Surface Strengthening Technology for Hammers of a Four-Die Forging Device

Abstract

Strengthening of the hammers of four-die forging devices is considered in this paper. During the manufacture of forgings of future details from high-quality and alloy steels, the hammers of four-die forging devices work in extreme conditions of shock-abrasive wear, which causes them to fail quickly. Various technological methods of their strengthening are applied to prolong the service life of the hammers. One of the promising ways of strengthening the details of forging and pressing equipment is surfacing technology. The existing method of strengthening the hammer’s surface of radial forging machine by surfacing with electrodes OZSh-6 and its disadvantages is described. A new method of strengthening the hammer’s working surface using a welding machine by flux-cored wire PP-NP-35X6M2 is proposed. It was found that when surfacing AISI L6 tool steel with this flux-cored wire, the hardness of the metal surface after surfacing increases to 53 HRC, and when moving inwards, the hardness decreases to 44 HRC, which indicates a soft and viscous structure that can withstand dynamic loads. There is also an increase in the strength and wear resistance of the detail’s surface, which, when surfacing with flux-cored wire PP-NP-35H6M2, is greater than the base metal by 1.5 times. Experimental studies, which have been obtained on the structure, hardness, and wear resistance, confirmed the feasibility of replacing manual arc welding with automatic.