Effect of Zr addition on the glass-forming ability and mechanical properties of Ni–Nb alloy

The effect of zirconium (Zr) addition on the glass-forming ability (GFA) and mechanical properties of the Ni61.5Nb38.5 alloy has been studied. The addition of Zr improves the GFA. When x = 5 for Ni61.5Nb38.5−xZrx (in at.%) alloys, the alloy exhibits the best GFA and can be cast into 3-mm-diameter amorphous samples by using the copper mold injection-casting method. Differential scanning calorimetry measurements indicated that the thermal parameters, such as Trg and γ, have not a good correlation with the GFA in the Ni–Nb–Zr alloys. Compression tests reveal that the addition of Zr just decreases the fracture strength slightly from 3.4 to 3 GPa and that all of the tested samples exhibit a little compressive plasticity of about 2%. When x = 9, the feature of the fracture surface indicates that the alloy has a tendency for transition from the ductile to the brittle. And delicate “dimple” and microscale vein pattern structures have been observed on it.

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Glass-forming ability, phase formation and mechanical properties of glass-forming Cu-Hf-Zr alloys

Progress in Natural Science Materials International ◽

10.1016/j.pnsc.2019.08.009 ◽

2019 ◽

Vol 29 (5) ◽

pp. 576-581

Author(s):

K. Kosiba ◽

Kaikai Song ◽

U. Kühn ◽

Gang Wang ◽

S. Pauly

Keyword(s):

Mechanical Properties ◽

Phase Formation ◽

Glass Forming Ability ◽

Glass Forming ◽

Zr Alloys

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Effect of Co Addition on the Glass-Forming Ability and Mechanical Properties of Ti-Zr-Be-Cu-Co Bulk Amorphous Alloys

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.182-183.203 ◽

2012 ◽

Vol 182-183 ◽

pp. 203-207

Author(s):

Zhong Yuan Suo ◽

Yan Ling Song ◽

Ke Qiang Qiu

Keyword(s):

Mechanical Properties ◽

Glassy Alloy ◽

Glass Forming Ability ◽

Yield Strain ◽

Scanning Calorimetry ◽

High Fracture ◽

Glass Forming ◽

Transmission Electron ◽

Bulk Glassy Alloy ◽

Co Addition

The effect of Co substitution for Be on the glass-forming ability and mechanical properties was investigated in Ti35Zr30Be27.5-xCu7.5Cox (x=0, 3.5, 7.5, 11.5 at.%) alloys by using X-ray diffractometry (XRD), differential scanning calorimetry (DSC), high-resolution transmission electron microscopy (HRTEM) and compression test. With the substitution of Co for Be, glass-forming ability (GFA) is significantly enhanced and fully amorphous rods with a diameter of up to 12 mm were produced in the alloy with 3.5 and 7.5 at.% Co. The Ti35Zr30Be24Cu7.5Co3.5 bulk glassy alloy exhibits good plasticity of 4% during compressive applied load at ambient temperature in conjunction with distinct yield strain of 2% and high fracture strength of 2196 MPa. The effect of the addition of Co on the structure and deformation behavior of the Ti35Zr30Be27.5-xCu7.5Cox (x=0, 3.5, 7.5, 11.5 at.%) alloys is discussed.

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Glass Forming Ability and Thermal Properties of a Cu-Based Bulk Metallic Glass Microalloyed with Silicon

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.1341 ◽

2007 ◽

Vol 561-565 ◽

pp. 1341-1344 ◽

Cited By ~ 2

Author(s):

Jason S.C. Jang ◽

Y.C. Huang ◽

C.H. Lee ◽

I.S. Lee ◽

L.J. Chang

Keyword(s):

Activation Energy ◽

Thermal Properties ◽

Isothermal Annealing ◽

Alloy System ◽

Glass Forming Ability ◽

Casting Method ◽

Scanning Calorimetry ◽

X Ray ◽

Glass Forming ◽

Activation Energy Of Crystallization

The (Cu42Zr42Al8Ag8)100-xSix amorphous alloy rods, x =0 to 1, with 3 mm in diameter were prepared by Cu-mold drop casting method. The glass forming ability, thermal properties and microstructure evolution was studied by differential scanning calorimetry (DSC), and X-ray diffractometry (XRD). The XRD result reveals that these as-quenched (Cu42Zr42Al8Ag8)100-xSix alloy rods exhibit a broaden diffraction pattern of amorphous phase. The crystallization temperature and GFA (glass forming ability) of (Cu42Zr42Al8Ag8)100-xSix alloys increase with the silicon additions. The highest Trg (0.59) and γ value (0.405) occurred at the (Cu42Zr42Al8Ag8)99.75Si0.25 and (Cu42Zr42Al8Ag8)99.5Si0.5 alloy. In addition, both of the activation energy of crystallization and the incubation time of isothermal annealing for these (Cu42Zr42Al8Ag8)100-xSix alloys indicates that the (Cu42Zr42Al8Ag8)99.25Si0.75 alloy posses the best thermal stability among the (Cu42Zr42Al8Ag8)100-xSix alloy system.

