关键词: 热轧, 夹送辊, 力学性能, 显微组织, 耐磨性

Abstract: In order to improve the properties of the pinch roller and extend its service life, the current Delstain-442 welding wire and the proposed Multipass-249 and Multipass-224HC welding wires were studied. The microstructure and properties changes of the surfacing layers prepared by the three types of welding wires after annealing at 500 ℃ and 540 ℃ were compared. The results indicate that after annealing, the retained austenite in the three types of surfacing layers transformed into martensite, and the transformation of the Delstain-442 layer is more complete. The Multipass-249 layer annealed at 540 ℃ has better toughness, more stable microstructure, and better high-temperature wear resistance. The Delstain-442 layer annealed at 540 ℃ can also achieve better high-temperature hardness and high-temperature wear resistance. The Multipass-224HC layer has higher brittleness, while obtains good wear resistance after annealing at both the temperatures, where the wear rate is reduced by one order of magnitude compared to that of the Delstain-442. The comprehensive properties of the Multipass-249 layer annealed at 540 ℃ are good, but due to doubts about its impact toughness, further verification is needed to determine whether it can replace the Delstain-442.

Key words: hot rolling, pinch roller, mechanical properties, microstructure, wear resistance