CN1294285C - Scandium-base large amorphous alloy and method for preparing same - Google Patents

Abstract

The present invention discloses scandium base large uncrystallized alloy which uses scandium as a main component, and rare earth is used as one of basic alloy elements. The form of the present invention can be denoted by the following formula that is Sc60-xCo20 (Y, Gd) 20 Alx or Sc56-yCo20 (Y, Gd) 10+yAl24 or Sc45-zCo10+z (Y, Gd) 20 Al25, wherein x=14 to 25, y=5 to 10, and z=5 to 10. The present invention has the advantages that the critical cooling rate of the scandium base large uncrystallized alloy is low, the present invention has a high specific modulus and heat stability, and the scandium base large uncrystallized alloy is suitable for industrial uses, can be sufficiently heated above glass transition temperature to be processed under a condition that crystallization does not occur, and has high manufacture performance. The rare earth alloy element has the advantages of low purity requirements, simple preparation technology and easy operation.

Description

Scandium-base large amorphous alloy and preparation method thereof

Technical field

The present invention relates to non-crystaline amorphous metal or metallic glass field, specifically relating to a kind of is main component with the scandium, has added an amount of transition element and yttrium rare earth element, and comprises the high ratio modulus scandium-base large amorphous alloy of 50% above volume percent amorphous phase.

Background technology

Since people such as H.S.Chen, A.Inoue, W.L.Johnson prepare multiple bulk amorphous alloys is as Pd-Cu-Si, La-Al-(Ni, Cu)-Co, Mg-(Cu, Ni)-(Y, Nd), since Zr-Al-Ni-Cu, the Zr-Ti-Cu-Ni-Be, bulk amorphous material is because its unique physicals and mechanical property have caused physicist and material scholars' very big concern.At present, the glass transition of bulk amorphous material, glass forming ability or mechanism, crystallization Mechanism, deformation mechanism etc. have become the research focus in Materials science and engineering field.Zr base alloy system is as one of alloy system with the strongest glass forming ability, and its intensity can reach more than the 2000MPa, surpasses the highest steel of present intensity, and specific tenacity and specific rigidity are then considerably beyond steel.Zirconium base massive non-crystalline material specific rigidity reaches 15N.m, is one of the highest material of present specific rigidity.

Summary of the invention

The invention provides novel scandium base (ScAlCo) bulk amorphous alloys of a kind of more high specific stiffness and preparation method thereof, this be the specific rigidity of amorphous alloy material more up to 20N.m, system improves about 33% than the Zr base noncrystal alloy.

The objective of the invention is to realize by the following technical solutions:

Scandium-base large amorphous alloy provided by the invention is to be main component with the scandium, and rare earth is as alloying element, and its atomic ratio is formed and used following formulate:

Sc _60-xCo ₂₀(Y，Gd) ₂₀Al _x

Or Sc _45-zCo _10+z(Y, Gd) ₂₀Al ₂₅

Or Sc ₄₆Co ₂₀Y ₁₀Al ₂₄Or Sc ₄₁Co ₂₀Y ₁₅Al ₂₄

X=14～25 wherein, z=5～10, described each component purity is not less than 90at%, and described scandium-base large amorphous alloy comprises at least 50% volume percent amorphous phase.

The invention provides a kind of preparation method of above-mentioned scandium-base large amorphous alloy, comprise the steps:

1) in the electric arc furnace of the argon atmospher that titanium adsorbs, it is even by needed atom proportioning above-mentioned component to be mixed the back melting;

2) use conventional permanent mold casting method, water and cast from the metal pattern, obtain scandium-base large amorphous alloy Sc _60-xCo _20-y(Y, Gd) _20-zAl _x(x=14～24, y=5～15, z=5～15).

Further, the metal pattern that is adopted can be anhydrous cold or water-cooled metal mould.

Scandium-base large amorphous alloy provided by the invention is compared with existing non-crystaline amorphous metal, and its advantage is:

1, the critical cooling rate of this scandium-base large amorphous alloy is low.Rate of cooling (Rc) can reach the order of magnitude of 100K/s, and it is strong to suppress crystallizing power, is easy to form large-sized non-crystaline amorphous metal, and its size is not less than 1 millimeter in each dimension, and the critical diameter size is not less than 3 millimeters.

2, has high specific modulus.Glassy alloy density is 4.2g/cm ³About, specific modulus is 20N.m, surpass most of crystalline materials and zirconium-base amorphous material (being about 15N.m) as Vit1, and the latter is considered to one of the highest material of specific modulus and specific tenacity usually, the specific Young's modulus of this base amorphous material far surpasses zirconium-base amorphous alloy, and keep quite high limit recoverable strain, demonstrating this is that alloy has excellent elastic performance.

3. high thermostability.Second-order transition temperature surpasses other rare earth based bulk amorphous material and most of Zr base massive non-crystalline material up to 630-670K, has wide supercooling liquid phase region width, and Tx is 98K.

