CN106591643A

CN106591643A - High mechanical property die-casting aluminum alloy and preparation method thereof

Info

Publication number: CN106591643A
Application number: CN201710026984.4A
Authority: CN
Inventors: 殷敏; 殷来大
Original assignee: DANYANG RONGJIA PRECISION MACHINERY Co Ltd
Current assignee: DANYANG RONGJIA PRECISION MACHINERY Co Ltd
Priority date: 2017-01-15
Filing date: 2017-01-15
Publication date: 2017-04-26

Abstract

The invention discloses a high mechanical property die-casting aluminum alloy and a preparation method thereof. Based on an existing die-casting aluminum alloy, a rare earth element La and a rare earth element Ce are added. The La is the hardest and densest metal in rare earth elements. The Ce is helpful to improve strength, tenacity, corrosion resistance and oxidation resistance. Meanwhile, the La and the Ce are surface-active elements, and capable of increasing wetting angles between aluminum melting bodies and particles, therefore, spreadability is improved, and aggregation and precipitation phenomena of the particles are effectively avoided. According to the high mechanical property die-casting aluminum alloy, nanometer aluminum powder is adopted to replace pure aluminum ingots, the prepared die-casting aluminum alloy has the advantages of being high in strength, small in thermal expansion coefficient and good in thermal stability. The proportion of alloy elements is adjusted, the preparation method of the die-casting aluminum alloy is optimized, effective alloy designing is carried out, the comprehensive mechanical property of the die-casting aluminum alloy is improved, and the application field of the die-casting aluminum alloy is widened.

Description

A kind of strong mechanical performance pack alloy and preparation method thereof

Technical field

The invention belongs to metal material field, refers in particular to a kind of strong mechanical performance pack alloy and preparation method thereof.

Background technology

Current aluminium alloy compression casting technology constantly develops, and increasing stress part employs aluminium alloy compression casting production, because This most of demanding party all proposes the requirement of the mechanical properties such as tensile strength to aluminum alloy die casting.The pressure industrially applied at present Cast aluminium alloy mainly has following several big series：Al-Si, Al-Mg, Al-Si-Cu, Al-Si-Mg etc., pack alloy with compared with High specific strength, etch resistant properties and good casting character, processing characteristics and recyclability and excellent electrical and thermal conductivity Can, it is widely used in the fields such as automobile, Aero-Space and electrical equipment industry.With the industrial expansions such as automobile, aluminum alloy die casting Yield increased with nearly 13% speed every year, its yield accounts for more than the 75% of all die casting yield, and aluminium alloy compression casting Part develops towards high intensity, high-quality direction.

At present, pack alloy is widely used, but the die casting high to mechanical property requirements for car body etc., only by existing Pack alloy is difficult to meet demand.

The content of the invention

To solve an above-mentioned difficult problem, the present invention proposes a kind of strong mechanical performance pack alloy and preparation method thereof, obtained Pack alloy the characteristics of there is high ductibility, high intensity, excellent corrosion resistance.

The composition of pack alloy of the present invention and the percentage by weight for respectively constituting are：

Si 4.5-8.5wt%,

Mg 1.1-1.8wt%,

Cu 2.5-3.6wt%,

Ti 0.1-0.2wt%,

Fe 0.2-0.8wt%,

La 0.01-0.03wt%

Ce 0.02-0.04wt%,

Al surpluses.

The preparation method of the pack alloy is as follows：

(1) prepare raw material：Nanometer aluminium powder, Al-Si alloys, made of Al-Cu alloy, Al-Fe alloys, Cu-Mg alloys, Al-Ti Alloy and mischmetal；

(2) pretreatment：Raw material is dried into process, baking temperature is 90-130 DEG C, and drying time is 0.5-4h, together When preheat graphite crucible, temperature is 450-500 DEG C；

(3) it is thick to refine：Al-Fe alloys, Cu-Mg alloys, Al-Si alloys, made of Al-Cu alloy, Al-Ti alloys are added into graphite first In crucible, 650 DEG C are warming up to, are stirred continuously up to alloy and are all molten into melt, be incubated 8min-12min, be warming up to 900 DEG C, Nanometer aluminium powder, La and Ce are added in graphite pincers pot bottom, is stirred continuously until fusing, standing 1-2h, obtain thick aluminium metallurgy alloy and melt Body；

(4) refine：Thick aluminium metallurgy alloy melt is carried out into refine by refining agent, refining aluminium alloy melt is obtained；

