Thermal Effect Analysis of Laser Processing Cemented Carbide Micro-texture

Abstract

Laser surface microtexturing techniques can improve the friction properties of materials by reducing the contact area and form heat affected zones (HAZ) by energy conduction in laser processing. HAZ has a significant effect on the surface friction properties in the friction zone. This paper focuses on the formation of HAZ on the surface of cemented carbide during laser processing micro-texture. Firstly, the principle of energy absorption, conversion and conduction in laser processing is analyzed. Then the finite element method is used to study the distribution of temperature field and its change with time. Then the laser processing of microtexture of cemented carbide is carried out by laser marking machine. In the experiment, the characteristics of HAZ on the surface of cemented carbide after laser processing were studied by ultra-depth microscope, EDS and SEM. The effects of different laser processing parameters on the size of HAZ were studied, and the changes of element content after laser processing were studied. At the same time, the morphology of HAZ microcracks was observed and the reasons for its formation were analyzed. The results show that the laser power is the main factor affecting the HAZ size, followed by the laser scanning speed and the number of scans. The content of Co after laser processing is highest near the center of the micro-texture, and decreases from the center to the edge. The thermal stress and stress concentration caused by the temperature gradient cause microcracks to form around and inside the microtexture. By selecting reasonable laser parameters, it has an important influence on the size, element content and microcrack formation of HAZ, and it is of great significance to improve the micro-texture properties of the processed cemented carbide.

Structural modification of WC-Co cutting tools by laser doping treatment

“…To improve the interfacial bond strength between the cutting tool edge and coating, researchers have developed surface modification techniques such as microblasting [ 19 , 20 ], laser peening [ 21 ], microstructural and surface modification using pulsed lasers [ [22] , [23] , [24] ], and Co removal [ 25 ]. In addition to improving the bond strength between the cutting tools and coatings, blast polishing [ 26 ], surface modification and microstructure formation using femtosecond lasers [ 27 , 28 ], laser peening [ 29 ], and surface modification with high-intensity pulse ion beams [ 30 ] have been attempted.…”

Wear Resistance of Stellite-6/TiC Coating on Stainless Steel 316L Produced by Laser Cladding Process

“…Among other methods, laser surface treatment has attracted greater interest because laser process parameters (laser power, laser scanning speed, feed rate etc.) provides negligible Heat Affected Zone (HAZ), precise heat input, low residual stress, low distortion, high speed and productivity, good accuracy and surface finish, strong metallurgical bond with minimal dilution, near zero wastage material, greater flexibility and reliability without effecting the material, mechanical and chemical properties of the base material [6][7][8][9].…”