CN103469020A - Low-expansion aluminum alloy section material and preparation method thereof - Google Patents

Abstract

The invention discloses a low-expansion aluminum alloy section material and a preparation method thereof. The low-expansion aluminum alloy section material comprises, by mass, 4.4-5.2% of Si, 1.2-1.6% of Cu, 0.4-0.8% of Mg, 0.3-0.5% of Zn, 0.2-0.3% of Mn, 0.15-0.25% of Be, 0.08-0.14% of Mo, 0.05-0.1% of V, 0.04-0.08% of Tc, 0.03-0.05% of Fe, 0.05-0.08% of Y, 0.03-0.06% of Pr, 0.02-0.04% of Tb, and the balance Al. The aluminum alloy section material prepared in the invention has the advantages of high compactness, low expansion, small hot cracking tendency, high strength, excellent mechanical properties under high temperatures, good weldability and machinability, and wide application field.

Description

A kind of low bulk aluminium alloy extrusions and manufacture method thereof

Technical field

The present invention relates to a kind of low bulk aluminium alloy extrusions and manufacture method thereof, 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 the high characteristics such as reclaiming, be widely used in the fields such as automobile, machinofacture, boats and ships, building, finishing.The character such as piston of automobile engine sustained ring, vehicle bearing alloy, computer hard disk substrate etc. all need the rate of expansion of aluminium alloy low, good stability of the dimension, intensity height, can work for a long time.

Summary of the invention

In order to address the above problem ,the invention provides a kind of low bulk aluminium alloy extrusions and manufacture method thereof, reduce the rate of expansion of aluminium alloy.

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

A kind of low bulk aluminium alloy extrusions, its each element consists of by mass percentage: Si 4.4-5.2, Cu 1.2-1.6, Mg 0.4-0.8, Zn 0.3-0.5, Mn 0.2-0.3, Be 0.15-0.25, Mo 0.08-0.14, V 0.05-0.1, Tc 0.04-0.08, Fe 0.03-0.05, Y 0.05-0.08, Pr 0.03-0.06, Tb 0.02-0.04, surplus are aluminium.

The manufacture method of low bulk aluminium alloy extrusions, drop into smelting furnace by above-mentioned alloying constituent by the furnace charge prepared, and is heated to 765-785 ℃, treats that metal all melts, and stirs 30-40 minute, detects alloying constituent and adjust; Then add refining agent to carry out refining, refining temperature is 715-735 ℃, and refining time is 18-24 minute, standing 20-30 minute after refining, start casting after skimming, casting temp is 720-740 ℃, casting speed is 60-80mm/min, and cooling water flow is 1650-1750 L/min; Be warming up to 450-470 ℃ after casting, insulation 12-16 hour, then be cooled to 320-340 ℃, insulation 5-10 hour, then be cooled to 160-190 ℃, insulation 4-6 hour; Then ingot casting is heated to 490-510 ℃, uses the extrusion machine extrusion molding, extruding rate is 2-3mm/s; Aluminium alloy extrusions after extrusion molding first is warming up to 320-350 ℃ with 70-80 ℃/h, insulation 1-1.5h, be warming up to 490-520 ℃ with 80-100 ℃/h again, insulation 50-60min, then be cooled to rapidly 110-130 ℃ with 240-280 ℃/h, then put into 0-5 ℃ of icy salt solution and be down to rapidly below 50 ℃; The aluminium alloy extrusions that then will take out from salt solution first is warming up to 150-180 ℃ with 40-60 ℃/h, insulation 8-12h; Then be cooled to 80-90 ℃ with 30-50 ℃/h, insulation 4-7h; Be warming up to 160-190 ℃ with 40-50 ℃/h again, insulation 3-6h, finally be cooled to 70-80 ℃ with 50-60 ℃/h, insulation 5-10h, 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:

The high compact and low-expension of the aluminium alloy extrusions that the present invention makes, hot cracking tendency is little, and intensity is high, the mechanical behavior under high temperature excellence, welding and machinability are good, and Application Areas is extensive.

Embodiment

A kind of low bulk aluminium alloy extrusions, its each element consists of by mass percentage: Si 4.4-5.2, Cu 1.2-1.6, Mg 0.4-0.8, Zn 0.3-0.5, Mn 0.2-0.3, Be 0.15-0.25, Mo 0.08-0.14, V 0.05-0.1, Tc 0.04-0.08, Fe 0.03-0.05, Y 0.05-0.08, Pr 0.03-0.06, Tb 0.02-0.04, surplus are aluminium.

