Effect of Charge Voltage on the Microstructural, Mechanical, and Tribological Properties of Mo–Cu–V–N Nanocomposite Coatings

As an important high-power impulse magnetron sputtering (HIPIMS) parameter, charge voltage has a significant influence on the microstructure and properties of hard coatings. In this work, the Mo–Cu–V–N coatings were prepared at various charge voltages using HIPIMS technique to study their mechanical and tribological properties. The microstructure was analyzed by scanning electron microscope (SEM), X-ray diffraction (XRD), and transmission electron microscopy (TEM). The mechanical and tribological properties were investigated by nano-indentation and ball-on-disc tribometer. The results revealed that all the coatings showed a solid-solution phase of B1-MoVN, the V atoms dissolved into face-centered cubic (FCC) B1-MoN lattice by partial substitution of Mo, and formed a solid-solution phase. Even at a high Cu content (~8.8 at. %), the Cu atoms existed as an amorphous phase. When the charge voltage increased, more energy was put into discharge, and the microstructure changed from coarse structure into dense columnar structure, resulting in the highest hardness of 28.2 GPa at 700 V. An excellent wear performance with low friction coefficient of 0.32 and wear rate of 6.3 × 10−17 m3/N·m was achieved at 750 V, and the wear mechanism was dominated by mild abrasive and tribo-oxidation wear.

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TENSILE AND COMPRESSIVE MECHANICAL BEHAVIOR OF A CoCrCuFeNiAl0.5 HIGH ENTROPY ALLOY

International Journal of Modern Physics B ◽

10.1142/s0217979209060774 ◽

2009 ◽

Vol 23 (06n07) ◽

pp. 1254-1259 ◽

Cited By ~ 53

Author(s):

FANGJUN WANG ◽

YONG ZHANG ◽

GUOLIANG CHEN ◽

HYWEL A. DAVIES

Keyword(s):

Solid Solution ◽

Solution Phase ◽

High Entropy Alloy ◽

Solid Solution Phase ◽

Face Centered Cubic ◽

Compressive Properties ◽

Large Plastic Strain ◽

High Entropy ◽

Strain Limit ◽

Face Centered

A high entropy alloy of composition CoCrCuFeNiAl 0.5 is mainly composed of a face centered cubic (FCC) solid solution phase. The tensile and compressive properties of the alloy were investigated; the alloy exhibited a tensile strength of 707 MPa, together with a large plastic strain limit of 19%.

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Transition alpha structure in beta-isomorphous Nb-Hf alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126068 ◽

1987 ◽

Vol 45 ◽

pp. 232-233

Author(s):

R.W. Carpenter ◽

Changhai Li ◽

David J. Smith

Keyword(s):

Solid Solution ◽

Solution Phase ◽

Miscibility Gap ◽

Large Strains ◽

Solid Solution Phase ◽

Two Phase ◽

Diffuse Intensity ◽

Metastable Form ◽

The Matrix ◽

Equilibrium Morphology

Binary Nb-Hf alloys exhibit a wide bcc solid solution phase field at temperatures above the Hfα→ß transition (2023K) and a two phase bcc+hcp field at lower temperatures. The β solvus exhibits a small slope above about 1500K, suggesting the possible existence of a miscibility gap. An earlier investigation showed that two morphological forms of precipitate occur during the bcc→hcp transformation. The equilibrium morphology is rod-type with axes along <113> bcc. The crystallographic habit of the rod precipitate follows the Burgers relations: {110}||{0001}, <112> || <1010>. The earlier metastable form, transition α, occurs as thin discs with {100} habit. The {100} discs induce large strains in the matrix. Selected area diffraction examination of regions ∼2 microns in diameter containing many disc precipitates showed that, a diffuse intensity distribution whose symmetry resembled the distribution of equilibrium α Bragg spots was associated with the disc precipitate.

