CN112813318A - Aluminum alloy material for casting - Google Patents

Abstract

The invention discloses an aluminum alloy material for casting, which comprises the following components in percentage by mass: 7.2 to 7.8 percent of Si, less than or equal to 0.45 percent of Fe, 3.1 to 3.6 percent of Cu, 0.2 to 0.5 percent of Mn, 0.25 to 0.4 percent of Mg, 0.2 to 0.3 percent of Zn, less than or equal to 0.04 percent of Cr, 0.1 to 0.25 percent of Ni, 0.12 to 0.2 percent of Ti, 0.004 to 0.01 percent of Sr, less than or equal to 0.1 percent of Pb, and the balance of Al and inevitable impurities. The invention can reasonably solve the problems of poor comprehensive mechanical property and high formula cost of cast aluminum alloy in the prior art.

Description

Aluminum alloy material for casting

Technical Field

The invention relates to the technical field of aluminum alloy materials, in particular to an aluminum alloy material for casting.

Background

Casting, namely smelting metal, manufacturing a casting mold, injecting the molten metal into the casting mold, and cooling and solidifying to obtain a metal part blank with certain shape, size and performance. Most of raw materials adopted by casting parts produced by traditional casting are only single metal or formed by melting and mixing a plurality of metals, but the casting parts have the advantages of heavy weight, general strength and lower mechanical property, are particularly long-term in extreme environments with high temperature, high pressure and corrosiveness, have short service life and are easy to deform and even break. The metals such as chromium, titanium, tin, cadmium and the like can improve the mechanical strength of the aluminum alloy, so that a casting part can resist high temperature and corrosion, wherein the compound formed by tin and aluminum can ensure that the molecular arrangement in the alloy is more regular, and the mechanical property is greatly improved.

Therefore, in order to solve the problem, the aluminum alloy material for casting needs to be provided, and the problems of poor comprehensive mechanical property and high formula cost of the cast aluminum alloy in the prior art are reasonably solved.

Disclosure of Invention

The invention aims to provide an aluminum alloy material for casting, which reasonably solves the problems of poor comprehensive mechanical property and high formula cost of cast aluminum alloy in the prior art.

In order to solve the technical problems, the invention adopts the following technical scheme:

the aluminum alloy material for casting comprises the following components in percentage by mass: 7.2 to 7.8 percent of Si, less than or equal to 0.45 percent of Fe, 3.1 to 3.6 percent of Cu, 0.2 to 0.5 percent of Mn, 0.25 to 0.4 percent of Mg, 0.2 to 0.3 percent of Zn, less than or equal to 0.04 percent of Cr, 0.1 to 0.25 percent of Ni, 0.12 to 0.2 percent of Ti, 0.004 to 0.01 percent of Sr, less than or equal to 0.1 percent of Pb, and the balance of Al and inevitable impurities.

Preferably, the purity of the silicon, iron, copper, manganese, magnesium, chromium, zinc, titanium and aluminum is higher than 99.8%.

Preferably, the Al, Zn and Mg are respectively selected from commercially pure aluminum, commercially pure zinc and commercially pure magnesium; the Cu and the rare earth element RE are added in an aluminum-copper intermediate alloy and an aluminum-rare earth intermediate alloy; the Ti and the B are added in an Al-Ti-B intermediate alloy; the Sr and the Zr are added by intermediate alloy of aluminum strontium and aluminum zirconium.

Preferably, the steps comprise the following processes:

(1) drying materials: respectively preheating raw materials of industrial pure aluminum, industrial pure zinc, industrial pure magnesium, aluminum-copper intermediate alloy, aluminum-rare earth intermediate alloy, aluminum-titanium-boron intermediate alloy, aluminum strontium and aluminum-zirconium intermediate alloy to 200-300 ℃, and preserving heat for 0.5-2 hours;

(2) smelting: when the temperature is 200-300 ℃, adding industrial pure aluminum and aluminum-copper intermediate alloy, and stirring until the mixture is melted down; when the temperature of the melt is reduced to 680-700 ℃, adding industrial pure zinc and industrial pure magnesium for melting, and stirring until the melt is clear; heating the melt to 735-;

(3) refining: heating the melt to 735-; skimming dross and standing the melt;

(4) degassing: adding a covering agent into the melt prepared in the step (3), and stirring for 5-10 minutes in a protective atmosphere;

(5) thinning: and (4) adding an aluminum-titanium-boron intermediate alloy and/or one or two of an aluminum-strontium intermediate alloy and an aluminum-zirconium intermediate alloy into the melt prepared in the step (4), refining, and skimming dross to obtain an aluminum alloy melt.