4, this scandium-base large amorphous alloy is suitable for industrial use, can fully be heated to more than the glass transformation temperature and process under the situation that crystallization does not take place.

5, this scandium-base large amorphous alloy has high manufacturing property.The purity requirement of rare earth alloy element is not high, and preparation technology is simple, easy handling.

Description of drawings

The X-ray diffraction analysis spectrum and the selected diffraction style of the non-crystaline amorphous metal of Fig. 1 embodiment 1 (3mm diameter pole).

The DSC graphic representation of Fig. 2 non-crystaline amorphous metal provided by the invention.

Fig. 3 Sc ₃₆Co ₂₀Al ₂₄Y ₂₀The DTA graphic representation.

The relation of Fig. 4 ScAlCo base amorphous material elastic performance and other rare earth based bulk amorphous material and second-order transition temperature.

The comparison of Fig. 5 Sc base amorphous material limit recoverable strain and other non-crystalline material.

Embodiment:

Embodiment 1

Sc ₃₆Co ₂₀Al ₂₄Y ₂₀The preparation of column bulk amorphous alloys

Use purity as more than the 90at.%, atomic ratio is 36: 20: 24: 20 Sc, Co, Al and Y prepare scandium-base large amorphous alloy.At first, mix, obtain alloy cast ingot after the cooling they meltings in the electric arc furnace of the argon atmospher of titanium absorption; Melt back 5-10 minute again, until ingot casting fusing evenly, use the permanent mold casting method at last, water in the copper mold that casts from water-cooled or do not have water-cooled, obtain uniform ingredients, diameter and be 3 millimeters scandium pilum shape bulk amorphous alloys.

After tested, the density of this alloy is 4.214g/cm ³, Young's modulus of elasticity is about 85.2GPa, and specific modulus reaches 20N.m, considerably beyond general Zr base non-crystalline material.And the latter is considered to one of the highest bulk amorphous material of present specific modulus or specific rigidity.

The X-ray diffractogram at this alloy center position is not observed any crystallization peak as shown in Figure 1 in the effective resolution of X-ray diffractometer, have only a wide diffuse scattering peak, illustrates that this alloy is complete non-crystaline amorphous metal.Under transmission electron microscope, observe and confirmed that also this alloy is complete amorphous.Listed dsc analysis result confirms that also the working sample major part is an amorphous in the table 1.In addition, from table 1, also can find reduction glass transformation temperature (T _Rg) and vitrifying index (γ value) all higher, illustrate that the amorphous formation ability of this alloy is fine, as shown in Figure 3, its stronger amorphous formation ability partly cause is that it is near eutectic composition.Glassy alloy density is 4.2g/cm ³About, specific modulus is 20N.m, surpass most of crystalline materials and zirconium-base amorphous material (being about 15N.m) as Vit1, and the latter is considered to one of the highest material of specific modulus and specific tenacity usually, this base amorphous material and other non-crystalline material relatively see Fig. 4, the specific Young's modulus of New type of S c base noncrystal alloy far surpasses famous zirconium-base amorphous alloy as can be seen, and keeps quite high limit recoverable strain, and demonstrating this is that alloy has excellent elastic performance.Second-order transition temperature surpasses other rare earth based bulk amorphous material and most of Zr base massive non-crystalline material, in detail with reference to Fig. 5 and table 1 up to 630-670K.Have wide supercooling liquid phase region width, Tx is 98K.High Tg and wide supercooling liquid phase region mean high thermostability or thermotolerance.

Embodiment 2～11

Prepare the scandium-base large amorphous alloy of various proportionings by the method for embodiment 1, it is formed and thermal physical property parameter is listed in table 1.DSC temperature rise rate: 20K/min.

The composition of table 1, scandium-base large amorphous alloy and thermal physical property parameter

Composition	T g (K)	T x (K)	T m (K)	Tl (K)	T (K)	T rg (K)	γ
								Sc 60Co 20Al 20 Sc 36Co 20Y 20Al 24 Sc 40Co 20Y 20Al 20 Sc 46Y 20Co 20Al 14 Sc 50Co 20Y 20Al 10 Sc 41Co 20Y 15Al 24 Sc 46Co 20Y 10Al 24 Sc 35Co 20Y 20Al 25 Sc 40Co 15Y 20Al 25 Sc 45Co 10Y 20Al 25 Sc 35Co 20Gd 20Al 25	670 662 657 633 632 667 664 660 658 645 650	730 760 743 684 670 750 730 740 748 690 765	1000 970 990 994 950 956 950 945 980 980 985	1100 1048 1051 1053 1052 1045 1100 1115 1045 1042 1052	60 98 86 51 38 83 66 80 90 45 115	0.609 0.632 0.625 0.601 0.601 0.638 0.604 0.592 0.63 0.619 0.618	0.395 0.444 0.435 0.406 0.398 0.438 0.414 0.417 0.439 0.409 0.449

Annotate: 1) T wherein _Rg=T _g/ T _m, γ=T _x/ (T _g+ T _l).