(6) die casting：Mould is preheated, preheating temperature is 220 DEG C, refining aluminium alloy melt is lowered the temperature, works as refined aluminum When alloy melt temperature is down to 620～650 DEG C, by the die cavity of refining aluminium alloy die casting to mould, filling velocity is 0.5-1m/ S, pressure is 80-95MPa, and die casting terminates rear pressurize, and the dwell time is 2-5s, and pack alloy, pack alloy are taken out in die sinking Composition and percentage by weight be：Si is 4.5-8.5wt%, and Mg is 1.1-1.8wt%, and Cu is 2.5-3.6wt%, and Ti is 0.1- 0.2wt%, Fe are 0.2-0.8wt%, and La is 0.01-0.03wt%, and Ce is 0.02-0.04wt%, Al surpluses.

The particle diameter of the nanometer aluminium powder is 50-100nm.

The graphite pincers pot is used under vacuo.

The refining agent is one or more in rare gas He, Ar and Ne.

The mischmetal is La and Ce.

The present invention compared with prior art, with advantages below：

1. the present invention is on the basis of existing pack alloy, adds lanthanide-indueed shift, Ce be favorably improved intensity, Toughness, corrosion resistance and non-oxidizability, while La and Ce are surface active elements, can make the angle of wetting between aluminum melt and particle Increase, so as to improve spreadability, is prevented effectively from aggregation of particles and deposited phenomenon；

2. the present invention substitutes fine aluminium ingot using nanometer aluminium powder, and the pack alloy of preparation has intensity height, thermal coefficient of expansion The characteristics of little, heat stability is good；

3. the present invention have adjusted the ratio of alloying element, carries out effective alloy design, improves the comprehensive of pack alloy Mechanical property is closed, the application of pack alloy has been widened.

Specific embodiment

The present invention is further supplemented and described with reference to specific embodiment.

Embodiment 1

(1) prepare raw material：The nanometer aluminium powder of particle diameter 50-100nm, Al-Si alloys, made of Al-Cu alloy, Al-Fe alloys, Cu-Mg alloys, Al-Ti alloys, La and Ce；

(2) pretreatment：Raw material is dried into process, baking temperature is 90 DEG C, and drying time is 4h, while in vacuum Under the conditions of preheat graphite crucible, temperature is 500 DEG C；

(4) refine：First He is preheated, preheating temperature is 150 DEG C, when graphite pincers pot temperature is 750 DEG C, He is blown into slightly Refine is carried out in aluminium metallurgy alloy melt, refining time is 40min, and 20min is stood after refine, obtains refining aluminium alloy melt；

(5) die casting：Mould is preheated, preheating temperature is 220 DEG C, refining aluminium alloy melt is lowered the temperature, works as refined aluminum When alloy melt temperature is down to 620 DEG C, by the die cavity of refining aluminium alloy die casting to mould, filling velocity is 1m/s, and pressure is 95MPa, die casting terminate rear pressurize, and the dwell time is 2s, and pack alloy A1, the composition and weight of pack alloy A1 are taken out in die sinking Measuring percentage ratio is：Si is 5wt%, and Mg is 1.3wt%, and Cu is 2.6wt%, and Ti is 0.1wt%, and Fe is 0.2wt%, and La is 0.01wt%, Ce are 0.02wt%, Al surpluses.

Embodiment 2

Substantially the same manner as Example 1, its difference is, in step (5)：Prepared pack alloy A2, die casting aluminium are closed The composition and percentage by weight of golden A2 be：Si is 8.5wt%, and Mg is 11.8wt%, and Cu is 3.6wt%, and Ti is 0.2wt%, Fe For 0.8wt%, La is 0.03wt%, and Ce is 0.04wt%, Al surpluses.

Embodiment 3

Substantially the same manner as Example 1, its difference is, in step (5)：Prepared pack alloy A3, die casting aluminium are closed The composition and percentage by weight of golden A3 be：Mg is 1.2wt%, and Cu is 2.5wt%, and Ti is 0.1wt%, and Fe is 0.2wt%, and Ce is 0.03wt%, Al surplus.

Embodiment 4

Substantially the same manner as Example 1, its difference is, in step (5)：Baking temperature is 120 DEG C, and drying time is 3h；The composition and percentage by weight of prepared pack alloy A4, pack alloy A4 be：Si is 6wt%, and Mg is 1.1wt%, Cu For 2.5wt%, Ti is 0.2wt%, and Fe is 0.3wt%, and La is 0.03wt%, Al surpluses.

