Comparative Study of Creep Resistance of a Ti-6Al-4V Alloy with Metallic and Ceramic Coatings

Titanium and its alloys are largely used for many industrial applications due to their high mechanical and corrosion resistance and low specific mass. Ti-6Al-4V alloy is the most used in aerospace industry and it is applied for the manufacturing of aircraft blades and steam turbines. This alloy has high affinity with oxygen which constrains its application at high temperatures due to creep resistance reduction. Methods to increase creep resistance of Ti-6Al-4V alloys includes the use of metallic coatings and its combination with ceramic thermal barrier coating deposition on the material surface. The aim of this work is to compare the creep behavior of Ti-6Al-4V alloy in three different conditions: uncoated, metallic coated, metallic + ceramic coated specimens. The metallic coating layer (CoNiCrAlY) and the ceramic coating (ZrO2+ 8wt%Y2O3) are both applied by plasma spray deposition technique. The specimens were submitted to constant load creep tests at 600oC and stress conditions of 125, 250 and 319MPa. Specimens of metallic + ceramic coating have presented higher creep resistance, longer lifetime and lower stationary creep rate when compared to uncoated and metallic coated specimens.

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Comparation between Pulsed Nd:YAG Laser Superficial Treatment and Ceramic Coating in Creep Test of Ti-6-4V Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.660-661.229 ◽

2010 ◽

Vol 660-661 ◽

pp. 229-234 ◽

Cited By ~ 1

Author(s):

Adriano G. Reis ◽

Danieli A.P. Reis ◽

Carlos de Moura Neto ◽

Javier Onõro ◽

H.S. Oliveira ◽

...

Keyword(s):

Laser Treatment ◽

Creep Test ◽

Nd:Yag Laser ◽

Creep Resistance ◽

Ceramic Coating ◽

Constant Load ◽

Creep Tests ◽

Pulsed Nd:Yag Laser ◽

Load Mode ◽

Plasma Sprayed

The objective of this work was evaluating the creep resistance of the Ti-6Al-4V alloy with superficial treatment of pulsed Nd:YAG laser and ceramic coating in creep test of Ti-6Al-4V alloy. It was used Ti-6Al-4V alloy as cylindrical bars under forged and annealing of 190oC by 6 hours condition and cooled by air. The Ti-6Al-4V alloy after the superficial treatment of pulsed Nd:YAG laser and ceramic coating was submitted to creep tests at 600°C and 125 at 319 MPa, under constant load mode. In the Nd:YAG pulsed laser treatment was used an environment of 40 % N and 60 % Ar, with 2.1 W of power and 10 m/s of speed. Yttria (8 wt.%) stabilized zirconia (YSZ) with a CoNiCrAlY bond coat was atmospherically plasma sprayed on Ti-6Al-4V substrates by Sulzer Metco Type 9 MB. The obtained results suggest the laser treatment on Ti-6Al-4V alloy improved its creep resistance.

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Evaluation of Heat Treatment and Ceramic Coating in Creep of Ti-6Al-4V

Materials Science Forum ◽

10.4028/www.scientific.net/msf.660-661.235 ◽

2010 ◽

Vol 660-661 ◽

pp. 235-240 ◽

Cited By ~ 2

Author(s):

Tarcila Sugahara ◽

L.A.N.S. Briguente ◽

L.M. Yogi ◽

Danieli A.P. Reis ◽

Carlos de Moura Neto ◽

...

