P and Cu, Mg: 0.1 to 1.0
%, The Fe content is 1.5% by mass or less, the Ca content is 0.005% by mass or less, and Mn:
0.3 to 0.8% by mass, Cr: 0.05 to 0.3% by mass, Ti: 0.01 to 0.30% by mass, B: 0.000
Those containing any one or more of 5 to 0.01% by mass are preferable. Furthermore, in order to adjust the particle diameter of the primary crystal Si within a predetermined range, the temperature range of (23 × Si% + 357) ° C. to the liquidus temperature is set at an average cooling rate of 2 ° C./sec or more and less than 1000 ° C./sec. Casting is preferred.

[0009]

First, the composition of the hypereutectic Al-Si-based aluminum alloy targeted by the present invention will be described. Si: 14.0 to 18.0% by Mass Si is an important element in the Al-Si-based aluminum alloy for crystallizing primary Si and exhibiting wear resistance. However, when the Si content is less than 14.0% by weight, the amount of Si that can be crystallized as primary crystal Si is small, and it is possible to crystallize Si grains of a sufficient size and amount necessary to secure wear resistance. Can not. Conversely, when a large amount of Si exceeding 18.0% by weight is contained, the solidus of the alloy rises, so that the melting castability deteriorates, and the dispersion of primary Si tends to become non-uniform, so that crystallization occurs. Si has also increased in size,
Impact value and fatigue strength decrease.

P: 0.001 to 0.02% by mass P is added to this hypereutectic Al-Si-based aluminum alloy in order to generate a heterogeneous nucleus AlP effective as a seed for crystallizing primary Si. When the P content is less than 0.001% by weight, sufficient generation of heterogeneous nuclei cannot be expected and primary crystal Si
The effect of miniaturization becomes weaker. The effect of adding P is saturated at 0.02% by weight, and even if a large amount exceeding 0.02% by weight is added, not only the improvement corresponding to the added amount cannot be obtained, but also the castability such as the flow of molten metal deteriorates. I do. In addition, P may be added to the molten metal after the aluminum alloy is melted, or a master alloy containing P may be used as a raw material for melting in advance.

Cu: 2.0 to 5.0% by mass Cu has a function of strengthening the matrix of the aluminum alloy, thereby improving strength and wear resistance. In order to obtain such an effect, it is necessary to contain 2.0% by mass or more of Cu. However, when the Cu content exceeds 5.0% by mass, the occurrence of sink marks increases, and the corrosion resistance also deteriorates.

In the present invention, it is essential to adjust the content of the three components Si, P and Cu, but other components may be contained in the following ranges according to the required properties of the casting. . Mg: 0.1 to 1.0% by mass Mg is an element effective for improving the hardness, wear resistance, mechanical strength, and the like of an aluminum alloy. Can be obtained. However, when Mg exceeds 1.0% by mass, the toughness tends to decrease.

Fe: 1.5 mass% or less Fe is an Al—Si—Fe-based intermetallic compound and Al—
The Si-Fe-Mn-Cr-based intermetallic compound is finely crystallized to improve wear resistance. However, when a large amount of Fe is mixed in the aluminum alloy, particularly, the Al-Fe A coarse compound of the system is formed, which causes microporosity. As a result, the toughness and strength of the obtained aluminum alloy will be reduced. Therefore, in the present invention, the Fe content is preferably set to 1.5% by mass or less.

Ca: 0.005% by mass or less If the Ca content exceeds 0.005% by mass, the internal shrinkage becomes large at the time of casting, resulting in a decrease in castability. Also, P
Inhibits the primary crystal Si from being refined. Therefore C
The content of a is preferably set to 0.005% by mass or less. Mn: 0.3 to 0.8% by mass Mn disperses Al-Si-Fe-Mn-Cr intermetallic compounds finely and uniformly, improves wear resistance, and strengthens the matrix of the aluminum alloy. , An alloy component that improves mechanical properties. If the Mn content is less than 0.3% by mass, the wear resistance is not sufficient, and if it exceeds 0.8% by mass, the mechanical properties deteriorate. Therefore, the content of Mn is preferably set to 0.3 to 0.8% by mass.

