دورية أكاديمية
Surface Substructure and Properties of ZrB2p/6061Al Composite Treated by Laser Surface Melting under Extreme Cooling Conditions
| العنوان: | Surface Substructure and Properties of ZrB2p/6061Al Composite Treated by Laser Surface Melting under Extreme Cooling Conditions |
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| المؤلفون: | Zeng Yida, Chao Yuhjin, Luo Zhen, Huang Yongxian, Cai Yangchuan, Deng Lingzhu, Guo Weijia, Lei Yuchen, Lu Tong, Wang Zihao |
| المصدر: | High Temperature Materials and Processes, Vol 36, Iss 1, Pp 69-77 (2017) |
| بيانات النشر: | De Gruyter, 2017. |
| سنة النشر: | 2017 |
| المجموعة: | LCC:Technology LCC:Chemical technology LCC:Chemicals: Manufacture, use, etc. |
| مصطلحات موضوعية: | laser melting, zrb2p/6061al composite, finer distribution, thermal mismatch stress, Technology, Chemical technology, TP1-1185, Chemicals: Manufacture, use, etc., TP200-248 |
| الوصف: | Particulate reinforcement composite ZrB2p/6061Al was fabricated from Al-K2ZrF6-KBF4 by a direct melt reaction. Laser surface melting was used to improve the surface strength of the in situ ZrB2p/6061Al composite, which includes a series of laser-melted composites with different laser power and cooling conditions processed by a 2-kW yttrium aluminum garnet laser generator. The surface substructure of these laser-treated specimens was investigated by light optical microscopy, scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffractometry and transmission electron microscopy. The penetration depth of the molten pool increases with increases in power density, and decreases with increases in the degree of undercooling. The Vickers hardness of the laser-melted composites reached 60–75.2 HV in liquid nitrogen and 56–64.0 HV in air, and increased by 50.4 % and 28 %. Grain refinement with decreased cellular spacing is important in strength performance. Because of a thermocapillary flow vortex and α-Al phase precipitation, nano-ZrB2 particles were distributed along the cellular dendrite boundary as observed by scanning electron microscopy. This was considered to be a key factor responsible for the improved mechanical composite properties. When cooling under liquid nitrogen, the thermal mismatch stress between particles and the matrix generates a high dislocation density. The dislocation grows along the interface between the matrix and particles and provides the laser-melted composites with additional strength. |
| نوع الوثيقة: | article |
| وصف الملف: | electronic resource |
| اللغة: | English |
| تدمد: | 0334-6455 2191-0324 |
| Relation: | https://doaj.org/toc/0334-6455; https://doaj.org/toc/2191-0324 |
| DOI: | 10.1515/htmp-2015-0069 |
| URL الوصول: | https://doaj.org/article/3cb45e8da661463da7efb5b7ddd68282 |
| رقم الأكسشن: | edsdoj.3cb45e8da661463da7efb5b7ddd68282 |
| قاعدة البيانات: | Directory of Open Access Journals |
| تدمد: | 03346455 21910324 |
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| DOI: | 10.1515/htmp-2015-0069 |