Keyword(s):

Heat Treatment ◽

Creep Resistance ◽

Stress Condition ◽

Ceramic Coating ◽

High Stress ◽

Life Time ◽

Constant Load ◽

Stabilized Zirconia ◽

Creep Tests ◽

Plasma Sprayed

This study aimed to evaluate the resistance of a Ti-6Al-4V alloy in creep after heat treatments. It was used a Ti-6Al-4V alloy in cylindrical bars forms, forged condition and annealing at 190oC for 6 hours and cooled in air. The microstructure of Ti-6Al-4V alloy was evaluated after heat treatment and was submitted to creep tests at 600oC and stress conditions from 125 to 319 MPa at constant load. The Widmanstätten structure was obtained by heat treatment. Yttria (8 wt.%) stabilized zirconia (YSZ) with a CoNiCrAlY bond coat was atmospherically plasma sprayed on Ti-6Al-4V substrates by Sulzer Metco Type 9 MB. The alloy with Widmanstätten structure and ceramic coating shows greater resistance to creep and oxidation with a longer life time in creep. At higher stress condition, 600°C and 319 MPa, the Ti-6Al-4V alloy with ceramic coating didn’t show higher creep resistance. This condition presented higher tp value and the value. It occurred because at high stress condition the coating is very fragile, decreasing your creep resistance.

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Comparation between PIII Superficial and Ceramic Coating in Creep Test of Ti-6Al-4V Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.660-661.225 ◽

2010 ◽

Vol 660-661 ◽

pp. 225-228

Author(s):

Danieli A.P. Reis ◽

Carlos de Moura Neto ◽

M.M. Silva ◽

Mario Ueda ◽

V.S. Oliveira ◽

...

Keyword(s):

Creep Test ◽

Creep Resistance ◽

Ceramic Coating ◽

Constant Load ◽

Creep Tests ◽

Time Intervals ◽

Treat Ment ◽

Load Mode ◽

Nitrogen Ions ◽

Plasma Sprayed

The objective of this work was evaluating the creep resistance of the Ti-6Al-4V alloy with superficial treatment of PIII superficial treatment and ceramic coating in creep test of Ti-6Al-4V alloy. It was used Ti-6Al-4V alloy as cylindrical bars under forged and annealing of 190oC by 6 hours condition and cooled by air. The Ti-6Al-4V alloy after the superficial treat-ment of PIII and ceramic coating was submitted to creep tests at 600°C and 250 and 319 MPa under constant load mode. In the PIII treatment the samples was put in a vacuum reactor (76x10-3 Pa) and implanted by nitrogen ions in time intervals between 15 and 120 minutes. Yttria (8 wt.%) stabilized zirconia (YSZ) with a CoNiCrAlY bond coat was atmospherically plasma sprayed on Ti-6Al-4V substrates by Sulzer Metco Type 9 MB. The obtained results suggest the ceramic coating on Ti-6Al-4V alloy improved its creep resistance.

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A Comparison between CoNiCrAlY Bond Coat and Zirconia Plasma Sprayed Coatings on Creep Tests

Materials Science Forum ◽

10.4028/www.scientific.net/msf.591-593.30 ◽

2008 ◽

Vol 591-593 ◽

pp. 30-35

Author(s):

Danieli A.P. Reis ◽

Carlos de Moura Neto ◽

Antônio Augusto Couto ◽

Cosme Roberto Moreira Silva ◽

Francisco Piorino Neto ◽

...

Keyword(s):

Bond Coat ◽

Ceramic Coating ◽

Constant Load ◽

Creep Tests ◽

Engineering Ceramic ◽

Wide Range ◽

Plasma Sprayed Coatings ◽

Plasma Sprayed ◽

Engine Components ◽

Sprayed Coatings

Thermomechanical and electrical properties of zirconia-based ceramics have led to a wide range of advanced and engineering ceramic applications like solid electrolyte in oxygen sensors, fuel cells and furnace elements and its low thermal conductivity has allowed its use for thermal barrier coatings for aerospace engine components. A comparison between CoNiCrAlY bond coat and zirconia plasma sprayed coatings on creep tests of the Ti-6Al-4V alloy was studied. The material used was commercial Ti-6Al-4V alloy. Yttria (8 wt.%) stabilized zirconia (YSZ) with a CoNiCrAlY bond coat was atmospherically plasma sprayed on Ti-6Al-4V substrates by Sulzer Metco Type 9 MB. Constant load creep tests were conducted on a standard creep machine in air on coated samples, at stress levels of 520 MPa at 500°C to evaluate the oxidation protection on creep of the Ti-6Al-4V alloy. Results indicate that the creep resistance of the ceramic coating was greater than metallic coating.

