Research into the Effect of Temperature Fields of Heating during Continuous Laser Treatment on the Performance of the T15K6 Carbide Insert Plates

Abstract

The effect of temperature fields of heating during continuous laser treatment on the performance of the T15K6 carbide insert plates is studied. A tool with T15K6 indexable carbide inserts is exposed to laser treatment by heating the working surface with continuous laser emission using an LK 3015ls07 industrial laser according to the KV_OSN program along the insert contours with a distance from the cutting edge of ~2 mm. The laser exposure time is 2–3 s using nitrogen as a shielding medium. The samples shaped as tetrahedral plates 12 × 12.70 × 4.76 mm in size (GOST (State Standard) 19050–80) are used for the investigation. The emission power density varies in the range q = 300 ± 100 W/cm² and laser-beam moving speed varies as V_L = 20 ± 10 mm/s. The hardness of the laser-hardened zone after laser exposure is H_μ = 15 500–21 500 N/mm². The laser impingement region was tested for cutting and abrasive wear, and microstructural analysis was performed. The cutting wear along the front and back surfaces of carbide inserts after laser treatment decreased fivefold. It is shown that a further increase in laser power density up to q = 400 W/cm² does not provide a positive trend. The diamond-abrasive wear with an increase in q is accompanied by wear reduction to 40 wt %. Microstructural analysis showed a decrease in the tungsten carbide grain size in a continuous laser treatment region from 5.6 to 4.3 μm.