A kind of Al-TiB2/TiC in situ composite with a homogenous microstructure was successfully prepared through in situ reaction of pure Ti and Al-B-C alloy with molten aluminum.In order to improve the distribution of the ...A kind of Al-TiB2/TiC in situ composite with a homogenous microstructure was successfully prepared through in situ reaction of pure Ti and Al-B-C alloy with molten aluminum.In order to improve the distribution of the particles and mechanical properties of the composites,subsequent hot rolling with increasing reduction was carried out.The microstructure evolution of the composites was characterized using field emission scanning electron microscopy(FESEM)and the mechanical properties were studied through tensile tests and microhardness measurement.It is found that both the microstructure uniformity and mechanical properties of the composites are significantly improved with increasing rolling reduction.The ultimate tensile strength and microhardness of the composites with90%rolling reduction reach185.9MPa and HV59.8,respectively,140%and35%higher than those of as-cast ones.Furthermore,the strengthening mechanism of the composite was analyzed based on the fracture morphologies.展开更多
The Fe-based alloy coatings reinforced with in situ synthesized TiB2-TiC were prepared on Q235 steel by reactive plasma cladding using Fe901 alloy, Ti, B4C, and graphite （C） powders us raw materials. The effects of ...The Fe-based alloy coatings reinforced with in situ synthesized TiB2-TiC were prepared on Q235 steel by reactive plasma cladding using Fe901 alloy, Ti, B4C, and graphite （C） powders us raw materials. The effects of C/B4C weight percentage ratio （0 - 1. 38 ） on the microstructure , microhardness , and wet sand abrasion resistance of the coatings were investigated. The results show that the coatings consist of （ Fe, Cr ） solid solution, TiC, TiB2, Ti8C5 , and Fe3 C phases. The decrease of C/B4 C ratio is propitious to the formation of TiB2 and Tis C5. Increasing the C/B4 C ratio can help to refine the microstructure of the coatings. However, the microhardness of the middle-upper of the coatings and the wet sand abrasion resistance of the coatings degenerate with the increase of C/B4C ratio. The coating exhibits the best wet sand abrasion resistance at C/BaC =0 and its average mass loss rate per unit wear distance is 0. 001 2%/m. The change of the wet sand abrasion resistance of the coatings with the C/B4C ratio can be mainly attributed to the combined action of the changes of microhardness and the volume percentage of the ceramic reinforcements containing titanium in the coatings.展开更多
基金Project(51501092)supported by the National Natural Science Foundation of ChinaProject(30915011332)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(2014M550292)supported by China Postdoctoral Science Foundation
文摘A kind of Al-TiB2/TiC in situ composite with a homogenous microstructure was successfully prepared through in situ reaction of pure Ti and Al-B-C alloy with molten aluminum.In order to improve the distribution of the particles and mechanical properties of the composites,subsequent hot rolling with increasing reduction was carried out.The microstructure evolution of the composites was characterized using field emission scanning electron microscopy(FESEM)and the mechanical properties were studied through tensile tests and microhardness measurement.It is found that both the microstructure uniformity and mechanical properties of the composites are significantly improved with increasing rolling reduction.The ultimate tensile strength and microhardness of the composites with90%rolling reduction reach185.9MPa and HV59.8,respectively,140%and35%higher than those of as-cast ones.Furthermore,the strengthening mechanism of the composite was analyzed based on the fracture morphologies.
基金This work is supported by the National Natural Science Foundation of China （Grant No. 51101051 ）, the Natural Science Foundation of Jiangsu Province （Grant No. BK2011250）, and Jiangsu Planned Projects for Postdoctoral Research Funds （Grant No. 1101017 C）.
文摘The Fe-based alloy coatings reinforced with in situ synthesized TiB2-TiC were prepared on Q235 steel by reactive plasma cladding using Fe901 alloy, Ti, B4C, and graphite （C） powders us raw materials. The effects of C/B4C weight percentage ratio （0 - 1. 38 ） on the microstructure , microhardness , and wet sand abrasion resistance of the coatings were investigated. The results show that the coatings consist of （ Fe, Cr ） solid solution, TiC, TiB2, Ti8C5 , and Fe3 C phases. The decrease of C/B4 C ratio is propitious to the formation of TiB2 and Tis C5. Increasing the C/B4 C ratio can help to refine the microstructure of the coatings. However, the microhardness of the middle-upper of the coatings and the wet sand abrasion resistance of the coatings degenerate with the increase of C/B4C ratio. The coating exhibits the best wet sand abrasion resistance at C/BaC =0 and its average mass loss rate per unit wear distance is 0. 001 2%/m. The change of the wet sand abrasion resistance of the coatings with the C/B4C ratio can be mainly attributed to the combined action of the changes of microhardness and the volume percentage of the ceramic reinforcements containing titanium in the coatings.
