CN101245430A - High-fire resistance A1-Cu-Mg-Ag alloy - Google Patents

Abstract

The invention discloses an Al-Cu-Mg-Ag alloy with high heat resistance, the components of which by weight percentage are: 4.6-6.6 percent of Cu, 0.4-0.65 percent of Mg, 1-1.5 percent of Ag, 0-0.06 percent of Fe, 0-0.06 percent of Si, 0.25-0.35 percent of Mn, 0.1-0.2 percent of Zr and the rest is Al. In the invention, the content of Ag in the Al-Cu-Mg-Ag alloy is increased and the atomic ratio of the Ag/Mg is properly increased, which results in that the alloy matrix has more Ohm phase nucleation sites and the Al-Cu-Mg-Ag alloy has more Ohm phases under high temperature, the alloy matrix obtains large amount of dispersed and fine strengthening phases to ensure that the Al-Cu-Mg-Ag alloy has excellent high-temperature short-time tensile property, high temperature stress rupture property, and good structure property and stability after long term thermal exposure; furthermore, the room temperature mechanical properties of the Al-Cu-Mg-Ag alloy of the invention is also superior to that of the existing Al-Cu-Mg-Ag alloy.

Description

A kind of high-fire resistance A 1-Cu-Mg-Ag alloy

Technical field

The present invention relates to a kind of Al-Cu-Mg-Ag alloy, particularly have the Al-Cu-Mg-Ag alloy of high heat resistance.

Background technology

In recent years, Al-Cu-Mg-Ag to high Cu/Mg ratio is that alloy is studied both at home and abroad, finding that this alloy has good thermostability, solidity to corrosion, fracture toughness property, traumatic resistance energy and moulding processability, is heat resistance, the damnification resistant aluminum alloy that promises to be the aircraft skin material most.Under certain alloying element content and thermal treatment process condition, can separate out a kind of new enhanced phase-Ω phase in the Al-Cu-Mg-Ag refractory alloy, this heat-resisting phase can be 200 ℃ of following steady in a long-term existence and not alligatoring and gathering are grown up, and make this alloy become possibility at 200 ℃ of long services down even more than 200 ℃.In the Al-Cu-Mg ternary alloy, Mg and Cu form the Mg-Cu elementide, make the Mg atomic quantity reduce, thereby obviously reduce the nucleation site of Ω phase; And in the Al-Cu-Mg-Ag alloy, add after the Ag element, because Ag atom and Mg atomic reaction are quite strong,, be beneficial to the forming core of Ω phase so Ag captures the Mg atom and forms the Ag-Mg elementide.Therefore control Mg, the Ag constituent content that Al-Cu-Mg-Ag is an alloy, obtain suitable Ag/Mg atomic ratio, will help the tiny Ω phase of diffusion-precipitation.Existing Al-Cu-Mg-Ag is that the Ag content of alloy mostly is 0.5%wt greatly, and long-time lasting or creep meeting makes its heat-resisting phase-Ω assemble alligatoring gradually mutually in temperature more than 200 ℃, and then the thermostability of alloy is descended.Trace it to its cause, may be because Ag/Mg atomic ratio mismatch, cause the Ag-Mg elementide in the alloy substrate at high temperature to be broken up gradually, make the nucleation site of Ω phase reduce because of atomic diffusion, and original Ω alligatoring gradually mutually, so the total number of Ω phase and density decline in the alloy.Therefore, how controlling each content of elements and ratio in this alloy, make its long-time heat in the time of 150 ℃-275 ℃ expose or lose efficacy lastingly and not, is that raising Al-Cu-Mg-Ag is the problem of the solution of needing badly in the hot Study on Structure Property of alloy.

Summary of the invention

Technical problem to be solved by this invention is that suitably to adjust Al-Cu-Mg-Ag be each content of elements and ratio in the alloy, making Al-Cu-Mg-Ag is that alloy at high temperature has more Ω phase, make alloy substrate obtain the enhanced tissue of small and dispersed, thus the structure property after the room-temperature mechanical property, high temperature endurance performance, high-temperature short delay stretching performance and the good long-time heat that make alloy have excellence expose.

For achieving the above object, the contriver proposes a kind of Al-Cu-Mg-Ag alloy, the mass percentage content of this each element of alloy is: Cu 4.6～6.6%, Mg 0.4～0.65%, and Ag 1～1.5%, and Fe 0～0.06%, Si 0～0.06%, Mn 0.25～0.35%, and Zr 0.1～0.2%, and surplus is Al.

In the present invention, the mass percentage content of Ag is preferably 1.3～1.5%, and the Ag/Mg atomic ratio is preferably about 0.5～1.

With existing Al-Cu-Mg-Ag alloy phase ratio, the present invention improves Ag content in the alloy, and suitably improve the Ag/Mg atomic ratio, can make like this and have more Ω phase nucleation site in the alloy substrate, make alloy at high temperature have more Ω phase, obtain the tiny strengthening phase of a large amount of disperses in the alloy substrate, structure property, stability after thereby the high-temperature short delay stretching performance, high temperature endurance performance and the good long-time heat that make alloy have excellence expose, and the alloy at room temperature mechanical property also is better than existing Al-Cu-Mg-Ag alloy.

