Structures and Mechanical Properties of Some Dual-Phase Steels with Low Manganese Content
In recent years, to reduce cars costs, research has been conducted on dual-phase steels with low manganese content (below 1.0%). This study investigated the influence of technological parameters of heat treatment (heating temperature and cooling medium) on such steels’ structures and mechanical prop...
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MDPI AG
2022-01-01
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| Series: | Metals |
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| Online Access: | https://www.mdpi.com/2075-4701/12/2/189 |
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| author | Constantin Dulucheanu Traian Lucian Severin Delia Aurora Cerlinca Luminita Irimescu |
| author_facet | Constantin Dulucheanu Traian Lucian Severin Delia Aurora Cerlinca Luminita Irimescu |
| author_sort | Constantin Dulucheanu |
| collection | DOAJ |
| description | In recent years, to reduce cars costs, research has been conducted on dual-phase steels with low manganese content (below 1.0%). This study investigated the influence of technological parameters of heat treatment (heating temperature and cooling medium) on such steels’ structures and mechanical properties. The ferrite-martensitic structures, specific for dual-phase steels, were obtained by intercritical quenching: heating of samples (made of alloys with 0.511% Mn, respectively 0.529% Mn) to temperatures located between critical points Ac<sub>1</sub> and Ac<sub>3</sub>, followed by cooling in water without mechanical agitation and in water activated with ultrasounds at the frequency of 59 kHz. Through metallographic analyses and tensile tests, it was possible to determine the volume fraction of martensite, the ferrite microhardness, the ultimate tensile strength, the total elongation, and with the obtained data, their variations with the heating temperature and the cooling medium were established. Raising the heating temperature (between 760 °C and 820 °C) and using ultrasounds at cooling increased the volume fraction of martensite and the ferrite microhardness. This fact has increased the mechanical strength and reduced the deformability of the studied dual-phase steels. Intercritical quenching in water activated with ultrasounds provided values of structural characteristics and mechanical properties very close to those obtained by quenching in water without mechanical agitation, but was accomplished using a higher-temperature heating. The results obtained were compared with those determined in previous research, performed on dual-phase steel with 1.90% Mn. |
| first_indexed | 2024-03-09T21:26:17Z |
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| issn | 2075-4701 |
| language | English |
| last_indexed | 2024-03-09T21:26:17Z |
| publishDate | 2022-01-01 |
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| spelling | doaj.art-16a9f9b0a2134c70b71bc0ecd9a196d32023-11-23T21:06:22ZengMDPI AGMetals2075-47012022-01-0112218910.3390/met12020189Structures and Mechanical Properties of Some Dual-Phase Steels with Low Manganese ContentConstantin Dulucheanu0Traian Lucian Severin1Delia Aurora Cerlinca2Luminita Irimescu3Faculty of Mechanical Engineering, Automotive and Robotics, “Stefan cel Mare” University of Suceava, 13 University Street, 720229 Suceava, RomaniaFaculty of Mechanical Engineering, Automotive and Robotics, “Stefan cel Mare” University of Suceava, 13 University Street, 720229 Suceava, RomaniaFaculty of Mechanical Engineering, Automotive and Robotics, “Stefan cel Mare” University of Suceava, 13 University Street, 720229 Suceava, RomaniaFaculty of Mechanical Engineering, Automotive and Robotics, “Stefan cel Mare” University of Suceava, 13 University Street, 720229 Suceava, RomaniaIn recent years, to reduce cars costs, research has been conducted on dual-phase steels with low manganese content (below 1.0%). This study investigated the influence of technological parameters of heat treatment (heating temperature and cooling medium) on such steels’ structures and mechanical properties. The ferrite-martensitic structures, specific for dual-phase steels, were obtained by intercritical quenching: heating of samples (made of alloys with 0.511% Mn, respectively 0.529% Mn) to temperatures located between critical points Ac<sub>1</sub> and Ac<sub>3</sub>, followed by cooling in water without mechanical agitation and in water activated with ultrasounds at the frequency of 59 kHz. Through metallographic analyses and tensile tests, it was possible to determine the volume fraction of martensite, the ferrite microhardness, the ultimate tensile strength, the total elongation, and with the obtained data, their variations with the heating temperature and the cooling medium were established. Raising the heating temperature (between 760 °C and 820 °C) and using ultrasounds at cooling increased the volume fraction of martensite and the ferrite microhardness. This fact has increased the mechanical strength and reduced the deformability of the studied dual-phase steels. Intercritical quenching in water activated with ultrasounds provided values of structural characteristics and mechanical properties very close to those obtained by quenching in water without mechanical agitation, but was accomplished using a higher-temperature heating. The results obtained were compared with those determined in previous research, performed on dual-phase steel with 1.90% Mn.https://www.mdpi.com/2075-4701/12/2/189dual-phase steellow manganese contentintercritical quenchingultrasoundsferritemartensite |
| spellingShingle | Constantin Dulucheanu Traian Lucian Severin Delia Aurora Cerlinca Luminita Irimescu Structures and Mechanical Properties of Some Dual-Phase Steels with Low Manganese Content Metals dual-phase steel low manganese content intercritical quenching ultrasounds ferrite martensite |
| title | Structures and Mechanical Properties of Some Dual-Phase Steels with Low Manganese Content |
| title_full | Structures and Mechanical Properties of Some Dual-Phase Steels with Low Manganese Content |
| title_fullStr | Structures and Mechanical Properties of Some Dual-Phase Steels with Low Manganese Content |
| title_full_unstemmed | Structures and Mechanical Properties of Some Dual-Phase Steels with Low Manganese Content |
| title_short | Structures and Mechanical Properties of Some Dual-Phase Steels with Low Manganese Content |
| title_sort | structures and mechanical properties of some dual phase steels with low manganese content |
| topic | dual-phase steel low manganese content intercritical quenching ultrasounds ferrite martensite |
| url | https://www.mdpi.com/2075-4701/12/2/189 |
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