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Non-equilibrium Ti-Fe bulk alloys with ultra-high strength and enhanced ductility

MRS Proceedings ◽

10.1557/proc-851-nn5.13 ◽

2004 ◽

Vol 851 ◽

Author(s):

Dmitri V. Louzguine-Luzgin ◽

Larissa V. Louzguina-Luzgina ◽

Hidemi Kato ◽

Akihisa Inoue

Keyword(s):

Solid Solution ◽

Supersaturated Solid Solution ◽

High Strength ◽

Eutectic Structure ◽

Solution Phase ◽

Solid Solution Phase ◽

Mechanical Fracture ◽

Glassy Alloys ◽

Fe Alloys ◽

Bulk Alloys

ABSTRACTThe high-strength and ductile hypo-, hyper- and eutectic Ti-Fe alloys were formed in the shape of the arc-melted ingots with the dimensions of about 25–40 mm in diameter and 10–15 mm in height. The structure of the samples consists of cubic Pm 3 m TiFe and BCC Im 3 m β-Ti supersaturated solid solution phase. The arc-melted hypereutectic Ti65Fe35 alloy has a dispersed structure consisting of the primary TiFe phase and submicron-size eutectic structure. This alloy exhibits excellent mechanical properties: a Young's modulus of 149 GPa, a high mechanical fracture strength of 2.2 GPa, a 0.2 % yield strength of 1.8 GPa and 6.7 % ductility. The hard round-shaped intermetallic TiFe phase and the supersaturated β-Ti solid solution result in a high strength of the Ti65Fe35 alloy which in addition has much higher ductility compared to that of the nanostructured or glassy alloys. The reasons for the high ductility of the hypereutectic alloy are discussed.

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Effects of hydrogen on the microstructure and microchemistry of Ti3Al – Nb intermetallics at high temperatures and high pressures

Journal of Materials Research ◽

10.1557/jmr.1996.0278 ◽

1996 ◽

Vol 11 (9) ◽

pp. 2186-2197 ◽

Cited By ~ 5

Author(s):

H. Z. Xiao ◽

I. M. Robertson ◽

H. K. Birnbaum

Keyword(s):

Solid Solution ◽

High Temperatures ◽

High Pressures ◽

Chemical Potential ◽

Substitutional Solid Solution ◽

Hydrogen Gas ◽

Solid Solution Phase ◽

Face Centered Cubic ◽

Fine Grained ◽

Surrounding Matrix

The microstructural and microchemical changes produced in a Ti–25Al–10Nb–3V–1Mo alloy (at. %) by charging at high temperatures in high pressures of hydrogen gas have been studied using transmission electron microscopy (TEM) and x-ray methods. Hydrides incorporating all of the substitutional solutes that formed during charging have a face-centered cubic (fcc) structure and exhibit either a plate or fine-grained morphology. With increasing hydrogen content, the size of the hydrides decreases and their microchemistry changes as they approach the stable binary hydride, TiH2. Rejection of substitutional solute elements from the hydride produces changes in the microchemistry, and consequently in the crystal structure, of the surrounding matrix. In alloys containing 50 at. % H, this solute redistribution results in the formation of an orthohombic substitutional solid solution phase containing increased levels of Nb. The driving force of this redistribution of solutes is the reduction in the chemical potential of the system as the amount of the most stable hydride, TiH2, forms. The hydrides reverted to a solid solution on annealing in vacuum at 1073 K, and the original microchemistry of the alloy was restored. Reversion from the hydride structure to the original α2 ordered DO19 structure proceeds via a disordered HCP phase.

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Detailed Phase Analysis and Crystal Structure Investigation of a Bi1−xCaxFeO3−x/2Perovskite-Related Solid Solution Phase and Selected Property Measurements Thereof

Chemistry of Materials ◽

10.1021/cm901757h ◽

2009 ◽

Vol 21 (18) ◽

pp. 4223-4232 ◽

Cited By ~ 39

Author(s):

Jason Schiemer ◽

Ray Withers ◽

Lasse Norén ◽

Yun Liu ◽

Laure Bourgeois ◽

...

