Abstract
In the work, we studied structural phase states in surface layers of electron beam-irradiated nickel-titanium (NiTi) alloy depending on beam energy density. The surface of NiTi specimens was exposed to pulsed irradiation (pulse duration τ = 150 μs, number of pulses N = 5) by a low-energy high-current (I = 70 A) electron beam with surface melting at electron beam energy densities E1 = 15 J/cm2, E2 = 20 J/cm2, and E3 = 30 J/cm2. The surface layer structure was examined by X-ray diffraction analysis and transmission electron microscopy. It is found that in the NiTi specimens irradiated at E ≤ 20 J/cm the layer that contains a martensite phase resides not on the surface but at some depth from it. In the NiTi specimens irradiated at E = 30 J/cm, the entire modified surface zone is characterized by a two-phase state in which the B19′ phase dominates over the B2 phase. It is supposed that a barrier to B2 → B19′ martensite transformation in the melted NiTi layer irradiated at E ≤ 20 J/cm2 is high inhomogeneous residual stresses varying with depth from the irradiated surface.
| Original language | English |
|---|---|
| Pages (from-to) | 44-52 |
| Number of pages | 9 |
| Journal | Applied Surface Science |
| Volume | 324 |
| DOIs | |
| Publication status | Published - 1 Jan 2015 |
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Keywords
- B19′ martensite phase
- B2 phase
- Low-energy high-current electron beams
- Nickel-titanium alloy
- Structural phase states
- X-ray diffraction analysis
ASJC Scopus subject areas
- Surfaces, Coatings and Films
Cite this
Surface microstructure and B2 phase structural state induced in NiTi alloy by a high-current pulsed electron beam. / Meisner, L. L.; Ostapenko, M. G.; Lotkov, A. I.; Neiman, A. A.
In: Applied Surface Science, Vol. 324, 01.01.2015, p. 44-52.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Surface microstructure and B2 phase structural state induced in NiTi alloy by a high-current pulsed electron beam
AU - Meisner, L. L.
AU - Ostapenko, M. G.
AU - Lotkov, A. I.
AU - Neiman, A. A.
PY - 2015/1/1
Y1 - 2015/1/1
N2 - In the work, we studied structural phase states in surface layers of electron beam-irradiated nickel-titanium (NiTi) alloy depending on beam energy density. The surface of NiTi specimens was exposed to pulsed irradiation (pulse duration τ = 150 μs, number of pulses N = 5) by a low-energy high-current (I = 70 A) electron beam with surface melting at electron beam energy densities E1 = 15 J/cm2, E2 = 20 J/cm2, and E3 = 30 J/cm2. The surface layer structure was examined by X-ray diffraction analysis and transmission electron microscopy. It is found that in the NiTi specimens irradiated at E ≤ 20 J/cm the layer that contains a martensite phase resides not on the surface but at some depth from it. In the NiTi specimens irradiated at E = 30 J/cm, the entire modified surface zone is characterized by a two-phase state in which the B19′ phase dominates over the B2 phase. It is supposed that a barrier to B2 → B19′ martensite transformation in the melted NiTi layer irradiated at E ≤ 20 J/cm2 is high inhomogeneous residual stresses varying with depth from the irradiated surface.
AB - In the work, we studied structural phase states in surface layers of electron beam-irradiated nickel-titanium (NiTi) alloy depending on beam energy density. The surface of NiTi specimens was exposed to pulsed irradiation (pulse duration τ = 150 μs, number of pulses N = 5) by a low-energy high-current (I = 70 A) electron beam with surface melting at electron beam energy densities E1 = 15 J/cm2, E2 = 20 J/cm2, and E3 = 30 J/cm2. The surface layer structure was examined by X-ray diffraction analysis and transmission electron microscopy. It is found that in the NiTi specimens irradiated at E ≤ 20 J/cm the layer that contains a martensite phase resides not on the surface but at some depth from it. In the NiTi specimens irradiated at E = 30 J/cm, the entire modified surface zone is characterized by a two-phase state in which the B19′ phase dominates over the B2 phase. It is supposed that a barrier to B2 → B19′ martensite transformation in the melted NiTi layer irradiated at E ≤ 20 J/cm2 is high inhomogeneous residual stresses varying with depth from the irradiated surface.
KW - B19′ martensite phase
KW - B2 phase
KW - Low-energy high-current electron beams
KW - Nickel-titanium alloy
KW - Structural phase states
KW - X-ray diffraction analysis
UR - http://www.scopus.com/inward/record.url?scp=84920656990&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84920656990&partnerID=8YFLogxK
U2 - 10.1016/j.apsusc.2014.10.124
DO - 10.1016/j.apsusc.2014.10.124
M3 - Article
AN - SCOPUS:84920656990
VL - 324
SP - 44
EP - 52
JO - Applied Surface Science
JF - Applied Surface Science
SN - 0169-4332
ER -