| Development of Al-Cr-X and Al-Cr-Zr-X Alloys by Rapid Solidification from the Melt |
FEB 88 |
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| Authors:
P. Tsakiropoulos; R. C. Pratt; H. Jones; J. E. Restall; R. W. Gardiner
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 | The development of novel aluminum-based engineering alloys with substantial additions of chromium, zirconium and/or manganese by rapid solidification (RS) takes advantage of the ready susceptibility to extension of solid solubility and lowered diffusivities in alpha-Al of these additions compared with, for example, those of iron, cobalt or nickel. The present contribution is concerned with the investigation of some alternatives to X = Zr in Al-Cr-X and to X = Mn ... |
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| Evaluation of the Potential of Low Pressure Plasma Spraying and Simultaneous Spray Peening for Processing of Superalloys |
88 |
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| Authors:
J. V. Wright; J. E. Restall; LUCAS COMBUSTION TECHNOLOGY AND ENGINEERING CENTRE BURNLEY (UNITED KINGDOM)*
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| The potential of low pressure plasma spraying with or without simultaneous peening has been assessed as a means of producing superalloy materials. The equipment and techniques utilized are described and some of the limiting features identified. The quality of the deposits obtained has been investigated using a variety of metallurgical techniques and the structural differences attributable to simultaneous peening are described in detail. Mechanical testing, primarily tensile at ambient and ... |
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| High Temperature Erosion of Coated Superalloys for Gas Turbines, |
APR 1987 |
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| Authors:
J. E. Restall; D. J. Stephenson
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| Particulate materials ingested with the intake air, together with other solids generated within the gas turbine, are known to have the potential of degrading the hot oxidized or corroded surfaces of static and rotating aerofoil components. The nature of the degradation may be primarily by oxidation, corrosion or erosion or through some form of interaction between these processes. These regimes are illustrated by reference to the metallurgical assessment of components ... |
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| Alternative Processes and Treatments, |
MAR 1986 |
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| Authors:
J. E. Restall; M. I. Wood
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| A number of alternative coating processes which can be used to deposit protective coatings on superalloy gas turbine aerofoil components are described. These can be divided into three groups: chemical vapor deposition, non-chemical vapor deposition, and hybrid processes. Their advantages and limitations are discussed relative to current production processes. |
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| The Mechanical Properties of Coated Nickel Based Superalloy Single Crystals |
86 |
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| Authors:
M. I. Wood; J. E. Restall; ROYAL AIRCRAFT ESTABLISHMENT FARNBOROUGH (ENGLAND)
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| The Ni-superalloy substrate single crystals SX60A (Ni-10Co-8.5Cr-10W- 4Ta-5.5Al-1.5Ti) and MMT143 (Ni-14.3Mo-6Ta-5.8Al) were prepared in thin (0.76 mm) and thick (4 mm) strip specimens for coating by plasma deposition with overlayers of Ni-Co-Cr-Al-Y or Co-Cr-Al-Y or by an 85 micron coating of Pt-Al. Specimens were solution heat treated before coating and creep recovery heat treated after coating. Rotating bending fatigue tests were conducted in air at 50 Hz at 400, 600, ... |
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| Development of Coatings for the Protection of Gas Turbine Blades Against High Temperature Oxidation and Corrosion |
OCT 84 |
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| Authors:
J. E. Restall; ROYAL AIRCRAFT ESTABLISHMENT FARNBOROUGH (ENGLAND)
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| An account is given of three techniques that are currently under development for the deposition of overlay-type coatings suitable for protecting superalloy turbine blades and vanes in service engines. These are a combination of plasma spraying with subsequent chemical vapor deposition of aluminum or other elements, sputter ion plating, and occluded electroplating. Results are presented and discussed of various laboratory tests and high velocity corrosion rig tests carried out on ... |
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| Sputter-Ion Plating of Coatings for Protection of Gas-Turbine Blades Against High-Temperature Oxidation and Corrosion |
