Waspaloy is a registered trademark of United Technologies Corp [1] that refers to an age hardening austenitic (face-centred cubic) nickel-based superalloy. Waspaloy is typically used in high temperature applications, particularly in gas turbines.
Waspaloy is a registered trademark of United Technologies Corp [1] that refers to an age hardening austenitic (face-centred cubic) nickel-based superalloy. Waspaloy is typically used in high temperature applications, particularly in gas turbines.
Nickel 58%, chromium 19%, cobalt 13%, molybdenum 4%, titanium 3%, aluminium 1.4% [2]
| Cr | Ni | Mo | Co | Al | Ti | B | C | Zr | Fe | Mn | Si | P | S | Cu | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| MIN | 18.00 | -- | 3.50 | 12.00 | 1.20 | 2.75 | 0.003 | 0.02 | 0.02 | -- | -- | -- | -- | -- | -- |
| MAX | 21.00 | Balance | 5.00 | 15.00 | 1.60 | 3.25 | 0.01 | 0.10 | 0.08 | 2.00 | 0.10 | 0.15 | 0.015 | 0.015 | 0.10 |
Waspaloy is an age-hardenable, nickel-based superalloy with excellent strength properties through temperatures of roughly 980°C (1800°F). Other characteristics of Waspaloy include good corrosion resistance, as well as being relatively impervious to oxidation making it well suited for service in extreme environments. [4]
Waspaloy has useful strength at temperatures up to 760-870°C (1400-1600°F), and good oxidation resistance in gas turbine engine atmospheres up to 870°C (1600°F). The creep rupture strength of Waspaloy is superior to that of Alloy 718 at temperatures above 620-650°C (1150-1200°F). Short time hot tensile strength is inferior to RA718 at temperatures up to 730°C (1350°F). [3]
Waspaloy is often used in extreme environments. It is common in gas turbine blades, seals, rings, shafts and turbine disks. [3] The NIST certified reference material 1243, a standard for X-ray fluorescence spectroscopy, is made from Waspaloy. [5]
The British Aircraft Corporation TSR-2, a supersonic strike aircraft developed from the late 1950s, had a fairing to its rear fuselage around the exhaust nozzles. Owing to the high temperatures in this area, the fairing was formed of Waspaloy and left unpainted. Fabrication of this alloy was described as 'very intractable' and was carried out by the engine specialists Bristol, rather than the airframe builders BAC. [6]
An alloy is a mixture of chemical elements of which at least one is a metal. Unlike chemical compounds with metallic bases, an alloy will retain all the properties of a metal in the resulting material, such as electrical conductivity, ductility, opacity, and luster, but may have properties that differ from those of the pure metals, such as increased strength or hardness. In some cases, an alloy may reduce the overall cost of the material while preserving important properties. In other cases, the mixture imparts synergistic properties to the constituent metal elements such as corrosion resistance or mechanical strength.
Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys. Metallurgy encompasses both the science and the technology of metals; that is, the way in which science is applied to the production of metals, and the engineering of metal components used in products for both consumers and manufacturers. Metallurgy is distinct from the craft of metalworking. Metalworking relies on metallurgy in a similar manner to how medicine relies on medical science for technical advancement. A specialist practitioner of metallurgy is known as a metallurgist.
Stainless steel is any one of a group of ferrous alloys that contain a minimum of approximately 11% chromium, a composition that prevents the iron from rusting and also provides heat-resistant properties. Different types of stainless steel include the elements carbon, nitrogen, aluminium, silicon, sulfur, titanium, nickel, copper, selenium, niobium, and molybdenum. Specific types of stainless steel are often designated by their AISI three-digit number, e.g., 304 stainless. The ISO 15510 standard lists the chemical compositions of stainless steels of the specifications in existing ISO, ASTM, EN, JIS, and GB standards in a useful interchange table.
A gas turbine, also called a combustion turbine, is a type of continuous and internal combustion engine. The main elements common to all gas turbine engines are:
Thorium dioxide (ThO2), also called thorium(IV) oxide, is a crystalline solid, often white or yellow in color. Also known as thoria, it is produced mainly as a by-product of lanthanide and uranium production. Thorianite is the name of the mineralogical form of thorium dioxide. It is moderately rare and crystallizes in an isometric system. The melting point of thorium oxide is 3300 °C – the highest of all known oxides. Only a few elements (including tungsten and carbon) and a few compounds (including tantalum carbide) have higher melting points. All thorium compounds are radioactive because there are no stable isotopes of thorium.
