| Автор | G Das |
| Автор | V Rao |
| Автор | A Joarder |
| Автор | O N Mohanty |
| Автор | S G N Murthy |
| Автор | A Mitra |
| Дата выпуска | 1995-11-14 |
| dc.description | The magnetic properties of a process heater tube were determined to evaluate the structural integrity of its use in the oil industry. Carbon diffusion inside the tube during processing of petroleum is a cause of concern in the oil industry because it leads to brittle fracture. Both magnetic hysteresis and magneto-acoustic emission (MAE) parameters were determined for three specimens made from virgin, laboratory-aged and service-exposed materials. It was expected that the coercivity would be a good damage parameter by which to assess the service-exposed material because it increased with carbon concentration. However, the observed insignificant difference in coercivity between service-exposed material and the virgin one ruled out the possibility of using coercivity as a suitable damage parameter. The present study indicated that saturation induction could be used to find the extent of carbon deposition inside the material. The RMS voltage (V<sub>rms</sub>) of the MAE signal signal at low field was found to be higher in the laboratory-aged specimen due to greater interparticle distances which allowed domain walls to move longer distances before encountering a pinning centre. At high field, V<sub>rms</sub> in the virgin specimen was found to be higher than that in laboratory-aged and service-exposed materials. That was attributed to the presence of higher anisotropy in the virgin sample, originating from the metallurgical processing. |
| Формат | application.pdf |
| Издатель | Institute of Physics Publishing |
| Название | Magnetic characterization of 5Cr-0.5Mo steel used in process heater tubes |
| Тип | paper |
| DOI | 10.1088/0022-3727/28/11/002 |
| Electronic ISSN | 1361-6463 |
| Print ISSN | 0022-3727 |
| Журнал | Journal of Physics D: Applied Physics |
| Том | 28 |
| Первая страница | 2229 |
| Последняя страница | 2234 |
| Аффилиация | G Das; Nat. Metall. Lab., Jamshedpur, India |
| Аффилиация | V Rao; Nat. Metall. Lab., Jamshedpur, India |
| Аффилиация | A Joarder; Nat. Metall. Lab., Jamshedpur, India |
| Аффилиация | O N Mohanty; Nat. Metall. Lab., Jamshedpur, India |
| Аффилиация | S G N Murthy; Nat. Metall. Lab., Jamshedpur, India |
| Аффилиация | A Mitra; Nat. Metall. Lab., Jamshedpur, India |
| Выпуск | 11 |