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Influence of Zirconia Plasma-Sprayed Coating on Creep of the Ti-6Al-4V Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.530-531.690 ◽

2006 ◽

Vol 530-531 ◽

pp. 690-695 ◽

Cited By ~ 3

Author(s):

Danieli A.P. Reis ◽

Cosme Roberto Moreira Silva ◽

Maria do Carmo de Andrade Nono ◽

M.J.R. Barboza ◽

Francisco Piorino Neto ◽

...

Keyword(s):

Creep Resistance ◽

Surface Oxidation ◽

Constant Load ◽

Nitrogen Atmosphere ◽

High Temperature Strength ◽

Secondary Creep ◽

Creep Tests ◽

Oxidation Protection ◽

Sprayed Coating ◽

Plasma Sprayed

The titanium affinity by oxygen is one of main factors that limit the application of their alloys as structural materials at high temperatures. Notables advances have been obeserved in the development of titanium alloys with the objective of improving the specific high temperature strength and creep-resistance properties. However, the surface oxidation limits the use of these alloys in temperatures up to 600°C. The objective of this work was estimate the influence of the plasma-sprayed coatings for oxidation protection on creep of the Ti-6Al-4V alloy, focusing on the determination of the experimental parameters related to the primary and secondary creep states. Constant load creep tests were conducted with Ti-6Al-4V alloy in air for coated and uncoated samples and in nitrogen atmosphere for uncoated samples at 500°C to evaluate the oxidation protection on creep of the Ti-6Al-4V alloy. Yttria (8 wt.%) stabilized zirconia (YSZ) with a CoNiCrAlY bond coat was atmospherically plasma sprayed on Ti-6Al-4V specimens. Results indicated the creep resistance of the coated alloy was greater than uncoated in air, but nitrogen atmosphere was more efficient in oxidation protection. Previously reported results about the activation energies and the stress exponents values indicate that the primary and stationary creep, for both test conditions, was probably controlled by dislocation climb. Occurred a decreasing of steady state creep in function of the reduction of oxidation process, showing that Ti-6Al-4V alloy lifetime was strongly affected by the atmosphere due the oxidation suffered by the material.

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Determination of Creep Parameters of Ti-6Al-4V with Bimodal and Equiaxed Microstructure

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.326-328.520 ◽

2012 ◽

Vol 326-328 ◽

pp. 520-524 ◽

Cited By ~ 4

Author(s):

L.A.N.S. Briguente ◽

Antônio Augusto Couto ◽

Nara Miranda Guimarães ◽

Danieli A.P. Reis ◽

Carlos de Moura Neto ◽

...

Keyword(s):

Creep Resistance ◽

Room Temperature ◽

Life Time ◽

Constant Load ◽

Bimodal Microstructure ◽

Creep Tests ◽

Equiaxed Microstructure ◽

Specific Strength ◽

Heat Treated

Ti-6Al-4V is the most used of titanium alloy and presents some important properties as metallurgical stability, high specific strength, corrosion and creep resistance [. The aim of this study is to evaluate the creep behavior of Ti-6Al-4V alloy with equiaxed and bimodal microstructures and determine the creep parameters of Ti-6Al-4V in these conditions. It was used a Ti-6Al-4V alloy forged and annealed at 190°C for 6 hours and cooled in air. The material in this condition shows an equiaxed microstructure. For bimodal microstructure, the material was heat-treated at 950°C for 60 minutes and cooled in water until room temperature. After this the material was heat-treated at 600°C for 24 hours and cooled in air until room temperature. Creep tests were performed at 600°C in stress conditions of 125, 250 and 319 MPa at constant load. The alloy with Bimodal microstructure shows higher creep resistance with a longer life time in creep.

