CN1477221A - High-temp, creeping resistant compression casting magnesium alloy - Google Patents

High-temp, creeping resistant compression casting magnesium alloy Download PDF

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Publication number
CN1477221A
CN1477221A CNA031270638A CN03127063A CN1477221A CN 1477221 A CN1477221 A CN 1477221A CN A031270638 A CNA031270638 A CN A031270638A CN 03127063 A CN03127063 A CN 03127063A CN 1477221 A CN1477221 A CN 1477221A
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umber
high temperature
weight
novel anti
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CN100424209C (en
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骏 侯
侯骏
刘耀辉
佟国栋
刘海峰
孟赢
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FAW Group Corp
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FAW Group Corp
Faw Foundry Co Ltd
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Abstract

The present invention relates to a new-type high-temp. creep resistant die cast magnesium alloy. It utilizes the adoption of Mg-rare earth intermediate alloy to not only obtain the Mg-Al-Zn-Y(Nd) alloy with excellent creep resistance, its composition includes (by weight portion ratio) Al 8.0-9.5, Zn 0.45-0.90 and Y(Nd) 0.5-3.0, but also the residual portion is formed from Mg and inevitable impurity.

Description

Novel anti high temperature creep diecast magnesium alloy
Technical field:
The present invention relates to a kind of diecast magnesium alloy, particularly relate to a kind of novel anti high temperature creep diecast magnesium alloy.Mainly be the lightweight magnesium alloy member that uses as auto parts, and be the Hpdc magnesium alloy.
Background technology:
Magnesium is as the lightest engineering metal material (density 1.8g/cm 3Be 2/3 of aluminium, steel 1/4), has light specific gravity, specific tenacity and specific rigidity height, damping and amortization and machinability are good, thermal conductivity is good, the electromagnetic shielding ability is strong and vibration damping is good and be easy to the character of a series of uniquenesses such as reclaiming, satisfied aviation, space flight, Hyundai Motor industry is to loss of weight, requirements of saving energy, and alternative engineering plastics are to satisfy 3C (computer, communication, consumer electronics) product is light, thin, miniaturization, the requirement of high integration and environmental protection aspect, become the preferred material of Hyundai Motor and 3C industry, be described as " the green engineering material of 21 century ".But also exist at present the difficult point that awaits the technical elements that solves in a large number and restricting the further application of diecast magnesium alloy parts on automotive industry, this mainly shows the insufficient strength height, still can not be used on the important structure parts, the high temperature use properties obviously descends; More than two aspects can not get not solving, magnesium alloy just can not obtain widely to use in automotive industry.
The high temperature creep-resisting magnesium alloy of having developed at present mainly contains AE42 alloy (diecast magnesium alloy, U.S. DOW company, cost height, melt treatment complexity, manufacturability is poor, creep-resistant property is good), AS41 and AS21 alloy (diecast magnesium alloy, germany volkswagen company, manufacturability is poor, creep-resistant property is general), AC52 alloy (diecast magnesium alloy, AM General company, the test assessment stage, do not see and carry out industrial application), (the sand mold casting magnesium alloy contains Y and Nd to WE43, has the good high-temperature performance, the cost height, the melt treatment complexity), but yet there are no about containing the creep resistance diecast magnesium alloy of Y and Nd.
Summary of the invention:
The objective of the invention is to be to provide a kind of novel anti high temperature creep diecast magnesium alloy; so low melting point and Mg-Y are cheaply being adopted in the essential distinction of the one-tenth assignment system of this series novel alloy and the WE43 alloy of the mishmetal preparation of adopting rich Y; the Nd master alloy is realized the interpolation of Y and Nd; utilize Y and Nd solid solubility in magnesium alloy bigger; make full use of the creep-resistant property that solution strengthening improves magnesium alloy; and greatly reduce the complexity of cost and melt treatment; thereby the low cost of making; the mass-producing commercial production becomes possibility; and satisfying in the automotive industry requirement to material cost, its cost is the highest can not to surpass 15% of AZ91 magnesium alloy cost.Its good manufacturability is easy to promote the use of, and satisfies at 150 ℃ steady operation under the 50MPa condition.