Embodiment 5

Substantially the same manner as Example 1, its difference is, in step (5), pack alloy A5 is obtained, and die casting aluminium is closed The composition and percentage by weight of golden A5 be：Si is 7wt%, and Mg is 1.2wt%, and Cu is 3wt%, and Fe is 0.8wt%, and La is 0.03wt%, Ce are 0.03wt%, Al surpluses.

Embodiment 6

(4) refine：Prepare refining agent：Sodium Chloride, potassium chloride, hexafluoro sodium aluminate, sodium nitrate, sodium carbonate, lanthanum carbonate, oxidation Lanthanum, Cericammoniumsulfate, cerium fluoride, in terms of weight fraction, weigh 10 parts of Sodium Chloride, 10 parts of potassium chloride, 20 parts of hexafluoro sodium aluminate, nitric acid 10 parts of sodium, 10 parts of sodium carbonate, 2 parts of lanthanum carbonate, 2 parts of lanthana, 2 parts of Cericammoniumsulfate, 2 parts of cerium fluoride, by the Sodium Chloride for weighing, chlorine Change potassium, hexafluoro sodium aluminate, sodium nitrate, sodium carbonate are respectively placed in drying baker, 80 DEG C of baking temperature, and 4h, will weigh drying time 2 parts of lanthanum carbonate, 2 parts of lanthana, 2 parts of Cericammoniumsulfate, 2 parts of cerium fluoride be placed in other drying baker, 120 DEG C of baking temperature, Drying time, 2h, used screen filtration after drying, and screen cloth is 400 mesh, raw material is put in cone-type mixer after screen filtration and is mixed Stirring is closed, 1h is mixed under conditions of 50 DEG C, after mixing and stirring, cone blender is opened, stood cooling, be down to After room temperature, mixture is placed on cold press the round pie refining agent for being pressed into diameter 20cm, thickness 1cm, is put in drying receptacle Preserve；Round pie refining agent is weighed, round pie refining agent is 1 with the weight ratio of aluminium alloy melt:100, when aluminum melt temperature is When 690 DEG C, round pie refining agent is slowly introducing in aluminium alloy melt by aluminium alloy spray refining machine, when round pie refining agent All it is passed in aluminium alloy melt, takes out aluminium alloy spray refining machine, carry out refine, refining time is 3h, after refine terminates, The scum silica frost of aluminium melt surface is removed by Cinder Machine, insulation after removing stands 1h；

(5) die casting：Mould is preheated, preheating temperature is 220 DEG C, refining aluminium alloy melt is lowered the temperature, works as refined aluminum When alloy melt temperature is down to 620 DEG C, by the die cavity of refining aluminium alloy die casting to mould, filling velocity is 1m/s, and pressure is 95MPa, die casting terminate rear pressurize, and the dwell time is 2s, and pack alloy A6, the composition and weight of pack alloy A6 are taken out in die sinking It is 8wt% that amount percentage ratio is Si, and Cu is 3.1wt%, and Ti is 0.2wt%, and Fe is 0.4wt%, and La is 0.02wt%, and Ce is 0.03wt%, Al surplus；

Embodiment 7

Substantially the same manner as Example 6, its difference is, in step (4), after insulation stands 1h；First will with ear washing bulb Chip in ceramic foam filter is removed, and then preheats the ceramic foam filter of different pore size, preheating temperature 100 DEG C, preheating time 1h, to remove steam, by ceramic foam filter by aperture from big to small successively arranged orthogonal in running gate system Cross gate in, in step (5), 0.5h is preheated to die casting before filtration, preheating temperature be 220 DEG C, by refined aluminum Alloy melt is lowered the temperature, and when refining aluminium alloy melt temperature is down to 620 DEG C, refining aluminium alloy is filtered, and during filtration, aluminium alloy melts Body flows through 30ppi ceramic foam filters, 25ppi ceramic foam filters, 20ppi ceramic foam filters, 15ppi bubbles successively Foam ceramic filter；After filtration, in the die cavity of mould, filling velocity is 1m/s, and pressure is 95M Pa, after die casting terminates for die casting Pressurize, dwell time are 2s, and pack alloy A7 is obtained, and the composition and percentage by weight of pack alloy A7 are：Si is 8.5wt%, Mg are 1.4wt%, and Cu is 3.6wt%, and Ti is 0.2wt%, and Fe is 0.6wt%, and La is 0.02wt%, and Ce is 0.03wt%, Al surplus, is obtained pack alloy A7.

