Summary of the invention
In order to solve above-mentioned problems of the prior art, the embodiment of the present invention provides a kind of low-shrinkage magnesium alloy.Described technical scheme is as follows:
A kind of low-shrinkage magnesium alloy, described magnesium alloy is made up of Mg, Al, Mn, rare earth (RE), Nb, Li, its weight percent consists of Al 1.5-25%, Mn 0.13-2%, rare earth 0.0002-16%, Nb 0.0002-4%, Li 0.0002-9%, and all the other are Mg.
Wherein, described rare earth is at least one in Gd, Y, Sc, Sm, Pr, Yb, Nd, La, Ce, Tb, Dy, Ho and Er.
Preferably, described rare earth is at least one in Gd or Gd and Y, Sc, Sm, Pr, Yb, Nd, La, Ce, Tb, Dy, Ho and Er.
Preferably, its weight percent consists of Al 1.6-6.5%, Mn 0.13-0.7%, Gd 0.1-2%, Nb 0.05-1%, Li 0.02-2%, and all the other are Mg.
More have choosing, its weight percent consists of Al 4.4-6.5%, Mn 0.26-0.6%, Gd 0.1-0.8%, Nb 0.05-0.6%, Li 0.02-2%, and all the other are Mg.
Most preferably, its weight percent consists of Al 6%, Mn 0.45%, Gd 0.4%, Nb 0.2%, Li 0.5%, and all the other are Mg.
The beneficial effect that the technical scheme that the embodiment of the present invention provides is brought is: in magnesium alloy provided by the invention, RE can form MgRE compound with Mg, Nb can form some resistant to elevated temperatures metallic compounds with other elements (as Al), and Li has strong crystal grain thinning and purifies aluminium alloy effect.Due to the combined action of above-mentioned element, while making alloy graining, latent heat changes, under the heat absorption of above-mentioned element, heat release combined action, it is diecast magnesium alloy that the time that aluminium alloy provided by the invention keeps liquid in mould is obviously longer than existing AM, make alloy in process of setting, feeding is abundant, built-in thermal stress is little, heat crack resistance is good, simultaneously, because magnesium alloy liquid volume and solid-state volume variation that the embodiment of the present invention provides are very little, therefore there is the feature that cavity filling ability is good, shrinking percentage is low.The characteristics such as alloy of the present invention also has good mechanical property, and machinability, mobility and die casting are good.
Embodiment
For making the object, technical solutions and advantages of the present invention clearer, below embodiment of the present invention is described further in detail.
Manufacture craft, the heat treating method of the magnesium alloy that the embodiment of the present invention provides are described as follows:
1, the magnesium alloy that the embodiment of the present invention provides can be made by following three kinds of melting technologies:
Technique one: the magnesium alloy composition and the content alloyage that provide according to the embodiment of the present invention; in resistance furnace, add magnesium ingot, aluminium ingot, MgMn master alloy, AlNb master alloy or NbAl master alloy; heat up to resistance furnace used, in the time that the above-mentioned metal adding melts soon, adopt argon shield or magnesium alloy covering agent protection.While being warmed up to 720 DEG C-780 DEG C, add MgRE master alloy (as MgGd, MgY, MgNd etc.) or AlRE master alloy, AlLi master alloy or MgLi master alloy, and stir, leave standstill insulation 30 minutes at 720 DEG C-780 DEG C, obtain aluminium alloy.Water a fritter sample with gained aluminium alloy, detect its Melting Quality, as: carry out gas content inspection according to gas content inspection method, if second-rate, need carry out refining treatment; If up-to-standard, described aluminium alloy temperature adjustment to 700 DEG C-740 DEG C is skimmed, then pour into a mould, obtain the foundry goods of alloy of the present invention.
In this technique, resistance furnace also can replace with other smelting furnaces; Magnesium alloy covering agent and master alloy product are market sale product; Refining treatment method adopts the ordinary method of the industry.
Technique two: the magnesium alloy composition and the content alloyage that provide according to the embodiment of the present invention, in vacuum oven, add aluminium ingot, Mn or Mn agent, AlNb master alloy or NbAl master alloy, be warming up to 820 DEG C, insulation 2-8 hour, then cool to 720 DEG C-780 DEG C, add magnesium ingot, RE, AlLi master alloy or MgLi master alloy.After added melting of metal, 720 DEG C-780 DEG C insulations 30 minutes, obtain aluminium alloy, adopt argon shield or magnesium alloy covering agent protection to prevent aluminium alloy oxidation.Water a fritter sample with gained aluminium alloy, detect its Melting Quality, as: the inspection of gas content, if second-rate, need carry out refining treatment; If up-to-standard, described aluminium alloy temperature adjustment to 700 DEG C-740 DEG C is skimmed, then pour into a mould, obtain the foundry goods of alloy of the present invention.