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Microstructure and mechanical properties of slowly cooled Zr66.4Nb6.4Cu10.5Ni8.7Al8.0 with ductile bcc phase

MRS Proceedings ◽

10.1557/proc-754-cc11.19 ◽

2002 ◽

Vol 754 ◽

Author(s):

Uta Kühn ◽

Jürgen Eckert ◽

Norbert Mattern ◽

Nicolle Radtke ◽

Ludwig Schultz

Keyword(s):

Mechanical Properties ◽

Cooling Rate ◽

Alloy Composition ◽

Glassy Matrix ◽

Compression Tests ◽

Copper Mold ◽

Glass Forming ◽

Injection Casting ◽

Bcc Phase

ABSTRACTWe report about the preparation and properties of a Be-free Zr66.4Nb6.4Cu10.5Ni8.7Al8.0 alloy with a glassy or a nanocrystalline matrix and ductile bcc precipitates, which were developed with the aim to improve the mechanical properties. The samples were prepared in form of rods by injection casting into a copper mold. The phase formation as well as the resulting microstructure and the mechanical properties of the different samples have been investigated upon cooling from the melt at different quenching rates. The formation of the bcc phase embedded in a glassy matrix is strongly governed by the alloy composition and the actual cooling rate during solidification, because the glass forming ability is much lower compared to Zr-based alloys containing Be. Already small reductions in cooling rate lead to precipitation of additional crystalline phases. Compression tests reveal that the in-situ glassmatrix composite undergoes work hardening and plastic deformation prior to failure. Surprisingly, also a nanocrystalline matrix leads to high elastic strain values. These features significantly improve the mechanical behavior of the composites compared to the monolithic glass.

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Effects of High Co Contents in Fe-Cr-Mo-C-B-Y Alloy on the Glass Forming and the Mechanical Properties

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.652-654.1054 ◽

2013 ◽

Vol 652-654 ◽

pp. 1054-1058 ◽

Cited By ~ 1

Author(s):

Qing Jun Chen ◽

Jiang Lie Liu ◽

Xian Liang Zhou ◽

Jun Shen ◽

Xiao Zhen Hua

Keyword(s):

Mechanical Properties ◽

Thermal Conductivity ◽

Thermal Diffusivity ◽

Metallic Glasses ◽

Amorphous Region ◽

Glass Forming Ability ◽

Copper Mold ◽

Casting Method ◽

Glass Forming ◽

Wedge Shape

A series of wedge shape Fe24+XCo24-XCr15Mo14C15B6Y2 (x=0,2,4,6,8) samples were prepared by copper mold suction casting method. The effects of high Co contents on glass forming ability (GFA) and mechanical properties of Fe24+XCo24-X Cr15Mo14C15B6Y2 bulk metallic glasses (BMG) were investigated, respectively. The glass forming ability of bulk amorphous Fe24+XCo24-XCr15Mo14C15B6Y2 (x=0,2,4,6,8) and Fe41Co7Cr15Mo14C15B6Y2 alloys have been researched. Simultaneously, the thermal conductivity parameters of those alloys were tested. The maximum thickness of amorphous region of wedge-shaped samples are dm =7.80 mm for Fe28Co20Cr15Mo14C15B6Y2, dm =7.10 mm for Fe41Co7Cr15Mo14C15B6Y2 and the thermal conductivity are λ=7.11 w.m-1.k-1 and 7.19 w.m-1.k-1, the thermal diffusivity are α=1.875 mm2/s and 1.905 mm2/s for Fe28Co20Cr15Mo14C15B6Y2 and Fe41Co7Cr15Mo14C15B6Y2 BMGs, respectively. The glass forming ability of Fe28Co20Cr15Mo14C15B6Y2 alloy is bigger than that of well known Fe41Co7Cr15Mo14C15B6Y2 alloy. With the change of Co content, the Vickers hardness of Fe24+XCo24-XCr15Mo14C15B6Y2 (x=0,2,4,6,8) change from 1292 to 1322Hv.

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