Compared with the prior art, the invention has the beneficial technical effects that:

the aluminum alloy material for casting has high strength, good heat resistance, high strength, toughness and good cutting performance, and the strength reaches over 223 Mpa; the melt fluidity and the high-temperature resistance strength of the alloy are improved, and the alloy also has low porosity and low hot cracking tendency, so that the comprehensive mechanical property of the alloy is improved; the alloy has good casting performance, the casting performance is superior to that of ENAC-46300 through multiple casting tests on castings of automobile structural parts, automobile engine cylinder heads and the like, the strength stability of the material can be ensured, the ductility is good, the economy is remarkable, and the alloy is particularly suitable for being used as a cast aluminum alloy material.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The aluminum alloy material for casting comprises the following components in percentage by mass: 7.2 to 7.8 percent of Si, less than or equal to 0.45 percent of Fe, 3.1 to 3.6 percent of Cu, 0.2 to 0.5 percent of Mn, 0.25 to 0.4 percent of Mg, 0.2 to 0.3 percent of Zn, less than or equal to 0.04 percent of Cr, 0.1 to 0.25 percent of Ni, 0.12 to 0.2 percent of Ti, 0.004 to 0.01 percent of Sr, less than or equal to 0.1 percent of Pb, and the balance of Al and inevitable impurities.

Examples

Example 1

The aluminum alloy material for casting of the embodiment comprises the following components in percentage by weight: 7.25% of Si, 0.35% of Fe, 3.2% of Cu, 0.4% of Mn, 0.35% of Mg, 0.25% of Zn, 0.02% of Cr, 0.15% of Ni, 0.16% of Ti, 0.04% of Pb, 0.008% of Sr, and the balance of Al and inevitable impurities. The tensile strength of the aluminum alloy material for casting reaches 223Mpa, the yield limit reaches 180Mpa, the elongation is 3.14, and the hardness is 91 HBw.

Example 2

The aluminum alloy material for casting of the embodiment comprises the following components in percentage by weight: 7.25% of Si, 0.38% of Fe, 3.55% of Cu, 0.38% of Mn, 0.35% of Mg, 0.25% of Zn, 0.02% of Cr, 0.15% of Ni0, 0.16% of Ti, 0.05% of Pb, 0.008% of Sr, and the balance of Al and inevitable impurities. The tensile strength of the aluminum alloy material for casting reaches 241Mpa, the yield limit reaches 182Mpa, the elongation is 3.02, and the hardness is 92 HBw.

Example 3

The aluminum alloy material for casting of the embodiment comprises the following components in percentage by weight: 7.5% of Si, 0.42% of Fe, 3.3% of Cu, 0.36% of Mn, 0.38% of Mg, 0.25% of Zn, 0.02% of Cr, 0.15% of Ni, 0.16% of Ti, 0.06% of Pb, 0.008% of Sr, and the balance of Al and inevitable impurities. The tensile strength of the aluminum alloy material for casting reaches 232Mpa, the yield limit reaches 175Mpa, the elongation is 3.15, and the hardness is 92 HBw.

Example 4

The aluminum alloy material for casting of the embodiment comprises the following components in percentage by weight: 7.51% of Si, 0.42% of Fe, 3.5% of Cu, 0.35% of Mn, 0.35% of Mg, 0.25% of Zn, 0.02% of Cr, 0.15% of Ni, 0.16% of Ti, 0.06% of Pb, 0.006% of Sr, and the balance of Al and inevitable impurities. The tensile strength of the aluminum alloy material for casting reaches 245Mpa, the yield limit reaches 188Mpa, the elongation is 3.01, and the hardness is 93 HBw.

Example 5

The aluminum alloy material for casting of the embodiment comprises the following components in percentage by weight: 7.73% of Si, 0.44% of Fe, 3.55% of Cu, 0.35% of Mn, 0.35% of Mg, 0.25% of Zn, 0.02% of Cr, 0.15% of Ni0.16% of Ti, 0.05% of Pb, 0.006% of Sr, and the balance of Al and inevitable impurities. The tensile strength of the aluminum alloy material for casting reaches 262Mpa, the yield limit reaches 198.4Mpa, the elongation is 2.86, and the hardness is 105 HBw.

Example 6

The aluminum alloy material for casting of the embodiment comprises the following components in percentage by weight: 7.75% of Si, 0.25% of Fe, 3.55% of Cu, 0.35% of Mn, 0.35% of Mg, 0.25% of Zn, 0.02% of Cr, 0.15% of Ni0.16% of Ti, 0.05% of Pb, 0.006% of Sr, and the balance of Al and inevitable impurities. The tensile strength of the aluminum alloy material for casting reaches 255Mpa, the yield limit reaches 185Mpa, the elongation is 2.98, and the hardness is 101 HBw.

