The Fe-Cr-C claddings formed by arc surface welding with different La2O3 additions were investigated. The microstructures were observed by optical microscopy （OM）, field emission scanning electron microscopy （FESEM...The Fe-Cr-C claddings formed by arc surface welding with different La2O3 additions were investigated. The microstructures were observed by optical microscopy （OM）, field emission scanning electron microscopy （FESEM） and transmission electron microscopy （TEM）. The phase structures were measured by X-ray diffraction （XRD）. The wear resistances of the claddings were tested by friction and wear ex- periment. On this basis, the carbide refinement mechanism by inclusion enriched with La was discussed theoretically. The results showed that, the microsttucture of the Fe-Cr-C cladding consisted of primary （Cr, Fe）TC3 carbides and eutectic （γ-Fe＋（Cr, Fe）7C3） structure. With La2O3 ad- dition increasing, the primary carbides were refined, and the mass loss of the cladding decreased gradually. The Fe-Cr-C cladding with 4 wt.% La2O3 addition had a best wear resistance behaviour. The RE inclusion LaAlO3 as heterogeneous nuclei of the primary MTC3 was medium ef- fective, and could refine the M7C3 carbides. Besides, the wear resistance could be improved by adding La2O3 in the claddings.展开更多
基金Project supported by National Natural Science Foundation of China(51271163)Key Project of Science and Technology of Hebei Province(09215106D)
文摘The Fe-Cr-C claddings formed by arc surface welding with different La2O3 additions were investigated. The microstructures were observed by optical microscopy （OM）, field emission scanning electron microscopy （FESEM） and transmission electron microscopy （TEM）. The phase structures were measured by X-ray diffraction （XRD）. The wear resistances of the claddings were tested by friction and wear ex- periment. On this basis, the carbide refinement mechanism by inclusion enriched with La was discussed theoretically. The results showed that, the microsttucture of the Fe-Cr-C cladding consisted of primary （Cr, Fe）TC3 carbides and eutectic （γ-Fe＋（Cr, Fe）7C3） structure. With La2O3 ad- dition increasing, the primary carbides were refined, and the mass loss of the cladding decreased gradually. The Fe-Cr-C cladding with 4 wt.% La2O3 addition had a best wear resistance behaviour. The RE inclusion LaAlO3 as heterogeneous nuclei of the primary MTC3 was medium ef- fective, and could refine the M7C3 carbides. Besides, the wear resistance could be improved by adding La2O3 in the claddings.
