CN1096059A

CN1096059A - High-strength and high-compactness casted aluminium-silicon alloy

Info

Publication number: CN1096059A
Application number: CN 93106415
Authority: CN
Inventors: 王秉玉; 舒秋阳; 王永正; 章捷; 张风娥
Original assignee: No211 Factory
Current assignee: No211 Factory
Priority date: 1993-06-03
Filing date: 1993-06-03
Publication date: 1994-12-07
Anticipated expiration: 2013-06-03
Also published as: CN1032872C

Abstract

A kind of poisonous alloying element (as beryllium etc.) that do not contain, the high strength, the high-compactness casted aluminium-silicon alloy that use the general industry pure raw materials to produce, its chemical ingredients is: Si7-10%, Mg0.15-0.3%, Cu1.75-2.5%, Mn0.2-0.35%, RE0.01-0.04%, B, Ti trace, major impurity Fe≤0.3%, wherein RE does not use as alterant, only as additive, to improve the elongation of alloy.Of the present inventionly found that cost is low, technology is simple and easy to do, replace alloys such as ZL101A, ZL114A and can obtain very high economic benefit.

Description

High-strength and high-compactness casted aluminium-silicon alloy

The present invention relates to a kind of casting Alar, particularly a kind of high-strength and high-compactness casted aluminium-silicon alloy.

As everyone knows, casting Alar commonly used at present, though as ZL104, ZL101 etc. good castability and high density are arranged, its mechanical property, particularly elongation are low, can not adapt to growing high-tech needs.

Current external, obtaining remarkable progress aspect high strength, the high-compactness casted aluminium-silicon alloy, and be used for producing.Several representational alloys are listed in table 1:

Table 1

S ^*-sand mold casting

The J-permanent mold casting

T ₆-solution treatment adds the total man and imitates man-hour

T ₅-solution treatment adds incomplete artificial aging

The characteristics of these alloys are: high density and high mechanical property are arranged.At J, T ₆Under the state, σ _bAll greater than 294MPa; δ ₅Also can be greater than 3%; At S, T ₆Under the state, σ _bThough can reach the level of 294MPa basically, δ ₅Still lower, only be in 〉=2%.Why the mechanical property of these alloys can reach present level, major cause has been to use highly purified material, alloy impurity iron (Fe) content is controlled at below 0.2%, or has added the bigger alloying element beryllium (Be) of toxicity in alloy, or the two has it concurrently.

At present, domesticly also obtained bigger progress at alloy research of the same type and application facet, several representational alloys are listed in table 2.

Table 2

B ^*-rotten the processing

The approach that the listed alloy mechanical performance of table 2 improves also has been to use highly purified starting material or has used Be, as ZL101A, ZL114A, ZL116A etc.; Though what have does not use highly purified starting material or Be, as T84, let it be to the greatest extent σ _bHigher, but δ ₅Too low, still less than 1%, therefore still can not satisfy the demand.

The object of the present invention is to provide and a kind ofly neither use highly purified starting material to found, do not add the high-strength and high-compactness casted aluminium-silicon alloy of the big alloying element beryllium of toxicity again.

The present invention can realize by following measure:

The composition and the content range thereof of alloy of the present invention are as follows: Cu1.75-2.5%, Si7-10%, Mg0.15-0.3%, Mn0.2-0.35%, cerium-rich mischmetal RE0.01-0.04%, B, Ti trace, major impurity Fe≤0.3%, Al are surplus.Because the silicon content of this alloy is higher, has advantages of good casting and high density admittedly can guarantee it; Cu and Mg all participate in ageing strengthening, and comparable Cu or Mg participate in ageing strengthening separately and obtain better strengthening effect, so this alloy has higher tensile strength.

By table 2 as seen, although also added manganese among the T85, T84 alloy, with the harmful effect that reduces impurity F e (with the Tens-50 alloy phase than), the elongation of alloy is still very low, its reason is conspicuous, promptly the effect of manganese is far away from beryllium.In view of above-mentioned this reason, the present invention then wards off new technology approach in addition, by a large amount of tests, uses cerium-rich mischmetal metal replacement beryllium and has obtained success.

Current both at home and abroad all with the alterant use of cerium-rich mischmetal metal as cast Al-Si alloy, its consumption (is accounting for alloy liquid gross weight) more than 0.2%.The present invention is then different, and it as a kind of additive, is improved the elongation of alloy, so consumption is extremely low.Result of study shows the variation with RE content in the alloy, and tensile strength of alloys changes little, but δ ₅Alter a great deal.Originally the increase of measuring with RE, δ ₅Increase, when RE content reaches 0.025% left and right sides, δ ₅Reach maximum, after this if continue to increase RE content, δ ₅Just descend fast.As seen an amount of RE is different with Mg, Cu etc. to the influence of alloy mechanical performance, and its advantage is, does not lose σ basically _bThe time can make the δ of former alloy ₅Improve about 30%.