DEC 82 |
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| Authors:
J. P. Coad; J. E. Restall
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| Considerable effort is being devoted to the development of overlay coatings for protecting critical components such as turbine blades against high- temperature oxidation, corrosion, and erosion damage in service. The most commercially advanced methods for deposititing coatings are electron-beam evaporation and plasma spraying. Sputter-ion plating (SIP) offers a potentially cheaper and simpler alternative method for depositing overlays. Experimental work on SIP of Co-Cr-Al-Y and Ni-Cr-Al-Ti alloy coatings is described. Results ... |
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| High Temperature Erosion and Erosion-Hot Corrosion of Superalloys and Coatings, |
OCT 1982 |
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| Authors:
J. C. Galsworthy; J. E. Restall; G. C. Booth; ADMIRALTY MARINE TECHNOLOGY ESTABLISHMENT POOLE (ENGLAND)
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| Testing methods for erosion and erosion-hot corrosion of superalloys are described and compared. Common turbine component substrates and pack-aluminized, PVD CoCrAlY and precious metal-aluminide coatings are used in illustrations. |
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| A Process for Protecting Gas Turbine Blade Cooling Passages Against Degradation |
80 |
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| Authors:
J. E. Restall; B. J. Gill; C. Hayman; N. J. Archer; NATIONAL GAS TURBINE ESTABLISHMENT FARNBOROUGH (ENGLAND)
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| A new process for the protection of turbine blades and vanes on both external and internal surfaces has been evolved. The surfaces are metallized by pressure-pulsing the coating gases from a near-conventional cementation pack. Penetration occurs into the internal cooling channels which are inaccessible to most other coating processes. Up to 1000 small turbine blades can now be simultaneously pulse aluminized in an industrial plant. |
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| High Temperature Coatings for Protecting Hot Components in Gas Turbine Engines |
NOV 79 |
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| Authors:
J. E. Restall
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| an account is given of the types of materials employed as protective coatings, the methods used for their deposition, and trends in performance demonstrated under engine or corrosion rig test conditions. |
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| The Effects of Salt and Carbon Particles on the Erosion and Corrosion Behaviour of Gas Turbine Materials, |
NOV 1975 |
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| Authors:
J. E. Restall; NATIONAL GAS TURBINE ESTABLISHMENT FARNBOROUGH (ENGLAND)
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| Work was undertaken to assess the erosivity of various graphites, quartz and sea-salt and to determine their role in promoting blade failure. Erosion tests were performed using a whirling-arm rig at room temperature and an air-blast apparatus operating in the range 813K to 873K. A ballistic impact apparatus was also used to implant small particles of graphite and salt in the surface of laboratory testpieces at high temperature. Ingested quartz ... |
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| INFLUENCE OF SALT AND CARBON PARTICLES ON THE BEHAVIOUR OF HOT SUPERALLOY COMPONENTS IN GAS TURBINE ENGINES |
JUN 75 |
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| Authors:
J. E. Restall; NATIONAL GAS TURBINE ESTABLISHMENT FARNBOROUGH (ENGLAND)
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| In the laboratory erosion tests it was shown that dried salt produced a similar level of damage to quartz and pyrolytic carbon on Nimonic 90 alloy and H46 steel at room temperature. Subsequent oxidation exposure of Nimonic 90 alloy testpieces eroded by graphite and sea-salt induced crevice corrosion and sulfidation-corrosion damage at the sites where small particles were still embedded. The brittleness of an oxide film deliberately grown, and that ... |
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| CAST NICKEL SUPERALLOYS FOR HIGH-TEMPERATURE APPLICATIONS IN GAS-TURBINE ENGINES |
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| Authors:
J. E. Restall; E. C. Toulson
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| CAST NICKEL SUPERALLOYS FOR HIGH-TEMPERATURE APPLICATIONS IN GAS-TURBINE ENGINES--PART 2, |
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| Authors:
J. E. Restall; E. C. TOULSON
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Reports by Author