When the invention works, the steps comprise the following processes:

(1) drying materials: respectively preheating raw materials of industrial pure aluminum, industrial pure zinc, industrial pure magnesium, aluminum-copper intermediate alloy, aluminum-rare earth intermediate alloy, aluminum-titanium-boron intermediate alloy, aluminum strontium and aluminum-zirconium intermediate alloy to 200-300 ℃, and preserving heat for 0.5-2 hours;

(2) smelting: when the temperature is 200-300 ℃, adding industrial pure aluminum and aluminum-copper intermediate alloy, and stirring until the mixture is melted down; when the temperature of the melt is reduced to 680-700 ℃, adding industrial pure zinc and industrial pure magnesium for melting, and stirring until the melt is clear; heating the melt to 735-;

(3) refining: heating the melt to 735-; skimming dross and standing the melt;

(4) degassing: adding a covering agent into the melt prepared in the step (3), and stirring for 5-10 minutes in a protective atmosphere;

(5) thinning: and (4) adding an aluminum-titanium-boron intermediate alloy and/or one or two of an aluminum-strontium intermediate alloy and an aluminum-zirconium intermediate alloy into the melt prepared in the step (4), refining, and skimming dross to obtain an aluminum alloy melt.

The research of the embodiment 1-6 shows that the strength and the hardness of the aluminum alloy prepared by the invention are all improved; the tensile strength reaches 223-262MPa, the yield limit reaches 175-198.4MPa, the elongation is 2.86-3.15, the hardness is 91-105HBw, and the mechanical property of the aluminum alloy material is obviously superior to that of the ENAC-46300 alloy. (ENAC-46300 tensile strength up to 180Mpa, yield strength up to 100Mpa, elongation 1, hardness 80HBw)

The above-described embodiments are only preferred embodiments of the present invention, and are not intended to limit the scope of the present invention, and various modifications and variations of the technical solution of the present invention may be made by those skilled in the art without departing from the spirit of the present invention, which is defined by the claims of the present invention.

Claims (4)

1. The aluminum alloy material for casting is characterized by comprising the following components in percentage by mass: 7.2 to 7.8 percent of Si, less than or equal to 0.45 percent of Fe, 3.1 to 3.6 percent of Cu, 0.2 to 0.5 percent of Mn, 0.25 to 0.4 percent of Mg, 0.2 to 0.3 percent of Zn, less than or equal to 0.04 percent of Cr, 0.1 to 0.25 percent of Ni, 0.12 to 0.2 percent of Ti, 0.004 to 0.01 percent of Sr, less than or equal to 0.1 percent of Pb, and the balance of Al and inevitable impurities.

2. An aluminium alloy casting material according to claim 1, wherein the purity of the silicon, iron, copper, manganese, magnesium, chromium, zinc, titanium and aluminium is greater than 99.8%.

3. The aluminum alloy casting material according to claim 1, wherein the Al, Zn and Mg are each selected from the group consisting of industrially pure aluminum, industrially pure zinc and industrially pure magnesium; the Cu and the rare earth element RE are added in an aluminum-copper intermediate alloy and an aluminum-rare earth intermediate alloy; the Ti and the B are added in an Al-Ti-B intermediate alloy; the Sr and the Zr are added by intermediate alloy of aluminum strontium and aluminum zirconium.

4. An aluminum alloy material for casting according to claim 1, wherein said step comprises the steps of:

(1) drying materials: respectively preheating raw materials of industrial pure aluminum, industrial pure zinc, industrial pure magnesium, aluminum-copper intermediate alloy, aluminum-rare earth intermediate alloy, aluminum-titanium-boron intermediate alloy, aluminum strontium and aluminum-zirconium intermediate alloy to 200-300 ℃, and preserving heat for 0.5-2 hours;

(2) smelting: when the temperature is 200-300 ℃, adding industrial pure aluminum and aluminum-copper intermediate alloy, and stirring until the mixture is melted down; when the temperature of the melt is reduced to 680-700 ℃, adding industrial pure zinc and industrial pure magnesium for melting, and stirring until the melt is clear; heating the melt to 735-;

(3) refining: heating the melt to 735-; skimming dross and standing the melt;

(4) degassing: adding a covering agent into the melt prepared in the step (3), and stirring for 5-10 minutes in a protective atmosphere;

(5) thinning: and (4) adding an aluminum-titanium-boron intermediate alloy and/or one or two of an aluminum-strontium intermediate alloy and an aluminum-zirconium intermediate alloy into the melt prepared in the step (4), refining, and skimming dross to obtain an aluminum alloy melt.