Technical scheme of the present invention is achieved in that the composition of novel anti high temperature creep diecast magnesium alloy is (by ratio of weight and the number of copies): Al 8.0-9.5, and Zn 0.45-0.90, Y 0.5-3.0, and remainder is made up of Mg and unavoidable impurities.
The present invention also provides a kind of novel anti high temperature creep diecast magnesium alloy, its composition (by ratio of weight and the number of copies): Al 8.0-9.5, and Zn 0.45-0.90, Nd 0.5-3.0, and remainder is made up of Mg and unavoidable impurities.
Processing step of the present invention is as follows: comprise the preparation and the melting of alloy;
(1) preparation of alloy: comprise following two kinds of methods;
Method 1:
Calculate the parts by weight that each raw material needs according to the composition that adopts, the employing raw material is: (composition should meet the regulation of ASTM B93/94 to the AZ91HP alloy, Mn content>0.3% wherein, its composition is pressed Mg 90.3, Al 9, and Zn 0.7 calculates), pure Al (calculate umber 1.05), Mg-Y (Nd) master alloy (calculates 1.03 of umber, except that rare earth element, its Si, Mn, Fe, Ni, Cu and other impurity should meet the corresponding composition regulation of AZ91HP alloy among the ASTM B93/94, its composition is pressed Mg 19.8, and Y 20, and Mn 0.2,), electrolysis Zn (calculate umber 1.03).
Method 2;
Calculate the parts by weight that each raw material needs according to the composition that adopts, the employing raw material is: magnesium ingot (calculates 1.08 of umber, Mg content is counted by weight greater than 99.9), pure Al (calculate umber 1.02), electrolysis Zn (calculate umber 1.01), Al-Mn alloy, Mg-Y (Nd) master alloy (calculate 1.03 of umber, except that rare earth element, its Si, Mn, Fe, Ni, Cu and other impurity should meet the corresponding composition regulation of AZ91HP alloy among the ASTM B93/94, its composition is pressed Mg 19.8, and Y 20, and Mn 0.2 calculates).
(2) melting of alloy:
1. the raw material that method 1 is configured adds in the following order: with the AZ91HP alloy, and electrolysis Zn, pure Al after the mixing is warming up to it 685-690 ℃ of fusing, is promptly feeding mixed gas protectedly more than 420 ℃, and its ratio of gas mixture is: N 2+ 0.002-0.005%SF 6, add Mg-Y (Nd) master alloy until completely melted, static 30 minutes, keep melt temperature at 680-690 ℃, get final product die casting or reduce to 620-630 ℃ of cast alloy cast ingot.
2. the raw material that method 2 is configured, remove Mg-Y (Nd) master alloy, all the other raw materials are pressed the general melting program melting of AZ91HP alloy, after treating that alloy is finished refining, keep melt temperature at 690-710 ℃, add Mg-Y (Nd) master alloy, and logical Ar stirred 20 minutes, static to 690 ℃ of die casting or reduce to 620-630 ℃, the cast alloy cast ingot.
Positively effect of the present invention is: its good manufacturability is easy to promote the use of, and satisfies at 150 ℃, steady operation under the 50MPa condition, the highest 15% of the AZ91HP alloy that is no more than of its cost.And prove its effect by following experimental example:
Experimental example 1:
Compare test with alloy of the present invention and AZ91 HP alloy at room temperature tensile strength, wherein 1# is the AZ91HP alloy, and 2# and 3# are the alloy of dosing different ratios Y of the present invention, and 4# and 5# dose the alloy of different ratios Nd for the present invention.The alloy tensile strength at room temperature of two kinds of different components is apparently higher than the AZ91HP alloy as can be seen by the test-results of Fig. 3, and the tested alloys composition is as shown in table 1.
Table 1 tested alloys composition
The alloy sequence number Chemical ingredients Wt%
????Mg ????Al ????Zn ????Y ????Nd ????Mn ????Si ???Cu ???Ni ???Fe Other
????1 ????Bal ????8.85 ????0.86 ????- ????- ????0.32 ????0.03 ???≤ ??????0.008 ???≤ ??????0.008 ???≤ ??????0.004 ???≤ ??????0.01
????2 ????Bal ????9.02 ????0.78 ????0.57 ????- ????0.26 ????0.035 ???≤ ??????0.00 ???≤ ??????0.008 ???≤ ??????0.004 ???≤ ??????0.01
????3 ????Bal ????8.54 ????0.65 ????0.78 ????- ????0.29 ????0.04 ???≤ ??????0.00 ???≤ ??????0.008 ???≤ ??????0.004 ???≤ ??????0.01
????4 ????Bal ????8.26 ????0.64 ????- ????0.48 ????0.35 ????≤ ????????0.05 ???≤ ??????0.015 ???≤ ??????0.001 ???≤ ??????0.004 ???≤ ??????0.01
????5 ????Bal ????8.35 ????0.69 ????- ????0.76 ????0.20 ????≤ ????????0.05 ???≤ ??????0.015 ???≤ ??????0.001 ???≤ ??????0.004 ???≤ ??????0.01
Can prove by Fig. 3, the AZ91HP alloy tensile strength at room temperature of 1# is 220MPa, 2# and 3# dose respectively 0.57 and the alloy tensile strength at room temperature of 0.78Y then be 272MPa and 275MPa, 4# and 5# dose respectively 0.48 and the alloy tensile strength at room temperature of 0.76Nd be 264 and 274MPa.
Experimental example 2:
