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Alloy Substrates (alloy + substrate)

Distribution by Scientific Domains
Polymers and Materials Science75%

Selected Abstracts

Microstructural and Mechanical Investigations on Porcelain-Fused-to-Metal in Multilayer System

ADVANCED ENGINEERING MATERIALS, Issue 4 2010
Adele Carraḍ
Results on porcelain-fused-to-metal (PFM) technique of ceramic films for biomedical applications on metal substrate are reported. The coating of metallic implants with bio-ceramic films (glassy and opaque ceramic) was proposed to be a solution for combining the mechanical properties of the metallic material with the bioactive character of the ceramic layer, leading to a better integration of the entire implant. The aim of this paper is to determine a stress field distribution by a non-destructive method as high-energy synchrotron X-ray diffraction in energy dispersive in the metal and glass ceramic bulk as well as at metal,opaque ceramic interface in PFM three layers sample. Tensile stresses were found in palladium substrate and compressive state in glass ceramic coating. Moreover thermal stresses induced by PFM coating at the interfaces were calculated by analytical mathematical model, confirming that the stresses induced, due to the selection of the materials, are low. Finally, the micro-structural and chemical characteristics of glassy and opaque bio-ceramic coatings on palladium alloy substrate were investigated and no inter-diffusion area between metal and ceramic could be detected as well as non-homogeneity in the interface ceramic. [source]

SiO2 -CaO Vitreous Films Deposited onto Ti6Al4V Substrates

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 8 2003
Isabel Izquierdo-Barba
Abstract A sol-gel dipping method has been utilised to deposit SiO2 -CaO films onto Ti6Al4V alloy substrates. These layers were prepared by the dip-coating technique from a series of precursor solutions with different concentrations of glassy xSiO2 -(1 , x)CaO (x = 0.8 mol) diluted with absolute ethanol. The characterisation of the films by a variety of techniques reveals differences in the textural properties and in the films' thicknesses depending on the sol concentration in the precursor solution. Concentrated precursor solutions yield porous layers with a higher thickness and surface roughness than those obtained from the dilute ones. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source]

Modeling of Coating Process, Phase Changes, and Damage of Plasma Sprayed Thermal Barrier Coatings on Ni-Base Superalloys,

ADVANCED ENGINEERING MATERIALS, Issue 3 2010
Tilmann Beck
The paper gives an overview on the modeling activities on plasma sprayed thermal barrier coating in the frame of TFB 63. In the first part, through-process modeling of the APS deposition of a ZrO2 based TBC is described. Starting from simulation of the plasma jet, heat transfer into the powder particles, particle melting, particle impact on the substrate surface, and solidification is simulated. A homogenization method is introduced to describe the mechanical properties of the resulting TBC. The second part shows simulation of interdiffusion and phase transformations of MCrAlY and intermetallic oxidation protection coatings on several cast Ni-base alloy substrates. Finally, FEM-based damage simulation of oxidation protection coatings by transversal fatigue cracks during thermomechanical fatigue loading as well as by delamination of the TBC during thermocyclic loading is discussed. [source]

Design of Experiments (DOE) for the Optimization of Titania,hydroxyapatite Functionally Graded Coatings

INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 4 2009
Valeria Cannillo
Titania,hydroxyapatite functionally graded coatings were deposited on titanium alloy substrates by plasma spraying. Because it was necessary to spray together the titania and the hydroxyapatite powders to obtain the graded system, the first target of the present study was to optimize the process parameters in order to obtain a high-quality coating. A 23 Design of Experiments was applied to define the optimal values of plasma torch power, hydrogen flux, and spraying distance. This defined set of parameters (38 kW, 5 SLPM, and 90 mm, respectively) was used to spray the most promising graded coating, which was characterized and postheat treated. [source]