Irradiation-induced phase transformation in type 304 stainless steel

Abstract

Conversion electron Mössbauer spectroscopy has been used to study irradiation effects in the near surface region of type 304 stainless steel after 40 keV helium ion bombardment; a ferromagnetic phase in the paramagnetic matrix was observed after the irradiation to 8×1017 ion/cm2 at 200 °C. The amount of ferromagnetic phase was found to increase with increasing helium ion fluence.

Mechanism of FIB-Induced Phase Transformation in Austenitic Steel

“…An austenite to α′ martensite transformation was noted after implanting 316 stainless steel with 80 keV Sb + ions (Johnson et al, 1982). Observations of the austenite to α′ martensite phase transformation under 40 keV He + ion bombardment have also been reported (Hayashi & Takahashi, 1982; Hayashi et al, 1984). The extent of transformation increased as a function of dose, and the depth of the transformation was consistent with the light ion implantation range and depth from the sample surface (Hayashi et al, 1984; Sakamoto, et al, 1988, 1990).…”

“…The transformation from austenite to the BCC phase as a result of ion beam irradiation of austenitic stainless steels is clearly important and has been shown to occur independent of the ion or particle species (Hayashi & Takahashi, 1982; Johnson et al, 1982; Hayashi et al, 1988; Sakamoto et al, 1990; Gustiono et al, 2004). Ga + ion irradiation has been shown to transform the austenite in a super duplex stainless steel (Basa et al, 2014) and stainless steels (Knipling et al, 2010; Babu et al, 2016; Li & Liu, 2020).…”

Ion-induced Transformation of Metastable Phases

“…Several prior studies have reported on the observation of ion beam induced transformation of austenitic steels and other metastable austenitic phases bombarded with both light ions such as He + and a variety of heavy ions. In all cases, the transformation is consistent with and dependent on ion species, ion dose, channeling, angle of ion incidence, ion energy, and austenite stability [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19].…”

Surface composition and near-surface hardness studies on high dose boron-implanted 304 stainless steel

“…It has been observed that a 7ycc to ~,cc transformation is induced in austenitic stainless steels implanted with phosphorus, antimony or boron and the driving force for this transformation is the relief effected in the implanted layer experiencing high levels of stress caused by the accumulation of radiation damage (Johnson et al 1982(Johnson et al , 1985Raud et al 1989). This interpretation is supported by the observation of an ~'b~c phase in helium-implanted austenitic 304 stainless steel (Hayashi and Takahashi 1982;Hayashi et al 1984).…”