Tested alloys in the table 1 at 150 ℃, is carried out the creep resistance test under the 50MPa, its test-results as shown in Figure 4.The creep-resistant property of 2# of the present invention and 3# and 4# and 5# alloy is significantly better than the AZ91HP alloy, and the creep compliance of its 100h has only the 1/15-1/20 of AZ91HP alloy.The creep-resistant property of 2# and 3# alloy is a little more than the alloy of 4# and 5#, because the difference of the creep resistance of the alloy of different ratios is little, so that some creep curve overlaps.
Cost analysis
According to the cost estimating to alloy of the present invention, visible novel alloy cost of the present invention has increased about 8% with AZ91 alloy phase ratio as shown in Figure 5.
Description of drawings
Fig. 1 is the ambient temperature mechanical properties sample
Fig. 2 is creep test sample
Fig. 3 is the contrast of magnesium alloy materials of the present invention and AZ91HP alloy room temperature tensile strength.
Fig. 4 is in creep test, the contrast of magnesium alloy materials of the present invention and AZ91HP alloy creep-resistant property.
Fig. 5 is the cost estimating of alloy of the present invention.
Embodiment:
The invention will be further described below in conjunction with accompanying drawing:
Embodiment 1:
A kind of novel anti high temperature creep diecast magnesium alloy, its alloy ingredient comprises Al 9.0 by ratio of weight and the number of copies, and Zn 0.45, and Y 0.5, and Mn 0.2, and remainder is made up of Mg and unavoidable impurities.The adding of Mn mainly is in order to improve corrosion resistance of alloy, if the parts by weight of Mn surpass 0.4, might form the compound that influences creep-resistant property, and the parts by weight of Mn to be lower than 0.1, then corrosion resisting property not being had benefit.The preparation of this composition alloy and the process of melting may further comprise the steps:
(1) preparation of alloy
Novel alloy can adopt following two kinds of methods preparation,
Method 1:
The employing raw material is: (composition should meet the regulation of ASTM B93/94 to the AZ91HP alloy, Mn content>0.3% wherein), pure Al, Mg-Y (Nd) master alloy is (except that rare earth element, its Si, Mn, Fe, Ni, Cu and other impurity should meet the corresponding composition regulation of AZ91HP alloy among the ASTM B93/94), electrolysis Zn, calculate each raw-material consumption according to the composition proportion that adopts, wherein pure Al takes by weighing by 1.05 of calculated weight umber, the Mg-Y master alloy takes by weighing by 1.03 of calculated weight umber, and Zn takes by weighing by 1.03 of calculated weight umber;
Method 2;
The employing raw material is: and magnesium ingot (Mg content is counted by weight greater than 99.9), pure Al, electrolysis Zn, Al-Mn alloy, Mg-Y master alloy (except that rare earth element, its Si, Mn, Fe, Ni, Cu, other impurity should meet the corresponding composition regulation of AZ91HP alloy among the ASTM B93/94).Calculate each raw-material consumption according to the composition proportion that adopts, wherein magnesium ingot takes by weighing by 1.08 of calculated weight umber, pure Al takes by weighing by 1.02 of calculated weight umber, and the Mg-Y master alloy takes by weighing by 1.03 of calculated weight umber, and Zn takes by weighing by 1.01 of calculated weight umber;
(2) melting of alloy
Dispose raw material by method 1:
Raw-material addition sequence is the AZ91HP alloy, electrolysis Zn, and pure Al is warming up to 685-690 ℃ of fusing, is promptly feeding mixed gas protected (blending ratio: N more than 420 ℃ 2+ 0.002-0.005%SF 6), add Mg-Y (Nd) master alloy until completely melted, static 30 minutes, keep melt temperature at 680-690 ℃, get final product die casting or reduce to 620-630 ℃ of cast alloy cast ingot.
Dispose raw materials by method 2:
Remove Mg-Y (Nd) master alloy, all the other raw materials are pressed the general melting program melting of AZ91HP alloy, after treating that alloy is finished refining, keep melt temperature at 690-710 ℃, add Mg-Y (Nd) master alloy, and logical Ar stirred 20 minutes, should try one's best without insulating covering agent (unless bath surface ignition) in this stage.Static to 690 ℃ of die casting or reduce to 620-630 ℃, the cast alloy cast ingot.
Embodiment 2:
A kind of novel anti high temperature creep diecast magnesium alloy, its alloy ingredient comprises Al 9.0 by ratio of weight and the number of copies, and Zn 0.90, and Nd 0.5, and Mn 0.4 and remainder are made up of Mg and unavoidable impurities.
The proportioning of Mg-Nd alloy is identical with embodiment 1 with the melting mode.
Embodiment 3:
A kind of novel anti high temperature creep diecast magnesium alloy, its alloy ingredient comprises Al 9.0 by ratio of weight and the number of copies, and Zn 0.90, and Y 0.1, and Nd 0.5, and Mn 0.4, and remainder is made up of Mg and unavoidable impurities.
The proportioning of Mg-Nd-Y alloy is identical with embodiment 1 with the melting step.