Cr: 0.05-0.3% by mass Cr contains primary crystal Si in a matrix of an aluminum alloy.
Is an important element in uniformly dispersing
It also works effectively to improve mechanical properties. Al-Si
-It is an important alloying element in dispersing the Fe-Mn-Cr intermetallic compound as fine crystallized matter uniformly and improving wear resistance. And such an action
Appears at a content of 0.05% by mass or more. However, when the Cr content exceeds 0.30% by mass, castability and mechanical properties decrease. Therefore, when Cr is contained, the content is preferably in the range of 0.05 to 0.30% by mass.

[0016] Ti: 0.01 to 0.30% by mass, B:
0.0005 to 0.01% by mass Ti and B are effective elements for acting as a refining material at the time of casting, improving castability and making the structure uniform. To obtain these effects, 0.05
It is necessary to contain Ti by mass or more and B by 0.0005 mass% or more. However, if Ti exceeds 0.30% by mass and B exceeds 0.01% by mass, the mechanical properties decrease. Therefore, when Ti and B are contained, the content is preferably in the above range. Components other than those described above are regarded as impurities, and the content thereof is preferably minimized.

Next, the feature of the present invention, that is,
The cooling conditions will be described. Melt holding temperature in hand furnace: (23 × Si% + 357) ° C.
~ (23 × Si% + 387) ° C. The present inventors have previously made hypereutectic Al-S having a low Cu content.
A temperature (24.6 × Si% + 324) ° C. at which AlP of the molten i-based aluminum alloy starts to be aggregated was discovered. In Japanese Patent Application Laid-Open No. 11-222636, the molten metal was placed in a hand-held furnace to prevent aggregation of AlP (24). .6 × Si% + 324)
It was proposed to cast at a temperature of ℃. However, the present inventors have further studied and found that the temperature at which this AlP starts agglomeration changes depending on the Cu content, and the temperature increases as the amount increases. It is presumed that this is because P and Cu form a compound, and the compound of P and Cu facilitates aggregation of AlP. The reason why Cu does not participate in the approximation is that C
It is presumed that since the amount of u is very large, even if Cu is added at 2% by mass or more, the amount of the compound of Cu and P does not increase.

Then, hypereutectic Al containing 14.0 to 18.0% by mass of Si and 2.0 to 5.0% by mass of Cu.
In the case of a -Si alloy, it was found that AlP aggregation started at a temperature lower than (23 x Si% + 357) C. Therefore, in the present invention, a molten metal of a hypereutectic Al-Si-based aluminum alloy containing Cu is placed in a hand-held furnace at (23 × Si% + 35).
7) By keeping the temperature at not less than ° C, aggregation of AlP was prevented, and coarsening of primary crystal Si was suppressed. If the molten metal holding temperature does not reach this range, the added P agglomerates as AlP, and the AlP serving as the nucleus of the primary crystal Si decreases or becomes coarse, so that the primary crystal Si tends to become coarse. However, at a molten metal holding temperature exceeding this temperature range, AlP
Does not reduce the amount of P effective for the formation of primary crystal Si nuclei due to the aggregation of P.

This (23 × Si% + 357) ° C. is a temperature found by the present inventors as described in Examples described later, and depends on the Si content. The inflection points appearing in the temperature dependence curves of the average grain size and the number of grains of crystalline Si are shown. Hypereutectic Al at a temperature above this inflection point
-When holding a Si-based aluminum alloy, coarsening of primary Si is suppressed, and primary Si is dispersed with an appropriate particle size and an appropriate distribution density, so that a cast member excellent in wear resistance and machinability can be obtained. . However, an excessively high holding temperature causes problems such as deterioration of the mold and large consumption of energy. Therefore, in the present invention, the upper limit of the holding temperature of the alloy melt to be cast is 30 ° C. higher than the inflection point temperature (23 × Si% +
387) Set to ° C. In the hand furnace, only the temperature of the molten metal is adjusted, and the molten metal is cast immediately after an appropriate time has elapsed.