Keyword(s):

Crystal Structure ◽

Solid Solution ◽

Phase Analysis ◽

Solution Phase ◽

Solid Solution Phase ◽

Structure Investigation

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Nanocrystalline Ni-30wt%Fe Supersaturated Solid Solution Synthesized by Mechanical Alloying

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.490-491.38 ◽

2014 ◽

Vol 490-491 ◽

pp. 38-42

Author(s):

Yu Chen ◽

Yang Yu ◽

Wen Cong Zhan ◽

Er De Wang

Keyword(s):

Solid Solution ◽

Crystallite Size ◽

Powder Mixture ◽

Supersaturated Solid Solution ◽

Average Crystallite Size ◽

Solution Phase ◽

Elemental Powder ◽

Solid Solution Alloy ◽

Solid Solution Phase ◽

Elemental Powder Mixture

Ni-30wt%Fe elemental power mixture was mechanically milled under argon atmosphere for variuos times up to 25h.The evolution of Ni-Fe alloying during milling and the microstructure of the as-milled powders were characterized by XRD, EPMA (electron probe microanalysis), SEM and TEM, respectively. The results show that nanocrystalline Ni (Fe) supersaturated solid solution alloy powders with 30wt. % Fe in composition can be synthesized by mechanical milling of the elemental powder mixture. Both the content of Fe dissolved and the microstrain developed in the as-synthesized Ni (Fe) solid solution phase increase, while the crystallite size decreases, steadily with increasing milling time. In particular, the Ni-30wt%Fe alloy powders obtained by 25h milling consist of a single Ni (Fe) supersaturated solid solution phase with average crystallite size of about 15nm and accumulated microstrain as high as 1.12%. DSC tests show that the nanocrystalline Ni-30wt%Fe alloy powders have a lower melting temperature than the elemental powder mixture, attributed to the unique Ni (Fe) solid solution phase structure, the nanocrystallization, and the high strain energy.

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Phase stability in high entropy alloys: Formation of solid-solution phase or amorphous phase

Progress in Natural Science Materials International ◽

10.1016/s1002-0071(12)60080-x ◽

2011 ◽

Vol 21 (6) ◽

pp. 433-446 ◽

Cited By ~ 690

Author(s):

Sheng GUO ◽

C.T. LIU

Keyword(s):

Solid Solution ◽

Amorphous Phase ◽

Phase Stability ◽

Solution Phase ◽

Solid Solution Phase ◽

High Entropy Alloys ◽

High Entropy

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Interaction between Two Ni-Base Alloys and Ceramic Moulds

Materials Science Forum ◽

10.4028/www.scientific.net/msf.747-748.765 ◽

2013 ◽

Vol 747-748 ◽

pp. 765-771 ◽

Cited By ~ 7

Author(s):

Jian Sheng Yao ◽

Ding Zhong Tang ◽

Xiao Guang Liu ◽

Cheng Bo Xiao ◽

Xin Li ◽

...

Keyword(s):

Solid Solution ◽

Interface Reaction ◽

Vapour Phase ◽

Optical Microscope ◽

Solution Phase ◽

Solid Solution Phase ◽

X Ray Diffraction ◽

X Ray ◽

Scanning Electron ◽

Reaction Surfaces

The interfacial reactions between ceramic moulds and DZ417G and DZ125 superalloys were investigated. The microstructure and composition of the interface region were observed by optical microscope, X-ray diffraction and scanning electron microscope with energy dispersive spectroscopy. The results showed that (Al1-xCrx)2O3solid solution phase with pink color was formed from the dissolution of Cr2O3and Al2O3and vapour phase, which was transferred to the reaction surfaces. The reaction layer thicknesses of DZ417G and DZ125 alloys were about in the range of 40-50μm. The interface reaction product between DZ417G alloy and ceramic mould was TiO2and the product between DZ125 alloy and ceramic mould was HfO2.

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