Claims (6)

1, a kind of novel anti high temperature creep diecast magnesium alloy is characterized in that: the composition of alloy is (by ratio of weight and the number of copies): Al 8.0-9.5, and Zn 0.45-0.90, Y 0.5-3.0, and remainder is made up of Mg and unavoidable impurities.
2, a kind of novel anti high temperature creep diecast magnesium alloy is characterized in that: the composition of alloy is (by ratio of weight and the number of copies): Al 8.0-9.5, and Zn 0.45-0.90, Nd 0.5-3.0, and remainder is made up of Mg and unavoidable impurities.
3, a kind of novel anti high temperature creep diecast magnesium alloy, it is characterized in that: the processing step of alloy is as follows, comprises the preparation and the melting of alloy:
(1) preparation of alloy comprises following two kinds of methods:
Method 1:
The employing raw material is: AZ91HP alloy, pure Al for calculate umber 1.05, Mg-Y (Nd) master alloy is for calculating 1.03 of umber, electrolysis Zn is for calculating 1.03 of umber;
Method 2;
The employing raw material is: magnesium ingot for calculate umber 1.08), pure Al for calculate umber 1.02, electrolysis Zn for calculate umber 1.01, Al-Mn alloy, Mg-Y (Nd) master alloy be for calculating 1.03 of umber.
(2) melting of alloy:
1. the raw material that method 1 is configured adds in the following order: with the AZ91HP alloy, and electrolysis Zn, pure Al after the mixing is warming up to it 685-690 ℃ of fusing, is promptly feeding mixed gas protectedly more than 420 ℃, and its ratio of gas mixture is: N 2+ 0.002-0.005%SF 6, add Mg-Y (Nd) master alloy until completely melted, static 30 minutes, and keep melt temperature at 680-690 ℃, get final product die casting or reduce to 620-630 ℃ of cast alloy cast ingot.
2. the raw material that method 2 is configured removes Mg-Y (Nd) master alloy, all the other raw materials are pressed the general melting program melting of AZ91HP alloy, after treating that alloy is finished refining, keep melt temperature at 690-710 ℃, add Mg-Y (Nd) master alloy, and logical Ar stirred 20 minutes, and is static to 690 ℃ of die casting or reduce to 620-630 ℃, the cast alloy cast ingot.
4, a kind of novel anti high temperature creep diecast magnesium alloy according to claim 1 is characterized in that described Y content is 0.7 by weight.
5, a kind of novel anti high temperature creep diecast magnesium alloy according to claim 2 is characterized in that described Nd content is by weight for being 0.7.
6, according to claim 1,2 described a kind of novel anti high temperature creep diecast magnesium alloys, it is characterized in that in the described alloy, by weight for containing 0.1-0.4Mn.
CNB031270638A 2003-06-06 2003-06-06 High-temp, creeping resistant compression casting magnesium alloy Expired - Lifetime CN100424209C (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100425720C (en) * 2005-03-31 2008-10-15 鸿富锦精密工业(深圳)有限公司 Creep resistant magnesium alloy materials
CN100430503C (en) * 2006-05-17 2008-11-05 中国科学院金属研究所 High-strength AZ91HP magnesium-alloy and its production
CN102296221A (en) * 2011-09-22 2011-12-28 中南大学 High-ductility high-yield-strength magnesium alloy
CN104152826A (en) * 2014-07-17 2014-11-19 南昌大学 Heat treatment method for Mg-Al-Zn-Y rare-earth magnesium alloy
CN107523729A (en) * 2016-06-20 2017-12-29 张家港市华舰五金工具有限公司 Deformable rare earth magnesium alloy and preparation method thereof
CN115652158A (en) * 2022-10-25 2023-01-31 西安交通大学 Creep-resistant Mg-Al wrought magnesium alloy and preparation method thereof