(23 × Si% + 357) ° C. to liquidus temperature
Cooling rate: 2 to 1000 ° C./sec. Even if the molten metal of the hypereutectic Al—Si-based aluminum alloy containing Cu is kept at (23 × Si% + 357) ° C. or more in a hand-held furnace. Primary crystal Si may be coarsened in some cases. When the cause was investigated, it was found that (23 × Si% + 3)
57) Even if the temperature is maintained at not less than ° C, the temperature of the molten metal becomes (23 × Si % + 357) The temperature is lowered to less than ° C, and the temperature is maintained for a short time but at that temperature, AlP is aggregated, the number of nuclei is reduced, and the primary crystal Si crystallized thereafter is increased. I understood.

Further studies have shown that it has been conventionally thought that the grain size of primary Si is affected by the cooling rate between the liquidus temperature and the solidus temperature at which primary Si is crystallized. Actually, primary Si has not yet crystallized (23 × Si% + 3).
57) Depending on the cooling temperature between C and the liquidus temperature, primary S
It was found that the i particle size was affected. FIG. 1 shows Al-1
The number of primary crystal Si per 1 mm ² in an aluminum alloy of 5.1 mass% Si and 2.9 mass% Cu and (23 ×
It shows the relationship between the cooling rate between Si% + 357) ° C. and the liquidus temperature (indicated by ○ in the figure) and the relationship between the cooling rate between the liquidus temperature and the solidus temperature (indicated by ▲ in the figure). . As can be seen from the figure, there is a variation in the relationship between the number of primary Si and the cooling rate between the liquidus temperature and the solidus temperature (indicated by が in the figure). 23 × Si% + 357)
The cooling rate between ° C and the liquidus temperature shows a very high correlation.

Therefore, in the present invention, in order to make the primary crystal Si finer, the primary crystal Si above the liquidus exceeds the cooling rate between the liquidus temperature and the solidus temperature, which has been conventionally considered. Focusing on the importance of the cooling rate in the temperature range where crystallization has not yet occurred, the liquidus temperature and the temperature at which AlP starts aggregation (2
The cooling rate of the molten aluminum alloy was controlled in a temperature range of 3 × Si% + 357) ° C. That is, C
When casting a u-containing hypereutectic Al-Si-based aluminum alloy melt, cooling at a rate of 2 ° C / sec or more to less than 1000 ° C / sec between (23 × Si% + 357) ° C and liquidus temperature. And When casting is performed within this cooling rate range, primary crystal Si can be surely uniformly dispersed in a size of 7 to 30 μm. If the temperature is lower than 2 ° C./sec, the aggregation of AlP proceeds, and the number of AlPs serving as nuclei for the crystallization of primary Si decreases, and as a result, the particle size of primary Si exceeds 30 μm. Conversely, cooling at a rate of 1000 ° C./sec or more
P agglomeration does not progress and the number of P increases, and the crystallized primary crystal Si becomes less than 7 μm which does not contribute to improvement in wear resistance.

[0023]

EXAMPLES Example 1 As shown in Table 1, various aluminum alloys having different Si contents were prepared, and after melting, each molten alloy was cooled to various holding temperatures and held at each holding temperature for 1 minute. After that, it was die-cast into a round bar having a diameter of 18 mm. When casting, the temperature range between the holding temperature and the liquidus temperature is set to an average cooling rate of 1
Casting was performed at 35 ° C./sec. The cast structure of the obtained cast member was examined, and the average grain size and the number of primary crystal Si particles were measured using a Carl Zeiss KS400 image analyzer. Examples of the results are shown in FIGS.