Show by experiment: under the identical heat-treat condition, it is about 0.5% Al-Cu-Mg-Ag alloy that alloy of the present invention all is better than Ag content through the tensile strength behind the high-temperature short delay stretching, yield strength, be much better than 2024 grades commonly used 2 * * * line aluminium alloy; It is about 0.5% Al-Cu-Mg-Ag alloy that tensile strength, the yield strength of alloy of the present invention after different temperature and time heat exposes all is better than Ag content; It is about 0.5% Al-Cu-Mg-Ag alloy that alloy of the present invention is better than Ag content through the time of different temperature and load high-temperature and durable, is about 0.5% Al-Cu-Mg-Ag alloy but its elongation after fracture is lower than Ag content; It is about 0.5% Al-Cu-Mg-Ag alloy that alloy at room temperature tensile strength of the present invention, yield strength all are better than Ag content.

Description of drawings

Fig. 1 is 1# alloy and 2# alloy in the high-temperature short delay stretching performance map of 150 ℃, 200 ℃, 250 ℃ and 275 ℃;

Fig. 2 is 1# alloy and the residue room-temperature mechanical property figure of 2# alloy after 200 ℃ of long-time heat expose;

Fig. 3 is 1# alloy and the room-temperature mechanical property figure of 2# alloy after 250 ℃ of timeliness;

Fig. 4 is 3# alloy and the room-temperature mechanical property figure of 4# alloy after 200 ℃ of timeliness;

Fig. 5 (a) and Fig. 5 (b) are respectively 1# alloy and the intracrystalline TEM photo of 2# alloy behind 250 ℃ of timeliness 0.5h.

Embodiment

The concrete composition of each alloy and numbering are as shown in table 1 among the embodiment, and wherein 1# and 3# are embodiments of the invention, and 2# and 4# are Comparative Examples.

Embodiment 1:

Press each alloying element of table 1 proportioning, be equipped with 1# and 2# alloy cast ingot, be rolled into light sheet through the melting and casting legal system, in 515 ℃ of solid solutions 6 hours and shrend, then 165 ℃ of timeliness 2 hours, the oil bath slow cooling.Two kinds of alloys are carried out high-temperature short delay stretching in 150 ℃, 200 ℃, 250 ℃ and 275 ℃ insulation after 15 minutes respectively.After 150 ℃ of stretchings, the 1# tensile strength of alloys is 390MPa, and the 2# tensile strength of alloys is 325MPa.Two kinds of alloys tensile strength after 200 ℃, 200 ℃, 250 ℃ and 275 ℃ of stretchings, yield strength and unit elongation are as shown in Figure 1.Data show: under identical heat-treat condition, the high-temperature short delay stretching performance of high Ag alloy is better than low Ag alloy, this is because the Ag in the high Ag alloy provides the position for the forming core of Ω strengthening phase, in the high-temperature short delay stretching process, the gathering coarsening rate of Ω strengthening phase is not obvious, thereby advantages of higher tensile strength and yield strength are still arranged.

Embodiment 2:

Press each alloying element of table 1 proportioning, be equipped with 1# and 2# alloy cast ingot, be rolled into light sheet, in 515 ℃ of solid solutions 6 hours and shrend, then 165 ℃ of timeliness 2 hours through the melting and casting legal system.Carry out the high-temperature and durable experiment at 200 ℃ respectively through two kinds of alloys after this processing.Experimental result is: the 1# alloy is at 200 ℃, and 100 hours stress-rupture strength limit is 240Mpa, promptly ${\mathrm{\σ}}_{100}^{200}=240\mathrm{Mpa};$ The 2# alloy is at 200 ℃, and 100 hours stress-rupture strength limit is 220Mpa, promptly ${\mathrm{\σ}}_{100}^{200}=220\mathrm{Mpa}.$ Data show: under identical heat-treat condition, the high temperature endurance performance of high Ag alloy is better than low Ag alloy.

Embodiment 3:

Press each alloying element of table 1 proportioning, be equipped with 1# and 2# alloy cast ingot, be rolled into light sheet, in 515 ℃ of solid solutions 6 hours and shrend, then 165 ℃ of timeliness 2 hours through the melting and casting legal system.Two kinds of alloys through this processing carry out heat exposure experiment at 200 ℃ respectively, and heat exposure time was followed successively by 10 hours, and 20 hours, 50 hours, 80 hours and 100 hours.After heat exposes and finishes, sample is carried out the room temperature mechanics stretch.Experimental result is: the 1# alloy is through 10 hours, and 20 hours, 50 hours, tensile strength after 80 hours and 100 hours heat exposes is followed successively by 469.16MPa, 453.16MPa, 449.08MPa, 431.22MPa and 425.24MPa, yield strength is followed successively by 450.37MPa, 442.44MPa, 435.06MPa, 410.55MPa and 391.25MPa, unit elongation is followed successively by 5.92%, 6.04%, 5.96%, 6.54% and 6.32%; The 2# alloy is through 10 hours, and 20 hours, 50 hours, tensile strength after 80 hours and 100 hours heat exposes is followed successively by 432.89MPa, 425.05MPa, 423.54MPa, 379.68MPa and 348.15MPa, yield strength is followed successively by 412.90MPa, 403.65MPa, 403.60MPa, 352.69MPa and 321.62MPa, unit elongation is followed successively by 6.64%, 6.52%, 7.48%, 7.32% and 6.58%.Specifically as shown in Figure 2.Data show: under identical heat-treat condition, the tensile strength of high Ag alloy after heat exposes certain hour all is higher than the low Ag alloy that heat exposes the identical time with yield strength.

Embodiment 4:

Press each alloying element of table 1 proportioning, be equipped with 1# and 2# alloy cast ingot, be rolled into light sheet, in 515 ℃ of solid solutions 6 hours and shrend through the melting and casting legal system, 250 ℃ of timeliness, aging time point is chosen 5 minutes successively then, and 10 minutes, 30 minutes, 1 hour, 2 hours, 4 hours.

At room temperature carry out the mechanics stretching experiment respectively through two kinds of alloys after the above-mentioned processing.Experimental result is: the 1# alloy reaches the peak timeliness in timeliness after about 10 minutes, and its peak timeliness tensile strength is 498.68MPa, and yield strength is 470.36MPa, and unit elongation is 9.94%; The peak timeliness tensile strength of 2# alloy is 475MPa, and yield strength is 442.55MPa, and unit elongation is 12.32%, specifically as shown in Figure 3.

Two kinds of alloys at the transmission electron microscope photo of 250 ℃ of timeliness after 30 minutes as shown in Figure 5, as seen from the figure: the strengthening phase Ω in the TEM photo during 250 ℃ of timeliness 0.5h of 1# alloy is small and dispersed relatively, density is big, and alligatoring is also not serious, and a little θ ' phase (Al is arranged on the matrix ₂Cu) separate out, tiny Ω also helps hindering dislocation motion mutually, improves strength of alloy.And for the 2# alloy, the Ω phase coarsening rate in the matrix is relatively large, and a little θ ' phase (Al is also arranged on the matrix ₂Cu) separate out.Experimental result shows: under identical heat-treat condition, high Ag alloy at room temperature mechanical property is better than low Ag alloy.

Embodiment 5:

Press each alloying element of table 1 proportioning, be equipped with 1# and 2# alloy cast ingot, be rolled into light sheet, in 515 ℃ of solid solutions 6 hours and shrend, then 200 ℃ of timeliness 2 hours through the melting and casting legal system.Carry out the high-temperature and durable experiment at 250 ℃ respectively through two kinds of alloys after this processing.Experimental result is: the 3# alloy is at 250 ℃, and 100 hours stress-rupture strength limit is 140Mpa, promptly ${\mathrm{\σ}}_{100}^{250}=140\mathrm{Mpa};$ The 4# alloy is at 250 ℃, and 50 hours stress-rupture strength limit is 140Mpa, promptly ${\mathrm{\σ}}_{50}^{250}=140\mathrm{Mpa}.$ Data show: under identical heat-treat condition, the high temperature endurance performance of high Ag alloy is better than low Ag alloy.

Embodiment 6:

Press each alloying element of table 1 proportioning, be equipped with 1# and 2# alloy cast ingot, be rolled into light sheet through the melting and casting legal system, in 515 ℃ of solid solutions 6 hours and shrend, 200 ℃ of timeliness, aging time point is chosen 5 minutes successively then, 10 minutes, 30 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours and 12 hours.At room temperature carry out the mechanics stretching experiment respectively through two kinds of alloys after this processing.Experimental result is: the 3# alloy reaches the peak timeliness in timeliness after about 1 hour, and its peak timeliness tensile strength is 535.84MPa, and yield strength is 517.15MPa, and unit elongation is 7.68%; The peak timeliness tensile strength of 4# alloy is 522.86MPa, and yield strength is 505.55MPa, and unit elongation is 7.28%.Specifically as shown in Figure 4.Data show: under identical heat-treat condition, high Ag alloy at room temperature mechanical property is better than low Ag alloy.

Claims (2)

1. high-fire resistance A 1-Cu-Mg-Ag alloy, it is characterized in that: the mass percentage content of each element is in the described alloy: Cu 4.6～6.6%, Mg 0.4～0.65%, Ag 1～1.5%, Fe 0～0.06%, and Si 0～0.06%, and Mn 0.25～0.35%, Zr 0.1～0.2%, and surplus is Al.

2. alloy as claimed in claim 1 is characterized in that: the mass percentage content of Ag is 1.3～1.5% in the described alloy, and the Ag/Mg atomic ratio is 0.5～1.

Images