Inconel is a registered trademark of Special Metals Corporation for a family of austenitic nickel-chromium-based superalloys.
A superalloy, or high-performance alloy, is an alloy with the ability to operate at a high fraction of its melting point. Several key characteristics of a superalloy are excellent mechanical strength, resistance to thermal creep deformation, good surface stability, and resistance to corrosion or oxidation.
Austenitic stainless steel is one of the five classes of stainless steel by crystalline structure. Its primary crystalline structure is austenite and it prevents steels from being hardenable by heat treatment and makes them essentially non-magnetic. This structure is achieved by adding enough austenite stabilizing elements such as nickel, manganese and nitrogen.
Titanium aluminide, TiAl, commonly gamma titanium, is an intermetallic chemical compound. It is lightweight and resistant to oxidation and heat, but has low ductility. The density of γ-TiAl is about 4.0 g/cm3. It finds use in several applications including aircraft, jet engines, sporting equipment and automobiles. The development of TiAl based alloys began circa 1970. The alloys have been used in these applications only since about 2000.
The SAE steel grades system is a standard alloy numbering system for steel grades maintained by SAE International.
Exotic Materials can include plastics, superalloys, semiconductors, superconductors, and ceramics.
Alloy steel is steel that is alloyed with a variety of elements in total amounts between 1.0% and 50% by weight to improve its mechanical properties. Alloy steels are broken down into two groups: low alloy steels and high alloy steels. The difference between the two is disputed. Smith and Hashemi define the difference at 4.0%, while Degarmo, et al., define it at 8.0%. Most commonly, the phrase "alloy steel" refers to low-alloy steels.
An Aluminium alloy is an alloy in which aluminium (Al) is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon, tin and zinc. There are two principal classifications, namely casting alloys and wrought alloys, both of which are further subdivided into the categories heat-treatable and non-heat-treatable. About 85% of aluminium is used for wrought products, for example rolled plate, foils and extrusions. Cast aluminium alloys yield cost-effective products due to the low melting point, although they generally have lower tensile strengths than wrought alloys. The most important cast aluminium alloy system is Al–Si, where the high levels of silicon (4.0–13%) contribute to give good casting characteristics. Aluminium alloys are widely used in engineering structures and components where light weight or corrosion resistance is required.
Abdus Suttar Khan was a Bangladeshi scientist. He researched on aerospace for four decades with NASA, United Technology, and Alstom, a French power generation company. Khan invented more than forty different alloys for commercial application in space shuttles, jet engines, train engines and industrial gas turbines.
A turbine blade is the individual component which makes up the turbine section of a gas turbine or steam turbine. The blades are responsible for extracting energy from the high temperature, high pressure gas produced by the combustor. The turbine blades are often the limiting component of gas turbines. To survive in this difficult environment, turbine blades often use exotic materials like superalloys and many different methods of cooling that can be categorized as internal and external cooling, and thermal barrier coatings. Blade fatigue is a major source of failure in steam turbines and gas turbines. Fatigue is caused by the stress induced by vibration and resonance within the operating range of machinery. To protect blades from these high dynamic stresses, friction dampers are used.
Nimonic is a registered trademark of Special Metals Corporation that refers to a family of nickel-based high-temperature low creep superalloys. Nimonic alloys typically consist of more than 50% nickel and 20% chromium with additives such as titanium and aluminium.
The Hiduminium alloys or R.R. alloys are a series of high-strength, high-temperature aluminium alloys, developed for aircraft use by Rolls-Royce ("RR") before World War II. They were manufactured and later developed by High Duty Alloys Ltd. The name Hi-Du-Minium is derived from that of High Duty Aluminium Alloys.
Cobalt-chrome or cobalt-chromium (CoCr) is a metal alloy of cobalt and chromium. Cobalt-chrome has a very high specific strength and is commonly used in gas turbines, dental implants, and orthopedic implants.
Inconel Alloy 625 is a nickel-based superalloy that possesses high strength properties and resistance to elevated temperatures. It also demonstrates remarkable protection against corrosion and oxidation. Its ability to withstand high stress and a wide range of temperatures, both in and out of water, as well as being able to resist corrosion while being exposed to highly acidic environments makes it a fitting choice for nuclear and marine applications.
Havar, or UNS R30004, is an alloy of cobalt, possessing very a high mechanical strength. It can be heat-treated. It is highly resistant to corrosion and is non-magnetic. It is biocompatible. It has high fatigue resistance. It is a precipitation hardening superalloy.