[0024]

From these four figures, it can be understood that the number of primary crystals rapidly decreases and the average grain size increases when the temperature is maintained at a temperature lower than the specific temperature. In a temperature range lower than this rapidly changing temperature, the rate at which the average grain size of primary crystal Si increases and the rate at which the number of grains increases as the holding temperature decreases increases. In the high temperature range, there is almost no change in the rate at which the average grain size of primary crystal Si decreases and the rate at which the number of grains increases in accordance with the increase in the holding temperature. Therefore, it was determined that AlP had not yet aggregated in a temperature range higher than the above-mentioned rapidly changing temperature, and that AlP had started to aggregate from this temperature.

It is apparent from the difference between FIGS. 2 to 5 that the inflection point changes depending on the Si content. Figure 2
When the inflection point temperature obtained from FIG. 5 is arranged in relation to the Si content, a strong correlation is seen as shown in FIG. Therefore, when the inflection point temperature is approximately calculated as T (° C.), T =
A relationship of (23 × Si% + 357) ° C. is derived.

Example 2 Various aluminum alloys having the compositions shown in Table 2 were melted, and each molten metal was kept at (23 × Si% + 387) ° C. for 1 hour, and then cast into a flat plate by gravity casting. The temperature of the molten metal in the pool is set to (23 × Si% + 377) ° C., and the temperature is set to (23 × Si% + 357) ° C. in the mold.
1.6 ° C / sec, 3.4 ° C / sec, 10 ° C / sec
Casting was performed so as to be cooled at a rate of 22 ° C./sec, 122 ° C./sec, and 1000 ° C./sec. And the obtained casting is 4
After holding at 90 ° C. for 6 hours and performing a solution treatment, quenching with water, and then holding at 180 ° C. for 6 hours and performing an aging treatment, the average particle diameter of primary Si was measured by image analysis. . FIG. 7 shows the sectional structure of the casting obtained at each cooling rate. Further, a friction and wear test using cast iron as a mating material was also performed.
In the friction / wear test, a pin-on-disk type friction / wear tester was used.
km and a surface pressure of 18 MPa. The weight of the abrasion test specimen was measured before and after the test, and the abrasion resistance was evaluated based on the weight reduction ratio of the test specimen in the abrasion test. Table 3 shows the results.

[0028]

[0029]

As can be seen from the results shown in Table 3, the casting specified in the present invention and cooled between (23 × Si% + 357) ° C. and the liquidus temperature at 2 ° C./sec or more and less than 1000 ° C./sec, The primary crystal Si has an average particle size in the range of 7 to 30 μm, and has excellent wear resistance. On the other hand, in the casting of the comparative example cooled at less than 2 ° C./sec, the primary crystal Si was about 50 μm, and the wear resistance was deteriorated probably because large primary crystal Si was chipped and dropped off during the friction and wear test. Was. Also, 1000
It was found that in the casting of the comparative example cooled at a high rate of ° C./sec, the average grain size of the primary crystal Si did not reach 7 μm, and could not contribute to the improvement of the wear resistance.

[0031]

As described above, in the present invention, it is determined by the relationship with the Si content (23 × Si% + 35).
7) After holding the Cu-containing hypereutectic Al-Si alloy immediately before casting in a temperature range of ° C to (23 x Si% + 387) ° C, it is cast into a mold. By this holding treatment, it is possible to control the number of heteronuclear AlPs serving as seeds of crystallized primary crystal Si, to optimize the average grain size and distribution density of the primary crystal Si crystallized in the cast structure, Thus, a cast member having excellent machinability can be obtained. At the time of casting, (23 × Si% + 357)
By setting the cooling rate between ℃ and the liquidus temperature within a predetermined range, regardless of alloy components other than Si, P and Cu,
The average grain size of the primary crystal Si can be controlled to 7 to 30 μm, the distribution density is made constant, and the wear resistance of the cast member can be further improved.