Alloy melting carries out in electrical crucible, and alloy is founded top temperature≤760 ℃ of process interalloy liquid, and alloy carries out degassing processing at 740-750 ℃, and degasifier is C ₂Cl ₆Consumption is 0.4% of an alloy liquid total amount; After alloy leaves standstill 5-10 minute after the degasification, carry out inoculation, add the aluminium rare earth intermediate alloy then, adding temperature is 740-750 ℃, the processing of going bad at last, and alterant is the mixture of NaCl, NaF, KCl, consumption is the 1.4-1.5% of alloy liquid weight.Master alloys such as Al-Mn, Al-Cu, Al-Si add with aluminium ingot together with remelting.Remelting adds before the degasification of alloy liquid with magnesium ingot, and adding temperature is 720 ℃.

This heat treatment of alloy technology is carried out in the air cycle electric furnace, and the process of thermal treatment parameter sees Table 3.

Table 3

Alloy of the present invention meets design and production requirement, has good performance, compares with domestic and international high-strength casting Alar to reach international standards, and has following advantage:

Because it is higher among the present invention to the permission content of the very harmful impurity iron of alloy mechanical performance, can reach 0.3%, do not contain deleterious alloying element Be etc. again, therefore the present invention can use the pure starting material of general industry to found, so can reduce cost of alloy greatly, melting equipment need not to undergo technological transformation, and can save environmental protection investments; Alloying element content wide ranges in addition, alloying constituent are easy to guarantee that melting technology is simple and easy to do.Multiple user mode is arranged, easily satisfy the service requirements of different user.Just because of this, conventional cast aluminium alloys such as cost of the present invention and ZL104 are close, but mechanical property has reached the level of the aluminum silicon alloy of rafifinal production.

Enumerate 4 specific embodiments below:

Embodiment 1:

Alloy melting carries out in the 30Kg electrical crucible, and raw material ratio is as follows:

Alloying constituent

Mg

Mn

Si

Cu

RE

Fe

Al

Content

0.3

0.25

8

2.2

0.03

≤0.3

Content

The used metallic substance of this alloy of melting is as follows: remelting aluminium ingot, remelting magnesium ingot, Al-Mn10% master alloy, Al-Cu50% master alloy, Al-RE10% master alloy, Al-Si14% master alloy, the content of Ce is more than 45% among the RE.

Melting technology is as follows:

717 ℃ add magnesium

742 ℃ of degasification, degasifier C ₂Cl ₆〉=50%

742 ℃ of inoculation, nucleating agent Ti/B=5

740 ℃ add RE

740 ℃ of rotten processing, alterant is that ternary: NaCl40%, NaF45%, KCl15% teeming temperature are 690 ℃, melting total time is no more than 6 hours.

The finished product composition sees the following form:

Si	Cu	Mg	Mn	Ti	B	RE	Fe (impurity)
								0.92	2.30	0.19	0.27	0.0091	0.0017	0.025	0.26

Mechanical property and heat treatment parameter see the following form:

Embodiment 2

Melting equipment and proportioning raw materials are with embodiment 1, and melting technology is as follows:

716 ℃ add magnesium

740 ℃ of degasification, inoculation, add RE

738 ℃ of rotten processing

690 ℃ of pouring temperatures

The finished product composition sees the following form:

Si	Cu	Mg	Mn	Ti	B	RE	Fe (impurity)
								7.64	2.11	0.20	0.27	0.0064		0.024	0.24

Mechanical property and heat treatment parameter see the following form:

Embodiment 3

Melting equipment and proportioning raw materials are the same, and melting technology is as follows:

720 ℃ add magnesium

740 ℃ of degasification, inoculation

737 ℃ add RE

740 ℃ of rotten processing

690 ℃ of pouring temperatures

The finished product composition sees the following form:

Si	Cu	Mg	Mn	Ti	B	RE	Fe (impurity)
								0.07	1.99	0.10	0.29	0.009		0.023	0.30

Mechanical property and heat treatment parameter see the following form:

Embodiment 4

725 ℃ add magnesium

740 ℃ of degasification, inoculation

735 ℃ add RE

730 ℃ begin casting, 690 ℃-700 ℃ of pouring temperatures

The finished product composition sees the following form:

Si	Cu	Mg	Mn	Ti	B	RE	Fe (impurity)
								0.24	2.18	0.22	0.28	0.051	0.0016	0.022	0.30

Mechanical property and heat treatment parameter see the following form:

Claims

A kind of high strength, high-compactness casted aluminium-silicon alloy, its chemical ingredients is: Si7-10%, Mg0.15-0.3%, Cu1.75-2.5%, Mn0.2-0.35%, cerium-rich mischmetal (RE) 0.01%-0.04%, B, Ti trace, major impurity Fe≤0.3%.