Microstructural evolution and the variation of tensile behavior after aging heat treatment of precipitation hardened martensitic steel
| Autor: | Jong-Ho Shin, Jae-Suk Jeong, Jong-Wook Lee |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
Materials science
Strain (chemistry) Mechanical Engineering Metallurgy macromolecular substances Atmospheric temperature range Lath engineering.material Strain hardening exponent Plasticity Condensed Matter Physics Microstructure Precipitation hardening Materials Science(all) Mechanics of Materials Martensite engineering General Materials Science |
| Zdroj: | Materials Characterization. 99:230-237 |
| ISSN: | 1044-5803 |
| DOI: | 10.1016/j.matchar.2014.11.024 |
| Popis: | The effects of aging temperature on the microstructural evolution and the tensile behavior of precipitation hardened martensitic steel were investigated. Microscopic analysis using transmission electron microscope (TEM) was combined with the microstructural analysis using the synchrotron X-ray diffraction (XRD) to characterize the microstructural evolution with aging temperature. Peak hardness was obtained by precipitation of the Ni{sub 3}Al ordered phase. After aging at temperature range from 420 to 590 °C, spherical Ni{sub 3}Al precipitates and ellipsoidal M{sub 23}C{sub 6} carbides were observed within laths and at lath boundaries, respectively. Strain hardening behavior was analyzed with Ludwik equation. It is observed that the plastic strain regimes can be divided into two different stages by a rapid increase in strain hardening followed by a comparatively lower increase. At the first strain hardening stage, the aged specimen exhibited higher strain hardening exponent than the as-quenched specimen, and the exponent in the aged specimen was not changed considerably with increasing aging temperature. It is revealed that the strain hardening exponents at the first and the second stages were associated with the Ni{sub 3}Al precipitates and the domain size representing the coherent scattering area, respectively. - Highlights: • All of aged specimen exhibited higher strain hardeningmore » exponent than the as-quenched specimen at the first stage. • The value of strain hardening exponent in the aged specimen was nearly constant with aging temperature. • Ni{sub 3}Al precipitation dominantly influenced to the increase of strain hardening exponent at the first strain hardening stage. • Domain size was associated with strain hardening exponent at the second strain hardening stage.« less |
| Databáze: | OpenAIRE |
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