On pack alloy A1-A7 prepared by embodiment 1-7 and market, routine pack alloy YL112, YL113 are carried out Comprehensive mechanical property tests (Testing Tensile Strength at Elevated Temperature, room temperature tensile strength, yield strength)

Table 1：Pack alloy A1-A7 and pack alloy YL112, the resultant force of pack alloy YL113

Learn the performance test results

	Tensile strength (MPa)	Yield strength (MPa)	Percentage elongation (%)	Brinell hardness (HBS)
					A1	310	200	2.1	90
A2	325	250	1.8	100
					A3	315	180	2.2	105
A4	305	175	2.4	110
					A5	280	225	1.5	95
A6	295	235	3	90
					A7	308	258	2	95
YL112	240	165	1	85
					YL113	230	170	1	80

The pack alloy that present invention preparation be can be seen that according to the data in table 1 has higher tensile strength, surrender Intensity, percentage elongation and Brinell hardness, comprehensive mechanical property are remarkably reinforced, and the tensile strength of wherein pack alloy A2 reaches 325MPa, yield strength reach 250MPa, and Brinell hardness reaches 100HBS, and elongation percentage reaches 1.8, and the mechanical property much surpasses The YL112 and YL113 commonly used on market is crossed, is particularly suited for the pack alloy application required with high intensity.

Many other changes and remodeling can be made without departing from the spirit and scope of the present invention.It should be appreciated that the present invention is not It is limited to specific embodiment, the scope of the present invention is defined by the following claims.

Claims

1. a kind of strong mechanical performance pack alloy, it is characterised in that the weight of the composition of the pack alloy and each composition Percentage ratio is：

2. a kind of preparation method of strong mechanical performance pack alloy, it is characterised in that the preparation method of the pack alloy It is as follows：

(1) prepare raw material：Nanometer aluminium powder, Al-Si alloys, made of Al-Cu alloy, Al-Fe alloys, Cu-Mg alloys, Al-Ti alloys And mischmetal；

(2) pretreatment：Raw material is dried into process, baking temperature is 90-130 DEG C, and drying time is 0.5-4h, while in advance Hot graphite crucible, temperature are 450-500 DEG C；

(3) it is thick to refine：Al-Fe alloys, Cu-Mg alloys, Al-Si alloys, made of Al-Cu alloy, Al-Ti alloys are added into graphite crucible first In, 650 DEG C are warming up to, are stirred continuously up to alloy and are all molten into melt, be incubated 8min-12min, be warming up to 900 DEG C, in stone Ink pincers pot bottom adds nanometer aluminium powder, La and Ce, is stirred continuously until fusing, stands 1-2h, obtain thick aluminium metallurgy alloy melt；

(4) refine：First refining agent is preheated, preheating temperature is 150-250 DEG C, when graphite pincers pot temperature is 650-750 DEG C, will Refining agent is blown in thick aluminium metallurgy alloy melt carries out refine, and refining time is 20-40min, stands 20min, obtain after refine Refining aluminium alloy melt；

(5) die casting：Mould is preheated, preheating temperature is 220 DEG C, refining aluminium alloy melt is lowered the temperature, works as refining aluminium alloy When melt temperature is down to 620～650 DEG C, by the die cavity of refining aluminium alloy die casting to mould, filling velocity is 0.5-1m/s, pressure Power is 80-95MPa, and die casting terminates rear pressurize, and the dwell time is 2-5s, and pack alloy pressure, the group of cast aluminium alloy are taken out in die sinking Into and percentage by weight be：Si is 4.5-8.5wt%, and Mg is 1.1-1.8wt%, and Cu is 2.5-3.6wt%, and Ti is 0.1- 0.2wt%, Fe are 0.2-0.8wt%, and La is 0.01-0.03wt%, and Ce is 0.02-0.04wt%, Al surpluses.

3. a kind of preparation method of strong mechanical performance pack alloy as claimed in claim 2, it is characterised in that the nanometer The particle diameter of aluminium powder is 50-100nm.

4. a kind of preparation method of strong mechanical performance pack alloy as claimed in claim 2, it is characterised in that the graphite Pincers pot is used under vacuo.

5. a kind of preparation method of strong mechanical performance pack alloy as claimed in claim 2, it is characterised in that the refine Agent is one or more in rare gas He, Ar and Ne.

6. a kind of preparation method of strong mechanical performance pack alloy as claimed in claim 2, it is characterised in that the mixing Rare earth is La and Ce.