The manufacture method of low bulk aluminium alloy extrusions, drop into smelting furnace by above-mentioned alloying constituent by the furnace charge prepared, and is heated to 780 ℃, treats that metal all melts, and stirs 30 minutes, detects alloying constituent and adjust; Then add refining agent to carry out refining, refining temperature is 720 ℃, and refining time is 22 minutes, after refining standing 25 minutes, start casting after skimming, and casting temp is 730 ℃, and casting speed is 70mm/min, and cooling water flow is 1700 L/min; Be warming up to 460 ℃ after casting, be incubated 14 hours, then be cooled to 330 ℃, be incubated 8 hours, then be cooled to 180 ℃, be incubated 5 hours; Then ingot casting is heated to 505 ℃, uses the extrusion machine extrusion molding, extruding rate is 2.5mm/s; Aluminium alloy extrusions after extrusion molding first is warming up to 340 ℃ with 80 ℃/h, insulation 1h, then be warming up to 510 ℃ with 90 ℃/h, insulation 50min, then be cooled to rapidly 120 ℃ with 260 ℃/h, then put into 2 ℃ 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 160 ℃ with 50 ℃/h, insulation 10h; Then be cooled to 80 ℃ with 40 ℃/h, insulation 6h; Be warming up to 180 ℃ with 50 ℃/h again, insulation 4h, finally be cooled to 70 ℃ with 60 ℃/h, insulation 7h, 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 6, magnesium nitride 10, titanium boride 6, sodium aluminum fluoride 12, wollastonite 6, wilkinite 4; B. above-mentioned sodium aluminum fluoride, wollastonite, wilkinite were pulverized to 300 mesh sieves, after mixing, add 2% aluminium nitride, 0.6% Di(dioctylpyrophosphato) ethylene titanate, 1% nano-sized carbon, 1.5% Zinic stearas, 3000rpm high-speed stirring 10min, take out and dry, under 1450 ℃, calcine 2h, then shrend is cooling, grind, stand-by; C. by all the other each heating raw materials to 780 ℃, after its whole meltings, clarification 1h, 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 464Mpa, and yield strength is 346Mpa, and elongation is 9.8%, and the thermal expansivity under 250-400 ℃ is 6.8 * 10 ^-6-7.2 * 10 ^-6between.

Claims (2)

1. a low bulk aluminium alloy extrusions, it is characterized in that: its each element consists of by mass percentage: Si 4.4-5.2, Cu 1.2-1.6, Mg 0.4-0.8, Zn 0.3-0.5, Mn 0.2-0.3, Be 0.15-0.25, Mo 0.08-0.14, V 0.05-0.1, Tc 0.04-0.08, Fe 0.03-0.05, Y 0.05-0.08, Pr 0.03-0.06, Tb 0.02-0.04, surplus are aluminium.

2. the manufacture method of low bulk aluminium alloy extrusions 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 765-785 ℃, treat that metal all melts, stir 30-40 minute, detect alloying constituent and adjust; Then add refining agent to carry out refining, refining temperature is 715-735 ℃, and refining time is 18-24 minute, standing 20-30 minute after refining, start casting after skimming, casting temp is 720-740 ℃, casting speed is 60-80mm/min, and cooling water flow is 1650-1750 L/min; Be warming up to 450-470 ℃ after casting, insulation 12-16 hour, then be cooled to 320-340 ℃, insulation 5-10 hour, then be cooled to 160-190 ℃, insulation 4-6 hour; Then ingot casting is heated to 490-510 ℃, uses the extrusion machine extrusion molding, extruding rate is 2-3mm/s; Aluminium alloy extrusions after extrusion molding first is warming up to 320-350 ℃ with 70-80 ℃/h, insulation 1-1.5h, be warming up to 490-520 ℃ with 80-100 ℃/h again, insulation 50-60min, then be cooled to rapidly 110-130 ℃ with 240-280 ℃/h, then put into 0-5 ℃ of icy salt solution and be down to rapidly below 50 ℃; The aluminium alloy extrusions that then will take out from salt solution first is warming up to 150-180 ℃ with 40-60 ℃/h, insulation 8-12h; Then be cooled to 80-90 ℃ with 30-50 ℃/h, insulation 4-7h; Be warming up to 160-190 ℃ with 40-50 ℃/h again, insulation 3-6h, finally be cooled to 70-80 ℃ with 50-60 ℃/h, insulation 5-10h, 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.