Gamma-austenite

Heating iron to 907°C causes a change from BCC (alpha, ferrite) iron to the FCC (gamma, austenite) form. 

Gamma-austenite (y-austenite, fee). Austenite is a solid insertion solution of carbon into the crystal lattice of face-centered cubic gamma-iron. It has been definitively established that the carbon atoms in austenite occupy interstitial positions in the face-centered cubic space lattice causing the lattice parameter to increase progressively with the carbon content. 

Austenite Solid solution of carbon in gamma iron (fee), with up to about 8% of the available sites occupied by C atoms... 

GAMMA TO ALPHA TRANSFORMATION IN AUSTENITIC STAINLESS STEEL UNDER STRESS (SINGLE AND REPEATED) DOWN TO 20°K... 

The radionuclides of principal significance in contamination buildup, their origins and their production reactions are summarized in Table 4.2. These radionuclides are all gamma emitters with a comparatively long halflife. In virtually all plants, the radiation dose rates in the area surrounding the circuits and components are predominantly due to °Co, because of the high energies of its y quants of 1.17 and 1.33 MeV and the transition probability of both of them of 100%. Besides Co, additional activation products of other constituents of austenitic steels and nickel-based alloys, in particular Co, have to be mentioned. Only in special cases... 

Steels which contain both the body-centered cubic alpha-phase and the face-centered cubic gamma-phase, are called Duplex Steels. Austenitic ferritic steels containing about 5% or more delta-ferrite show a higher resistance than... 

For example, the formation of nonequilibrium y, y, and G phase have aU been observed in 316 stainless steels [32]. Both RIS and RIP are observed in the 250—300°C range in 300 series austenitic stainless steels. Due to enrichment of nickel and silicon at defect sinks, the G-phase sUicides are present after modest irradiation fluences [48]. In addition, many other types of phases have been observed in irradiated stainless steels, including carbides, Laves, and gamma [32]. The extent of precipitation and type of precipitates are extremely sensitive to the exact temperature, dose, and dose rate, but are also dependent on the specific damage microstructure. 

Stainless steel, austenitic (vacuum technology) A non-magnetic, non-dispersion-hardenable stainless steel composed mainly of austenite (gamma iron with carbon in solution), stabilized by nickel. See also Stainless steel, martinsitic. 

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