CN103469033A - Vehicle body aluminum alloy section bar and making method thereof - Google Patents

Abstract

The invention discloses a vehicle body aluminum alloy section bar and a making method thereof. The vehicle body aluminum alloy section bar comprises, by mass, 0.06-0.12% of Si, 0.15-0.25% of Fe, 0.3-0.5% of Mn, 1.4-1.8% of Mg, 4.0-4.5% of Zn, 0.2-0.3% of Cr, 0.03-0.04% of Ni, 0.12-0.16% of Zr, 0.04-0.08% of Hf, 0.03-0.05% of Re, 0.04-0.08% of La, 0.02-0.023% of Sm, 0.015-0.025% of Pr, 0.10% or less of Cu, and the balance Al. The aluminum alloy section bar has the advantages of excellent comprehensive properties, high strength, good plasticity, good stress and corrosion resistances, good welding and processing performances and low welding crack tendency, and can be widely used as a vehicle body welding material.

Description

Aluminium alloy extrusions and manufacture method thereof for a kind of car body

Technical field

The present invention relates to aluminium alloy extrusions and manufacture method thereof for a kind of car body, belong to the aluminum alloy materials technical field.

Background technology

Aluminium alloy because its density is little, specific tenacity and specific rigidity is high, good springiness, good, corrosion-resistant, wear-resisting, the easy surface colour of shock resistance, good processing forming and high reclaiming etc., transportation is extraordinarily paid close attention to the commercial aluminum alloy section bar.Existing large of the automobile-used aluminium alloy extrusions of communications and transportation needs dependence on import, and the anti-stress corrosiveness of domestic aluminium alloy extrusions, welding property and physical strength also are difficult to reach the standard of external aluminium alloy.

Summary of the invention

In order to address the above problem ,the invention provides aluminium alloy extrusions and manufacture method thereof for a kind of car body, improve anti-stress corrosiveness, physical strength and the welding property of alloy profile.

The technical solution used in the present invention is as follows:

A kind of car body aluminium alloy extrusions is characterized in that: its each element consists of by mass percentage: Si 0.06-0.12, Fe 0.15-0.25, Mn 0.3-0.5, Mg 1.4-1.8, Zn 4.0-4.5, Cr 0.2-0.3, Ni 0.03-0.04, Zr 0.12-0.16, Hf 0.04-0.08, Re 0.03-0.05, La 0.04-0.08, Sm 0.02-0.03, Pr 0.015-0.025, Cu≤0.10, surplus are aluminium.

The manufacture method of aluminium alloy extrusions for car body is characterized in that: by above-mentioned alloying constituent, the furnace charge prepared is dropped into to smelting furnace, be heated to 750-780 ℃, treat that metal all melts, stir 35-45 minute, detect alloying constituent and adjust; Then add refining agent to carry out refining, refining temperature is 720-740 ℃, and refining time is 15-25 minute, standing 20-30 minute after refining, start casting after skimming, casting temp is 730-750 ℃, casting speed is 70-80mm/min, and cooling water flow is 1600-1800 L/min; Be warming up to 460-480 ℃ after casting, the insulation 12-16 hour, the high wind air cooling to 180-220 ℃ again water-cooled to room temperature; Then ingot casting is heated to 490-510 ℃, uses the extrusion machine extrusion molding, extruding rate is 1-3mm/s; Air-cooled section bar surface temperature, after 120-150 ℃, is put into 0-3 ℃ of icy salt solution and is down to rapidly below 50 ℃; The aluminium alloy extrusions that then will take out from salt solution first is warming up to 110-120 ℃ with 30-40 ℃/h, insulation 6-8h; Then be warming up to 160-180 ℃ with 20-30 ℃/h, insulation 5-10h; Be cooled to 60-70 ℃ with 40-60 ℃/h again, insulation 8-12h; Be warming up to 150-170 ℃ with 30-40 ℃/h again, insulation 4-6h, finally be cooled to 80-90 ℃ with 50-60 ℃/h, insulation 10-15h, and air cooling to the room temperature of coming out of the stove obtains aluminium alloy extrusions of the present invention.

