Metal powder for repairing supporting roll based on laser coaxial powder feeding process and preparation method of metal powder

Abstract

The invention relates to metal powder for repairing a supporting roll based on a laser coaxial powder feeding process and a preparation method of the metal powder. The powder comprises, in percentageby mass, the following chemical components of 0.4-0.5% of C, 0.2-0.5% of Si, 0.2-0.5% of Mn, <=0.02% of P, <=0.015% of S, 4.5-5.5% of Cr, 0.15-0.82% of Ni, 0.2-0.4% of Mo, 0.1-0.2% of V, <=0.03% of O,<=0.03% of N and the balance of Fe and inevitable impurities. The metal powder is successfully applied to cold roll laser coaxial powder feeding repair, the Rockwell hardness is 52-58HRC, the on-lineservice cycle of the repaired supporting roll is 45-51 days, the on-line service cycle is long, and the service life of the supporting roll is prolonged.

Description

technical field [0001] The invention belongs to the technical field of 3D printing technology powder preparation, and in particular relates to a metal powder for repairing backup rollers based on a laser coaxial powder feeding process and a preparation method thereof. Background technique [0002] Cold-rolled back-up rolls are equipment on the cold-rolled continuous annealing production line. Cr5 alloy forged steel rolls are commonly used now, and the hardened layer is set on the roll surface. Laser quenching technology is generally used, and the layer thickness is up to 100mm; its main function is to prevent the work rolls from being rolled Deflection deformation occurs during rolling and affects the flatness and quality of the rolled plate. Its service conditions are complex and harsh, and it needs to bear the additional stress caused by irregular wear, roll bending force, rolling impact, etc. The working pressure of the roll surface is about 1000t. Some even reach more th...

AI Technical Summary

Problems solved by technology

There are two main failure forms of cold rolling rolls: one is fatigue wear, and the size of the workpiece reaches the limit size of the rolling mill; the other is due to excessive stress, cracks or peeling and dents on the roll surface during the rolling process, and roll surface defects will directly cause product surface damage. Defects require timely replacement or repair of failed backup rolls

[0003] After the back-up roll has surface defects, the depth of the surface depression is generally 5-15mm. Most domestic manufacturers use brand-new back-up rolls to ensure the surface quality of the product, but the cost is too high, so the demand for surface repair of cold rolls continues to increase.

The current conventional repair method is the CMT arc additive manufacturing method. Due to the large heat-affected zone of this repair method, welding defects such as cracks, pores, and slag inclusions are prone to occur, and the surfacing layer is easy to peel off. After repair, the repair quality of the roller surface and The degree of bonding between the repair material and the matrix cannot be guaranteed, and the back-up roll does not have the conditions for re-service under this process condition

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