Abstract
The paper considers the physics of cold brittleness of structural bcc steels and methods of reducing the ductile-brittle fracture temperature. A complex study was performed to examine the degradation of structural phase state of pipe steel 09Mn2Si from the main gas pipeline of Yakutia after long-term (over 3 0 years) operation. Important regularities of degradation of pearlite colonies with carbide precipitation on ferrite grain boundaries were revealed. This phenomenon is associated with brittle fracture of gas pipelines. It is shown that the low-temperature kinetic processes in main pipelines which define the degradation of their structure and properties are related to interstitial athermal structural states in the zones of local crystal structure curvature. This is a fundamentally new, as yet unknown, mechanism. Pipe steels in warm rolling acquire a longitudinal textured band structure with alternating bands of initial ferrite grains and bands of fine grains with carbide precipitates formed during lamellar pearlite degradation. This type of structure allows for a shift of ductile-brittle transition temperature down to -80°C and ductility δ = 22% at this temperature. The production of high-curvature vortex structure in pipe steel surface layers results in a 3.5-fold increase in their service life.
| Original language | English |
|---|---|
| Pages (from-to) | 125-133 |
| Number of pages | 9 |
| Journal | Physical Mesomechanics |
| Volume | 20 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 1 Apr 2017 |
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Keywords
- athermal processes in zones of structure curvature
- cold brittleness
- cold-brittleness reduction methods
- crystal structure curvature
- low-temperature structural phase transitions
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Surfaces and Interfaces
Cite this
Scientific basis for cold brittleness of structural BCC steels and their structural degradation at below zero temperatures. / Panin, V. E.; Derevyagina, L. S.; Lebedev, M. P.; Syromyatnikova, A. S.; Surikova, N. S.; Pochivalov, Yu I.; Ovechkin, B. B.
In: Physical Mesomechanics, Vol. 20, No. 2, 01.04.2017, p. 125-133.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Scientific basis for cold brittleness of structural BCC steels and their structural degradation at below zero temperatures
AU - Panin, V. E.
AU - Derevyagina, L. S.
AU - Lebedev, M. P.
AU - Syromyatnikova, A. S.
AU - Surikova, N. S.
AU - Pochivalov, Yu I.
AU - Ovechkin, B. B.
PY - 2017/4/1
Y1 - 2017/4/1
N2 - The paper considers the physics of cold brittleness of structural bcc steels and methods of reducing the ductile-brittle fracture temperature. A complex study was performed to examine the degradation of structural phase state of pipe steel 09Mn2Si from the main gas pipeline of Yakutia after long-term (over 3 0 years) operation. Important regularities of degradation of pearlite colonies with carbide precipitation on ferrite grain boundaries were revealed. This phenomenon is associated with brittle fracture of gas pipelines. It is shown that the low-temperature kinetic processes in main pipelines which define the degradation of their structure and properties are related to interstitial athermal structural states in the zones of local crystal structure curvature. This is a fundamentally new, as yet unknown, mechanism. Pipe steels in warm rolling acquire a longitudinal textured band structure with alternating bands of initial ferrite grains and bands of fine grains with carbide precipitates formed during lamellar pearlite degradation. This type of structure allows for a shift of ductile-brittle transition temperature down to -80°C and ductility δ = 22% at this temperature. The production of high-curvature vortex structure in pipe steel surface layers results in a 3.5-fold increase in their service life.
AB - The paper considers the physics of cold brittleness of structural bcc steels and methods of reducing the ductile-brittle fracture temperature. A complex study was performed to examine the degradation of structural phase state of pipe steel 09Mn2Si from the main gas pipeline of Yakutia after long-term (over 3 0 years) operation. Important regularities of degradation of pearlite colonies with carbide precipitation on ferrite grain boundaries were revealed. This phenomenon is associated with brittle fracture of gas pipelines. It is shown that the low-temperature kinetic processes in main pipelines which define the degradation of their structure and properties are related to interstitial athermal structural states in the zones of local crystal structure curvature. This is a fundamentally new, as yet unknown, mechanism. Pipe steels in warm rolling acquire a longitudinal textured band structure with alternating bands of initial ferrite grains and bands of fine grains with carbide precipitates formed during lamellar pearlite degradation. This type of structure allows for a shift of ductile-brittle transition temperature down to -80°C and ductility δ = 22% at this temperature. The production of high-curvature vortex structure in pipe steel surface layers results in a 3.5-fold increase in their service life.
KW - athermal processes in zones of structure curvature
KW - cold brittleness
KW - cold-brittleness reduction methods
KW - crystal structure curvature
KW - low-temperature structural phase transitions
UR - http://www.scopus.com/inward/record.url?scp=85020023964&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85020023964&partnerID=8YFLogxK
U2 - 10.1134/S1029959917020023
DO - 10.1134/S1029959917020023
M3 - Article
VL - 20
SP - 125
EP - 133
JO - Physical Mesomechanics
JF - Physical Mesomechanics
SN - 1029-9599
IS - 2
ER -