Described refining agent preparation method is as follows: a. takes the raw material of following weight part: Repone K 5-10, sodium-chlor 8-12, aluminum fluoride 5-10, magnesium nitride 8-12, titanium boride 4-8, sodium aluminum fluoride 10-15, wollastonite 4-8, wilkinite 3-5; B. above-mentioned sodium aluminum fluoride, wollastonite, wilkinite were pulverized to the 300-400 mesh sieve, after mixing, add the aluminium nitride of 2-3%, the Di(dioctylpyrophosphato) ethylene titanate of 0.5-1%, the nano-sized carbon of 1-2%, the Zinic stearas of 1-1.5%, 2000-3000rpm high-speed stirring 10-15min, take out and dry, under 1200-1600 ℃, calcine 2-3h, then shrend is cooling, grind, stand-by; C. by all the other each heating raw materials to 750-800 ℃, after its whole meltings, the clarification 1-2h, top clear liquor is poured into water to cold quenching, obtain broken particle, porphyrize is crossed the 200-400 mesh sieve, stand-by; D. mixing of materials step b, c obtained stirs and obtains described refining agent.

The de-percentage of admixture of refining agent of the present invention between 65-75%, remove the inclusion in aluminium alloy and make inclusion modification effective, purify aluminium alloy and improved internal soundness, degree of porosity reduces the 1-2 degree, is controlled effectively.

Beneficial effect of the present invention:

Aluminium alloy extrusions excellent combination property of the present invention, intensity is high, and plasticity is good, and anti-stress corrosiveness is good, has good welding and processing characteristics, and welding crack proneness is low, is widely used in the car body welding material.

Embodiment

A kind of car body aluminium alloy extrusions, its each element consists of by mass percentage: Si 0.06-0.12, Fe 0.15-0.25, Mn 0.3-0.5, Mg 1.4-1.8, Zn 4.0-4.5, Cr 0.2-0.3, Ni 0.03-0.04, Zr 0.12-0.16, Hf 0.04-0.08, Re 0.03-0.05, La 0.04-0.08, Sm 0.02-0.03, Pr 0.015-0.025, Cu≤0.10, surplus are aluminium.

The manufacture method of aluminium alloy extrusions for car body: by above-mentioned alloying constituent, the furnace charge prepared is dropped into to smelting furnace, be heated to 760 ℃, treat that metal all melts, stir 45 minutes, detect alloying constituent and adjust; Then add refining agent to carry out refining, refining temperature is 730 ℃, and refining time is 20 minutes, after refining standing 30 minutes, start casting after skimming, and casting temp is 740 ℃, and casting speed is 80mm/min, and cooling water flow is 1800 L/min; Be warming up to 480 ℃ after casting, be incubated 12 hours, high wind air cooling to 220 ℃ again water-cooled to room temperature; Then ingot casting is heated to 510 ℃, uses the extrusion machine extrusion molding, extruding rate is 2mm/s; After air-cooled section bar surface temperature to 135 ℃, put into 3 ℃ of icy salt solutions and be down to rapidly below 50 ℃; The aluminium alloy extrusions that then will take out from salt solution first is warming up to 110 ℃ with 40 ℃/h, insulation 8h; Then be warming up to 175 ℃ with 30 ℃/h, insulation 8h; Be cooled to 60 ℃ with 50 ℃/h again, insulation 10h; Be warming up to 160 ℃ with 40 ℃/h again, insulation 5h, finally be cooled to 80 ℃ with 60 ℃/h, insulation 15h, and air cooling to the room temperature of coming out of the stove obtains aluminium alloy extrusions of the present invention.