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IL125681A (en) * 1998-08-06 2001-06-14 Dead Sea Magnesium Ltd Magnesium alloy for high temperature applications
JP2002275569A (en) * 2001-03-14 2002-09-25 Ryobi Ltd CREEP RESISTANT Mg ALLOY

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100425720C (en) * 2005-03-31 2008-10-15 鸿富锦精密工业(深圳)有限公司 Creep resistant magnesium alloy materials
CN100430503C (en) * 2006-05-17 2008-11-05 中国科学院金属研究所 High-strength AZ91HP magnesium-alloy and its production
CN102296221A (en) * 2011-09-22 2011-12-28 中南大学 High-ductility high-yield-strength magnesium alloy
CN104152826A (en) * 2014-07-17 2014-11-19 南昌大学 Heat treatment method for Mg-Al-Zn-Y rare-earth magnesium alloy
CN104152826B (en) * 2014-07-17 2016-08-24 南昌大学 A kind of heat treatment method of Mg-Al-Zn-Y magnesium-rare earth
CN107523729A (en) * 2016-06-20 2017-12-29 张家港市华舰五金工具有限公司 Deformable rare earth magnesium alloy and preparation method thereof
CN115652158A (en) * 2022-10-25 2023-01-31 西安交通大学 Creep-resistant Mg-Al wrought magnesium alloy and preparation method thereof
CN115652158B (en) * 2022-10-25 2023-08-11 西安交通大学 Creep-resistant Mg-Al deformed magnesium alloy and preparation method thereof

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