In this technique, vacuum oven can substitute with other smelting furnaces such as main frequency furnaces; Magnesium alloy covering agent, rare earth, Mn agent, master alloy are sell goods on market; Refining treatment method adopts the ordinary method of the industry.
Technique three: the magnesium alloy composition and the content alloyage that provide according to the embodiment of the present invention; in smelting furnace, adding standard brand MgAlMn is diecast magnesium alloy, AlNb master alloy or NbAl master alloy, and above-mentioned metal adopts argon shield or magnesium alloy covering agent protection while fusing soon.While being warmed up to 720 DEG C-780 DEG C, add MgRE master alloy (as MgGd, MgY, MgNd etc.) or AlRE master alloy, AlLi master alloy or MgLi master alloy, and stir, leave standstill insulation 30 minutes at 720 DEG C-780 DEG C, obtain aluminium alloy.Water a fritter sample with gained aluminium alloy, detect its Melting Quality, as: carry out gas content inspection according to gas content inspection method, if second-rate, need carry out refining treatment; If up-to-standard, described aluminium alloy temperature adjustment to 700 DEG C-740 DEG C is skimmed, then pour into a mould, obtain the foundry goods of alloy of the present invention.
In this technique, magnesium alloy covering agent and master alloy are sell goods on market; Refining treatment method adopts the ordinary method of the industry.
Thermal treatment and the treatment process thereof of the magnesium alloy that 2, the embodiment of the present invention provides:
Die casting in the magnesium alloy that the embodiment of the present invention provides can not heat-treated, and the cast member of other form can be heat-treated, and generally adopts T4 solution treatment.T4 solid solution treatment process is: cast member is warming up in chamber type electric resistance furnace to 390 DEG C, argon shield, is incubated 16 hours, cast member come out of the stove after shrend, 50 DEG C of water temperatures.
Be subject to fusion process to select the impact of some other inevitable factor in the purity of raw material and melting, castingprocesses, the diecast magnesium alloy that the embodiment of the present invention provides may contain inevitable impurity, as Zn, Fe, Cu, Be etc., as long as described impurity does not cause obvious impact to the performance of magnesium alloy, and total impurities is controlled at the weight percent < 0.5% in described magnesium alloy finished product, in the weight percent < 0.1% of single contaminant in described magnesium alloy finished product, exist trace impurity also to allow.
Embodiment 1
Prepare magnesium alloy by step described in above-mentioned technique one, foundry goods adopts die cast, and the weight percent of described magnesium alloy consists of Al 1.5%, Mn 0.13%, Sm 0.0002%, Nb 0.0002%, Li 0.0002%, and all the other are Mg.
Foundry goods is heat-treated.The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Embodiment 2
Prepare magnesium alloy by step described in above-mentioned technique one, foundry goods adopts semi-solid casting, and the weight percent of described magnesium alloy consists of Al 25%, Mn 2%, Y 16%, Nb 4%, Li 9%, and all the other are Mg.
Foundry goods is heat-treated.The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Embodiment 3
Prepare magnesium alloy by step described in above-mentioned technique two, foundry goods adopts Hpdc, and the weight percent of magnesium alloy consists of Al 6%, Mn 0.2%, Gd 0.2%, Nb 1%, Li 0.6%, and all the other are Mg;
The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Embodiment 4
Prepare magnesium alloy by step described in above-mentioned technique one, foundry goods adopts low-pressure casting, and the weight percent of described magnesium alloy consists of Al 1.6%, Mn 0.13%, Ho 0.1%, Nb 0.05%, Li 0.02%, and all the other are Mg.
Foundry goods is heat-treated.The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Embodiment 5
Prepare magnesium alloy by step described in above-mentioned technique three, described standard brand diecast magnesium alloy used in preparation process is AM60B, foundry goods adopts precision casting, and the weight percent of described magnesium alloy consists of Al 6.5%, Mn 0.7%, Gd 2%, Nb 1%, Li 2%, and all the other are Mg.
Foundry goods is heat-treated.The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Embodiment 6
Prepare magnesium alloy by step described in above-mentioned technique one, foundry goods adopts sand mold casting, and the weight percent of described magnesium alloy consists of Al 4.4%, Mn 0.26%, Gd 0.1%, Nb 0.05%, Li 0.02%, and all the other are Mg.
Foundry goods is heat-treated.The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Embodiment 7
Prepare magnesium alloy by step described in above-mentioned technique two, foundry goods adopts Hpdc, and the weight percent of described magnesium alloy consists of Al 6.5%, Mn 0.6%, Gd 0.8%, Nb 0.6%, Li 2%, and all the other are Mg.
The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Embodiment 8
Prepare magnesium alloy by step described in above-mentioned technique two, foundry goods adopts Hpdc, and the weight percent of described magnesium alloy consists of Al 6.5%, Mn 0.6%, Gd 0.4%, Nd 0.4%, Nb 0.6%, Li 2%, and all the other are Mg.