Described refining agent preparation method is as follows: a. takes the raw material of following weight (kg): Repone K 10, sodium-chlor 8, aluminum fluoride 8, magnesium nitride 10, titanium boride 6, sodium aluminum fluoride 10, wollastonite 5, wilkinite 4; B. above-mentioned sodium aluminum fluoride, wollastonite, wilkinite were pulverized to 400 mesh sieves, after mixing, add 3% aluminium nitride, 0.8% Di(dioctylpyrophosphato) ethylene titanate, 1.5% nano-sized carbon, 1.5% Zinic stearas, 2000rpm high-speed stirring 15min, take out and dry, under 1500 ℃, calcine 2h, then shrend is cooling, grind, stand-by; C. by all the other each heating raw materials to 760 ℃, after its whole meltings, clarification 2h, be poured into water cold quenching by top clear liquor, obtains broken particle, and porphyrize is crossed 300 mesh sieves, stand-by; D. mixing of materials step b, c obtained stirs and obtains described refining agent.

The aluminium alloy extrusions of gained through the check mechanical property is: tensile strength 374Mpa, and yield strength is 258Mpa, elongation is 12.2%.

Claims (2)

1. a car body aluminium alloy extrusions, it is characterized in that: its each element consists of by mass percentage: Si 0.06-0.12, Fe 0.15-0.25, Mn 0.3-0.5, Mg 1.4-1.8, Zn 4.0-4.5, Cr 0.2-0.3, Ni 0.03-0.04, Zr 0.12-0.16, Hf 0.04-0.08, Re 0.03-0.05, La 0.04-0.08, Sm 0.02-0.03, Pr 0.015-0.025, Cu≤0.10, surplus are aluminium.

2. the manufacture method of aluminium alloy extrusions for car body as claimed in claim 1, it is characterized in that: by above-mentioned alloying constituent, the furnace charge prepared is dropped into to smelting furnace, be heated to 750-780 ℃, treat that metal all melts, stir 35-45 minute, detect alloying constituent and adjust; Then add refining agent to carry out refining, refining temperature is 720-740 ℃, and refining time is 15-25 minute, standing 20-30 minute after refining, start casting after skimming, casting temp is 730-750 ℃, casting speed is 70-80mm/min, and cooling water flow is 1600-1800 L/min; Be warming up to 460-480 ℃ after casting, the insulation 12-16 hour, the high wind air cooling to 180-220 ℃ again water-cooled to room temperature; Then ingot casting is heated to 490-510 ℃, uses the extrusion machine extrusion molding, extruding rate is 1-3mm/s; Air-cooled section bar surface temperature, after 120-150 ℃, is put into 0-3 ℃ of icy salt solution and is down to rapidly below 50 ℃; The aluminium alloy extrusions that then will take out from salt solution first is warming up to 110-120 ℃ with 30-40 ℃/h, insulation 6-8h; Then be warming up to 160-180 ℃ with 20-30 ℃/h, insulation 5-10h; Be cooled to 60-70 ℃ with 40-60 ℃/h again, insulation 8-12h; Be warming up to 150-170 ℃ with 30-40 ℃/h again, insulation 4-6h, finally be cooled to 80-90 ℃ with 50-60 ℃/h, insulation 10-15h, and air cooling to the room temperature of coming out of the stove obtains aluminium alloy extrusions of the present invention;

Described refining agent preparation method is as follows: a. takes the raw material of following weight part: Repone K 5-10, sodium-chlor 8-12, aluminum fluoride 5-10, magnesium nitride 8-12, titanium boride 4-8, sodium aluminum fluoride 10-15, wollastonite 4-8, wilkinite 3-5; B. above-mentioned sodium aluminum fluoride, wollastonite, wilkinite were pulverized to the 300-400 mesh sieve, after mixing, add the aluminium nitride of 2-3%, the Di(dioctylpyrophosphato) ethylene titanate of 0.5-1%, the nano-sized carbon of 1-2%, the Zinic stearas of 1-1.5%, 2000-3000rpm high-speed stirring 10-15min, take out and dry, under 1200-1600 ℃, calcine 2-3h, then shrend is cooling, grind, stand-by; C. by all the other each heating raw materials to 750-800 ℃, after its whole meltings, the clarification 1-2h, top clear liquor is poured into water to cold quenching, obtain broken particle, porphyrize is crossed the 200-400 mesh sieve, stand-by; D. mixing of materials step b, c obtained stirs and obtains described refining agent.