Ceramics-Silikáty 62, (1) 74 - 80 (2018)

By adding Na₂B₄O₇ into the Al-Fe₂O₃-Cr₂O₃ reaction system, the Al₂O₃ ceramic-lined steel pipe was prepared with the gravitational separation SHS method, and the influence of the Na₂B₄O₇ addition on the structure and properties of the produced composite steel pipe was investigated. The obtained results showed that the phase composition of the ceramic coating was Al₂O₃-FeCr Alloy-(Al_0.9Cr_0.1)₂O₃ composite, and with the increase of the amount of Na₂B₄O₇ addition, the Fe-Cr alloy particles left in the ceramic coating increased and distributed uniformly, and the denser ceramic coating was obtained. However, when the amount of Na₂B₄O₇ addition increased further to over 4%, the ceramic coating became fractures, the hardness of ceramic coating decreased. The transition structure of steel pipe-transition layer-ceramic coating was formed, the thickness of the transition layer decreased with the addition of Na₂B₄O₇, and the boundaries between the transition layer and the ceramic layer were less obvious, which would have a significant effect on the improvement of the bonding quality of the composite steel pipe.