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Effect of Long-Term Aging and Creep Exposure on the Microstructure of TiAl-Based Alloy for Industrial Applications

MRS Proceedings ◽

10.1557/proc-842-s7.11 ◽

2004 ◽

Vol 842 ◽

Author(s):

Juraj Lapin ◽

Mohamed Nazmy ◽

Marc Staubli

Keyword(s):

Chemical Composition ◽

Constant Load ◽

Industrial Applications ◽

Tensile Creep ◽

Creep Tests ◽

Fine Needle ◽

Term Creep ◽

Applied Stresses ◽

Creep Exposure

ABSTRACTThe effect of long-term aging and creep exposure on the microstructure of a cast TiAl-based alloy with nominal chemical composition Ti-46Al-2W-0.5Si (at.%) was studied. The aging experiments were performed at temperatures between 973 and 1073 K for various times ranging from 10 to 14000 h in air. Constant load tensile creep tests were performed at applied stresses ranging from 150 to 400 MPa and at temperatures between 973 and 1123 K up to 25677 h. During aging and creep testing the α2(Ti3Al)-phase in the lamellar and feathery regions transforms to the γ(TiAl)-phase and fine needle-like B2 precipitates. Microstructural instabilities lead to a softening of the alloy. The effect of this softening on long-term creep resistance is negligible at temperatures of 973 and 1023 K.

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Tensile Strength and Creep Resistance in Nanocrystalline Cu, Pd and Ag

MRS Proceedings ◽

10.1557/proc-206-581 ◽

1990 ◽

Vol 206 ◽

Cited By ~ 7

Author(s):

G. W. Nieman ◽

J. R. Weertman ◽

R. W. Siegel

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Tensile Strength ◽

Yield Strength ◽

Creep Resistance ◽

Room Temperature ◽

True Strain ◽

Constant Load ◽

Creep Tests ◽

Grain Sizes

ABSTRACTMeasurements of tensile strength and creep resistance have been made on bulk samples of nanocrystalline Cu, Pd and Ag consolidated from powders by cold compaction. Samples of Cu-Cu2O have also been tested. Yield strength for samples with mean grain sizes of 5–80 nm and bulk densities on the order of 95% of theoretical density are increased 2–5 times over that measured in pure, annealed samples of the same composition with micrometer grain sizes. Ductility in the nanocrystalline Cu has exceeded 6% true strain, however, nanocrystalline Pd samples were much less ductile. Constant load creep tests performed at room temperature at stresses of >100 MPa indicate logarithmic creep. The mechanical properties results are interpreted to be due to grain size-related strengthening and processing flaw-related weakening.

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Influence of Application Technology in the Structural Characteristics of Ceramic Coatings with Advanced Anticorrosive and Tribological Properties

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.91.108 ◽

2014 ◽

Vol 91 ◽

pp. 108-116 ◽

Cited By ~ 1

Author(s):

David Vélez ◽

Josemari Muñoz ◽

José Antonio Diez

Keyword(s):

Ceramic Coating ◽

Structural Characteristics ◽

Ceramic Coatings ◽

Industrial Applications ◽

Application Technology ◽

Precise Control ◽

Surface Finishes ◽

Coating Method ◽

Microstructure Morphology

Electrophoretic deposition (EPD) of ceramic frits is shown to be a useful coating method for different metal surfaces and geometries since it allows obtaining very smooth surface finishes with precise control of their thickness. By the other hand, these kind of coatings show differences with the coatings obtained by conventional wet application methods as dipping, flow-coating, slushing and spraying. At this point, CIDETEC has used an own advanced ceramic coating based on no commercial enamels to determinate the best application method to obtain an excellent anticorrosive coating on carbon steel. In view of possible scaling up to particular industrial applications, a detailed characterization of the microstructure, morphology, physical, chemical and mechanical properties of the coatings was performed. The preliminary studies show that EPD system improves the characteristics of this coating.

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