[Brief description of the drawings]

FIG. 1 Al-15.1% by mass Si-2.9% by mass C
primary crystal S per 1 mm ² in aluminum alloy u
The relationship between the number of i and the cooling rate between (23 × Si% + 357) ° C. and the liquidus temperature (marked with ○ in the figure) and the relationship between the cooling rate between the liquidus temperature and the solidus temperature (marked with ▲ in the figure) )

FIG. 1 is a graph showing the effect of the holding temperature on the average grain size and the number of primary crystal Si particles of a Cu-containing hypereutectic Al-Si alloy melt having a Si content of 13.7% by weight.

FIG. 3 shows alloy No. 2 is a graph showing the effect of the holding temperature on the average grain size and the number of primary Si crystals in a Cu-containing hypereutectic Al-Si alloy melt having a Si content of 15.4% by weight.

FIG. 3 is a graph showing the influence of the holding temperature on the average grain size and the number of primary Si crystals in a Cu-containing hypereutectic Al-Si alloy melt having a Si content of 16.4% by weight.

FIG. 5 shows alloy No. 4 is a graph showing the influence of the holding temperature on the average grain size and the number of primary Si crystals in a Cu-containing hypereutectic Al-Si alloy melt having a Si content of 17.0% by weight.

FIG. 6 is a graph showing the relationship between the inflection point temperature T and the Si content in the hypereutectic Al—Si alloy melts of alloy numbers 1 to 4.

FIG. 7 shows a hypereutectic Al-Si alloy melt containing 15.0% by mass of Si, 0.01% by mass of P, and 3.0% by mass of Cu, (a) 1.6 ° C./sec. b) 3.4 ° C./sec.
(C) 122 ° C./sec, (d) Surface microscopic observation model of a material cooled and cast at 1000 ° C./sec.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C22F 1/00 611 C22F 1/00 611 (72) Inventor Akio Hashimoto 1-34 Kabara, Kambara-cho, Anbara-gun, Shizuoka Prefecture No. 1 Nippon Light Metal Co., Ltd. Group Technology Center (72) Inventor Satoshi Suzuki 1-34-1 Kambara, Kambara-cho, Anbara-gun, Shizuoka Prefecture Nippon Light Metal Co., Ltd. Group Technology Center

Claims (3)

[Claims] 1. Si: 14.0 to 18.0% by mass, P:
A hypereutectic Al-Si alloy melt containing 0.001 to 0.02 mass% and Cu: 2.0 to 5.0 mass% is prepared and stored in a hand furnace at the time of casting. The molten aluminum alloy is heated from (23 × Si% + 357) ° C. to (23 × Si
% + 387) ° C., and injecting a hypereutectic Al—Si alloy melt from a hand furnace into a mold to form a cast structure in which the average grain size of primary crystal Si is adjusted to 7 to 30 μm. Cu-containing hypereutectic Al-S with excellent wear resistance
A method for manufacturing an i-type aluminum alloy cast member. 2. An excellent wear resistance according to claim 1, wherein the casting is performed in a temperature range of (23 × Si% + 357) ° C. to a liquidus temperature at an average cooling rate of 2 ° C./sec or more and less than 1000 ° C./sec. Cu
A method for producing a cast alloy member containing excessive Al-Si-based aluminum alloy. 3. The hypereutectic Al—Si alloy melt, wherein Si: 1
4.0 to 18.0 mass%, P: 0.001 to 0.02 mass%, Cu: 2.0 to 5.0 mass%, Mg: 0.1 to
1.0% by mass, and further, the Fe content is 1.5% by mass.
Hereinafter, the Ca content is set to 0.005% by mass or less, Mn: 0.3 to 0.8% by mass, Cr: 0.05 to
0.3% by mass, Ti: 0.01 to 0.30% by mass, B:
3. A Cu-containing hypereutectic Al-Si-based aluminum alloy casting having excellent wear resistance according to claim 1 or 2, wherein at least one of 0.0005 to 0.01% by mass is contained and the balance is substantially Al. Manufacturing method of the member.