The heat physical properties of the bulk amorphous material of other system of table 2 comparative example

Composition	T g (K)	T x (K)	T m (K)	T l (K)	T (K)	T rg (K)	γ
								Ce 60Cu 20Ni 10Al 10 Gd 40Y 16Al 24Co 20 Dy 40Y 16Al 24Co 20 *Pr 60Cu 20Ni 10Al 10 Nd 60Cu 20Ni 10Al 10 Zr 41Ti 14Cu 12.5Ni 10B e 22.5 Zr 65A l7.5Cu 17.5Ni 10 Pd 40Ni 10Cu 30P 20	374 598 633 409 438 623 656 575	441 653 682 452 478 672 735 670	645 972 1011 705 728 932 1108 804	672 995 1031 806 755 996 1168 840	67 55 49 43 40 49 79 95	0.57 0.60 0.61 0.51 0.58 0.625 0.56 0.68	0.422 0.410 0.409 0.372 0.401 0.415 0.403 0.473

Annotate: DSC temperature rise rate: 10K/min.

By table 1 and table 2 data as can be known, the glass heat stability of different rare earths is different, with reference to comparative example (table 2) as can be known, and Sc ₃₆Co ₂₀Y ₂₀Al ₂₄Has higher relatively thermostability.It is worthy of note that in addition the glass forming ability (GFA) of different systems also is inequality.Rare earth atom electronic structure, atomic size have remarkable influence to the GFA of Sc base large amorphous alloy.Atomic size and its electronic structure, especially closely related with the electronics number of inferior outer 4f electronic shell.Be embodied in the increase along with atomic size (as atom effect volume), GFA increases afterwards earlier and reduces, when atom effect volume is 19cm ³During/mol, the GFA maximum.For example, La-Al-Co-Y can not form large block amorphous.Sm base large amorphous alloy its critical size under the die cast condition can reach about 3mm, and the critical size of Dy base and Er base large amorphous alloy can reach 5～8mm.

Table 3 Sc-BMG and other non-crystalline material elastic constant

Composition	T g (K)	E (GPa)	G (GPa)	B (GPa)
					Sc 36Co 20Y 20Al 24 Dy 46Y 10Al 24Co 18Fe 2 Gd 36Y 20Al 24Co 20 Nd 60Fe 20Ni 10Al 10 Pr 60Al 10Ni 10Cu 20 La 66Al 14Cu 10Ni 10 Ce 70AL 10Ni 10Cu 10	662 627 603 485 417 405 359	85.2 64.2 62.2 54.1 37.2 35.7 30.3	32.3 24.4 23.6 20.7 13.6 13.4 11.5	77.5 58.5 57.4 54.1 45.2 34.9 27.0

Claims (6)

1, a kind of scandium-base large amorphous alloy is to be main component with the scandium, and rare earth is characterized in that as one of basic alloy element, the following formulate of its atom proportioning composition:

Sc _60-xCo ₂₀(Y，Gd) ₂₀Al _x

Or Sc _45-zCo _10+z(Y, Gd) ₂₀Al ₂₅

Or Sc ₄₆Co ₂₀Y ₁₀Al ₂₄Or Sc ₄₁Co ₂₀Y ₁₅Al ₂₄

X=14～25 wherein, z=5～10.

2, scandium-base large amorphous alloy as claimed in claim 1 is characterized in that, the purity of described rare earth Sc, Y and Gd is not less than 90at%.

3, scandium-base large amorphous alloy as claimed in claim 2 is characterized in that, described scandium-base large amorphous alloy comprises at least 50% volume percent amorphous phase.

4, the preparation method of the described scandium-base large amorphous alloy of a kind of claim 1 comprises the steps:

1) according to

Sc _60-xCo ₂₀(Y，Gd) ₂₀Al _x

Or Sc _45-zCo _10+z(Y, Gd) ₂₀Al ₂₅

Or Sc ₃₆Co ₂₀Y ₂₀Al ₂₄Or Sc ₄₁Co ₂₀Y ₁₅Al ₂₄

Atom proportioning ratio prepare raw material, x=14～25 wherein, z=510;

2) in the electric arc furnace of the argon atmospher of titanium absorption, by needed atom proportioning with above-mentioned component mix, melting is even;

3) use the permanent mold casting method, water and cast from the metal pattern, obtain scandium-base large amorphous alloy.

5, the preparation method of the scandium-base large amorphous alloy of stating as claim 4 is characterized in that the purity of described rare earth Sc, Y and Gd is not less than 90at%.

6, the preparation method of the scandium-base large amorphous alloy of stating as claim 5 is characterized in that described metal pattern is no water-cooled or water-cooled metal mould.

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