Flux-cored wire for supporting roller built-up welding

Abstract

The invention discloses a flux-cored wire used in supporting roller overlaying welding. The weight percentages of the welding wire include that C is from 0.30 percent to 0.70 percent; Mn is from 0.20 percent to 0.60 percent; Si is from 0.10 percent to 0.40 percent; Cr is from 11.0 percent to 14.5 percent; Ni is from 1.0 percent to 8.0 percent; V is from 0.008 percent to 0.50 percent; Re is from 0.20 percent to1.00 percent; Mo is from 0.008 percent to 0.50 percent; Nb is from 0.08 percent to 0.50 percent; Ti is from 0.008 percent to 0.50 percent. It also can include one or two the following element that Mg is from 0.00 to 0.15 percent; Al is from 0.00 to 0.45 percent. The advantage of The invention discloses that the overlaying welding alloy has high hardness, good wear resistance, toughness and crack resistance, so that the using life of the supporting roller is improved.

Description

technical field [0001] The invention relates to a welding material, in particular to a flux-cored welding wire used for overlay welding of support rollers. Background technique [0002] Back-up rolls are large-scale metallurgical spare parts. Forged steel back-up rolls are mainly used in China. They are mainly used as auxiliary rolls for rolling in the steel rolling process. They are subjected to large alternating loads, and their working temperature is 150°C to 200°C. It is mainly due to normal temperature wear and the formation of lost blocks due to crack expansion. At present, some materials used in domestic back-up roller surfacing welding have low C content and low alloy element content in order to obtain better toughness, such as 30CrMnSi welding wire, whose composition is: C: 0.27-0.34%, Mn: 0.80-1.10 %, Si: 0.9~1.2%, Cr: 0.87~1.10%, low hardness (HRC35~40), poor wear resistance, it is difficult to meet the requirements for the use of support rolls; some in order to ...

AI Technical Summary

Problems solved by technology

At present, some materials used in domestic back-up roller surfacing welding have low C content and low alloy element content in order to obtain better toughness, such as 30CrMnSi welding wire, whose composition is: C: 0.27-0.34%, Mn: 0.80-1.10 %, Si: 0.9~1.2%, Cr: 0.87~1.10%, low hardness (HRC35~40), poor wear resistance, it is difficult to meet the requirements for the use of support rolls; some in order to obtain high hardness and achieve the purpose of wear resistance, The surfacing welding material contains more C, and a higher content of alloying elements is added, such as the EFW563 welding wire produced by Nantong Electric Melting Explosion Co., Ltd., its composition is: C: 1.5%, Si≤0.8%, Mn≤1.0%, Cr : 5.0%, Mo: 15%, Co: 0.8%, the hardness of the surfacing alloy is very high (HRC59~65), but the toughness is poor, and the carbides are mainly M 3 C-type carbide, which separates the matrix, reduces the continuity of the matrix, and weakens the toughness of the surfacing material. Under the action of a large alternating load, it is easy to generate cracks, crack expansion, and easy to form falling blocks.