Notch fatigue behaviour of low-temperature gaseous carburised 316L austenitic stainless steel

In the present investigation, low temperature nitriding has been attempted on AISI 316L austenitic stainless steel by using a laboratory fluidized bed furnace. The nitriding was performed in temperature range between 400°C and 500°C. X-ray diffraction, metallography, and corrosion tests were used to characterize the resultant nitrided surface and layers. The results showed that fluidized bed process can be used to produce a precipitation-free nitrided layer characterized by the S phase or expanded austenite on austenitic stainless steel at temperatures below 500°C. But there exists a critical temperature and an incubation time for effective nitriding, below which nitriding is ineffective. The corrosion behaviour of the as-nitrided surfaces is significantly different from that previously reported for low temperature plasma nitriding. This anomaly is explained by the formation of iron oxide products and surface contamination during the fluidized process.

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The Effect of Surface Finish on Low-Temperature Acetylene-Based Carburization of 316L Austenitic Stainless Steel

Metallurgical and Materials Transactions B ◽

10.1007/s11663-014-0141-9 ◽

2014 ◽

Vol 45 (6) ◽

pp. 2338-2345 ◽

Cited By ~ 4

Author(s):

Yindong Ge ◽

Frank Ernst ◽

Harold Kahn ◽

Arthur H. Heuer

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Low Temperature ◽

Surface Finish ◽

316L Austenitic Stainless Steel ◽

Effect Of Surface

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Influence of Plastic Pre-Strain on Low-Temperature Gas Carburization of 316L Austenitic Stainless Steel

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.853.178 ◽

2016 ◽

Vol 853 ◽

pp. 178-183 ◽

Cited By ~ 3

Author(s):

Ya Wei Peng ◽

Jian Ming Gong ◽

Yong Jiang ◽

Ming Hui Fu ◽

Dong Song Rong

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Austenitic Stainless Steel ◽

Low Temperature ◽

Dislocation Density ◽

Carbon Diffusion ◽

Uniaxial Tensile ◽

Engineering Strain ◽

X Ray ◽

316L Austenitic Stainless Steel

In this paper, the influence of pre-strain on low-temperature gas carburization of 316L austenitic stainless steel was investigated. A group of flat specimens were uniaxial tensile to several levels of pre-strain including 5%, 10%, 15%, 20% and 25% engineering strain. Then, the pre-strained specimens was treated by low-temperature gas carburization at 470 °C for 30 h. In order to elucidate the effect of pre-strain on low-temperature gas carburization, optical microscopy (OM), X-ray diffractometer (XRD), scanning electron probe micro-analyzer (EPMA), microhardness tester and residual stress analyzer were used. Meanwhile, dislocation density of the pre-strained specimens was semi-quantitatively measured by means of X-ray diffraction analysis and the role of dislocation density on carbon diffusion during low-temperature gas carburization was discussed. The results show as follow: (1) the thicknesses of the carburized layers are independent of the pre-strain degree. (2) dislocation density increases with the increasing pre-strain, but almost has no effect on carbon diffusion at the given carburizing temperature. (3) an outstanding surface with hardness (≈ 1150 HV0.1) and compressive residual stress (≈1900 MPa) is introduced by low-temperature gas carburization, and the strengthening results of carburization are unaffected by pre-strain.

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