Fe-Mn Alloys for Cryogenic Use: A Brief Survey of Current Research

Abstract

The desire to minimize the nickel content of steels intended for service in cryogenic systems had led to research on the applicability of iron manganese alloys at 101-/ temperatures. In this paper the relevant physical metallurgy of the Fe-t'ln system is revie. .. •:ed and cryogenic alloy development. .

Interpretation of cryogenic-temperature Charpy impact toughness by microstructural evolution of dynamically compressed specimens in austenitic 0.4C–(22–26)Mn steels

“…Aluminum alloys have been conventionally used for cryogenic applications, but their applications are limited because of their relatively low toughness. In large-scale plants or vessels, Al alloys have been replaced by high-Ni-based invar alloys or austenitic stainless steels [8][9][10][11]. Ni, a typical austenite stabilizer, is very expensive (about ten times more expensive than any other alloying element of austenitic stainless steels) because the extraction of Ni from Ni ores containing Cu needs many complicated processing steps [12][13][14].…”

“…Recently, efforts have been made to replace expensive austenitic stainless steels with more reasonably priced high-Mn steels which are comparable to austenitic stainless steels in terms of strength, ductility and toughness. Given the economic cost of ecofriendliness, the area in which high-Mn steels find the greatest application is the mass production of high-quality steels requiring reasonable strength and toughness levels [8][9][10][15][16][17].…”

Interpretation of cryogenic-temperature Charpy fracture initiation and propagation energies by microstructural evolution occurring during dynamic compressive test of austenitic Fe–(0.4,1.0)C–18Mn steels

“…This is because ε-martensites are not formed even at À 196°C ( Fig. 8(f)), and because the Charpy toughness follows a general trend of decreasing toughness with decreasing temperature in fcc materials [3,[31][32][33]. The E P of the 10C steel reaches 64 J at À 196°C, unlike the 4C steel (29 J), thereby resulting in the high E T (124 J).…”

“…For example, the storage or transportation of liquefied natural gas is globally demanded, and thus austenitic high-Mn steels have been actively developed for cryogenic applications. Fcc metals are widely used because of their sufficient low-temperature toughness, whereas bcc metals show the ductile-brittle transition [1][2][3][4]. Austenitic stainless steels, 9% Ni alloys, or Ni-based Invar alloys are generally used in large-scale plants or industries, but many efforts have been directed towards replacing these expensive alloys to inexpensive high-Mn steels whose strength, ductility, and toughness are comparable.…”

“…Efforts have also been made to achieve an excellent combination of high strength and toughness by using deformation mechanisms [1][2][3][4][5][6][7][8][9]. These mechanisms are mainly changed by stacking fault energy (SFE), and the SFE generally increases with increasing C and Mn contents [5][6][7][8][9][10][11][12][13][14].…”