The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Embodiment 9
Prepare magnesium alloy by step described in above-mentioned technique two, foundry goods adopts Hpdc, and the weight percent of described magnesium alloy consists of Al 6.5%, Mn 0.6%, Ce 0.8%, Nb 0.6%, Li 2%, and all the other are Mg.
The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Embodiment 10
Prepare magnesium alloy by step described in above-mentioned technique two, foundry goods adopts die cast, and the weight percent of described magnesium alloy consists of Al 2%, Mn 0.2%, La 1.2%, Nb 0.8%, Li 0.1%, and all the other are Mg.
Foundry goods is heat-treated.The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Embodiment 11
Prepare magnesium alloy by step described in above-mentioned technique one, foundry goods adopts sand mold casting, and the weight percent of described magnesium alloy consists of Al 6%, Mn 0.5%, Tb 0.6%, Nb 0.4%, Li 0.5%, and all the other are Mg.
Foundry goods is heat-treated.The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Embodiment 12
Prepare magnesium alloy by step described in above-mentioned technique two, foundry goods adopts die cast, and the weight percent of described magnesium alloy consists of Al 10%, Mn 1%, Dy 8%, Nb 2%, Li 1.5%, and all the other are Mg.
Foundry goods is heat-treated.The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Embodiment 13
Prepare magnesium alloy by step described in above-mentioned technique two, foundry goods adopts die cast, and the weight percent of described magnesium alloy consists of Al 3%, Mn 0.65%, Er 1%, Nb 0.7%, Li 0.8%, and all the other are Mg.
Foundry goods is heat-treated.The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Embodiment 14
Prepare magnesium alloy by step described in above-mentioned technique two, foundry goods adopts die cast, and the weight percent of described magnesium alloy consists of Al 5%, Mn 0.5%, Sc 0.5%, Nb 0.8%, Li 0.4%, and all the other are Mg.
Foundry goods is heat-treated.The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Embodiment 15
Prepare magnesium alloy by step described in above-mentioned technique one, foundry goods adopts Hpdc, and described magnesium alloy weight percent consists of Al6%, Mn 0.45%, Gd 0.4%, Nb 0.2%, Li 0.5%, and all the other are Mg.
The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Comparative example 1
Prepare magnesium alloy by step described in above-mentioned technique one, foundry goods adopts Hpdc, and described magnesium alloy weight percent consists of Al6%, Mn 0.45%, Gd 0.4%, Nb 0.2%, and all the other are Mg and inevitable impurity.
The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Comparative example 2
Prepare magnesium alloy by step described in above-mentioned technique one, foundry goods adopts Hpdc, and described magnesium alloy weight percent consists of Al6%, Mn 0.45%, Gd 0.4%, Li 0.5%, and all the other are Mg and inevitable impurity.
The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
Comparative example 3
Prepare magnesium alloy by step described in above-mentioned technique one, foundry goods adopts Hpdc, and described magnesium alloy weight percent consists of Al6%, Mn 0.45%, Gd 0.4%, and all the other are Mg and inevitable impurity.
The performance of the Mg alloy castings that the present embodiment provides is referring to table 1.
The Mg alloy castings that each embodiment provides above can contain micro-impurity, the weight percent < 0.5% of described inevitable total impurities in described magnesium alloy finished product, the weight percent < 0.1% of single contaminant in described magnesium alloy finished product.
The linear shrinkage ratio of the Mg alloy castings that various embodiments of the present invention and comparative example provide is referring to table 1.
The linear shrinkage ratio table of the Mg alloy castings that the each embodiment of table 1 provides
As shown in Table 1, the linear shrinkage ratio of the Mg alloy castings that the embodiment of the present invention provides is all less than 1%, is diecast magnesium alloy well below existing MgAlMn, has good hot-cracking resistance; Simultaneously referring to embodiment 15 and comparative example 1-3, the Mg alloy castings that the embodiment of the present invention provides, compared with not adding Li or Nb or Mg alloy castings that both all do not add, has better hot-cracking resistance; The linear shrinkage ratio of embodiment 7,8 and 15 is lower than other embodiment, and the scope of embodiment 7,8 and 15 each components is in Al4.4-6.5%, Mn 0.26-0.6%, Gd 0.1-0.8%, Nb 0.05-0.6%, Li 0.02-2%; By the contrast between embodiment 7-9, the known RE containing has the effect of Gd better; The linear shrinkage ratio of the Mg alloy castings that embodiment 15 provides is minimum, and the cast magnesium alloys hot-cracking resistance that embodiment 15 provides is the strongest.
The foregoing is only preferred embodiment of the present invention, in order to limit the present invention, within the spirit and principles in the present invention not all, any amendment of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.