Nickel base superalloys

The highly aHoyed austenitic stainless steels are proprietary modifications of the standard AISI 316 stainless steel. These have higher creep—mpture strengths than the standard steels, yet retain the good corrosion resistance and forming characteristics of the standard austenitic stainless steels. Nickel-Base Superalloys. [Pg.119]

Table 4. Chemical Composition of Wrought and Powder Nickel-Base Superalloys, wt %...

Appllca.tlons. The principal appHcations of nickel-base superalloys are in gas turbines, where they are utilized as blades, disks, and sheet metal parts. Abcraft gas turbines utilized in both commercial and military service depend upon superalloys for parts exposed to peak metal temperatures in excess of 1000°C. Typical gas turbine engines produced in the United States in 1990 utilized nickel and cobalt-base superalloys for 46% of total engine weight (41). However, programs for future aerospace propulsion systems emphasize the need for lightweight materials having greater heat resistance. For such apphcations, intermetallics matrix composites and ceramic composites are expected to be needed. [Pg.123]

Using rapid solidification technology molten metal is quench cast at a cooling rate up to 10 °C/s as a continuous ribbon. This ribbon is subsequently pulverized to an amorphous powder. RST powders include aluminum alloys, nickel-based superalloys, and nanoscale powders. RST conditions can also exist in powder atomization. [Pg.182]

Because of constitutional complexity, the exact chemistries of nickel-base superalloys must be controlled carehiUy in order to avoid the precipitation of deleterious topologically close-packed (TCP) phases and extraneous carbides after long-term high temperature exposure. Heat-treatment schedules and thermomechanical treatments in the case of wrought alloys also are important to provide optimum strength and performance. [Pg.7]

Nickel and its alloys form another important class of non-ferrous metals (Table 1.3). The superb creep resistance of the nickel-based superalloys is a key factor in designing the modern gas-turbine aero-engine. But nickel alloys even appear in a model steam engine. The flat plates in the firebox must be stayed together to resist the internal steam pressure (see Fig. 1.3). Some model-builders make these stays from pieces of monel rod because it is much stronger than copper, takes threads much better and is very corrosion resistant. [Pg.7]

Until the late 1990s, Waspaloy was still the best alloy available for the majority of hot gas turboexpanders used in industry and, until recently, it continued to offer the many special characteristic needed for hot gas expander applications. However, a new development followed in 2000 when the Ebara Corporation (Japan) released data on a nickel-base superalloy. [Pg.242]

Sulfidation-Resistant Nickel-Base Superalloy for FCC Flue Gas Expanders... [Pg.242]

Early work on the fatigue strength of various metallic alloys including steels, aluminium alloys, copper alloys and nickel-base superalloys in vacuum and in air clearly demonstrated that fatigue performance improved in... [Pg.1313]

Detailed consideration of the structure of many of the advanced and complex alloys which are of considerable technological importance (high-strength titanium alloys, nickel-base superalloys, etc.) is beyond the scope of this section, other than to point out that no new principles are involved. Certain titanium alloys, for example, exhibit a martensitic transformation, while many nickel-base superalloys are age hardening. Similarly, cast irons, although by no means advanced materials, are relatively complex they are considered in Section 1.3 where graphitisation is discussed. [Pg.1291]

Nickel barium titanium primrose priderite, formula and DCMA number, 7 347t Nickel-based alloys, properties of, 77 848t Nickel-base superalloys, 77 103 Nickel battery technology, 77 111 Nickel-beryllium alloys, 3 656-659 Nickel-boron deposition, 9 693-695, 708 Nickel brass, corrosion, 7 812 Nickel bromide, 77 110... [Pg.619]

This process, originally designated as RSR (rapid solidification rate), was developed by Pratt and Whitney Aircraft Group and first operated in the late 1975 for the production of rapidly solidified nickel-base superalloy powders.[185][186] The major objective of the process is to achieve extremely high cooling rates in the atomized droplets via convective cooling in helium gas jets (dynamic helium quenching effects). Over the past decade, this technique has also been applied to the production of specialty aluminum alloy, steel, copper alloy, beryllium alloy, molybdenum, titanium alloy and sili-cide powders. The reactive metals (molybdenum and titanium) and... [Pg.101]

Hafnium is obtained as a by-product of the production of hafnium-free nuclear-grade zirconium (see Nuclear reactors ZlRCONlUMAND zirconium compounds). Hafnium s primary use is as a minor strengthening agent in high temperature nickel-base superalloys. Additionally, hafnium is used as a neutron-absorber material, primarily in the form of control rods in nuclear reactors. [Pg.439]

J.K. Tien and S.M. Copley. The effect of uniaxial stress on the periodic morphology of coherent gamma prime precipitates in nickel-base superalloy crystals. Metall. Trans., 2 (1) 215—219, 1971. [Pg.383]

S.M. Allen and J.C. Chang. Elastic energy changes accompanying the gamma-prime rafting in nickel-base superalloys. J. Mater. Res., 6(9) 1843—1855, 1991. [Pg.383]

Iron-niekcl base superalloys were developed primarily from the stainless steels. In the United Slates, these alloys included 19-9 DL. lb-25-6, and A-286, Luler, higher nickel contents were employed to take advantage of the superior oxidation resistance of nickel and the beneficial effects of y -forming elements. All iron-nickel base superalloys rely on solid solution hardening lo some extent. [Pg.776]

A nickel-base superalloy having special utility in the production of single crystal gas turbine engine blades consisting essentially of about 1 to 3 percent rhenium, about 14 percent chromium, about 9.5% cobalt, about 3.8% tungsten, about 2 percent tantalum, about 1.5% molybdenum, about 0.05% carbon, about 0.004% boron and respectively, from about 3 to 4.8% aluminum, from about 4.8% to about 3 percent titanium, and balance substantially nickel. [Pg.263]

M.M. Shenoy et al Modeling effects of nonmetallic inclusions on LCF in DS nickel-base superalloys. Int. J. Fatigue 27, 113-127 (2005)... [Pg.128]

Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...