Influence of laser machining process on the ablation amount and organizational properties of cemented carbide

Abstract

Laser processing technology, with its non-contact, high-precision characteristics, has brought new hope for the processing of cemented carbide tools, and greatly expanded the application potential of cemented carbide. But there is a lack of research on the mechanism of laser ablation and material evolution of cemented carbide materials. This study examines the factors that influence the amount of ablation through two-factor experiments. Two laser machining processes, namely the Variable Parameter Indexing Alternate Machining (VPIAM) process and the Laser Enhanced Preparation Machining (LEPM) process,are proposed and compared to the conventional Unidirectional Continuous Ablation Machining (UCAM) process. To investigate the effects of the three processes on cemented carbide, comparative analyses of ablation amount, organizational properties, surface morphology, and surface roughness of the materials were performed under the three machining processes, and the relevant mechanisms were summarized. In this study, the power, pulse overlap rate, and line overlap rate of laser processing were regulated, and the experimental data were integrated. The results showed that the backfill effect occurs under the remelting and slag deposition effects, and the amount of material ablation under UCAM is small. The VPIAM technique effectively reduces the hindrance of slag and remelting during the ablation process by integrating slag removal and indexing processing. The increase in material ablation can range from 13.07 to 60.2 um, with a growth rate of 236–628 %. Using the LEPM process, the remelted layer undergoes several laser shocks, resulting in the total elimination of micro-cracks. Furthermore, the material particles within the reinforced layer undergo a refinement process, and some of these particles form bonds with the remelted layer. The layer reinforced with material exhibits a higher degree of uniformity and straightness, enhancing the surface characteristics of the processed material to some extent.