Laser surface texturing of a WC-CoNi cemented carbide grade: surface topography design for honing application

Abrasive effectiveness of composite-like honing stones is related to the intrinsic surface topography resulting from the cubic boron nitride (CBN) grains protruding out of the metallic matrix. Within this framework, Laser Surface Texturing (LST) is implemented for replicating topographic features of a honing stone in a WC-base cemented carbide grade, commonly employed for making tools. In doing so, regular arrays of hexagonal pyramids (similar to CBN grains) are sculpted by a laser micromachining system. Micrometric precision is attained and surface integrity does not get affected by such surface modification. Finally, potential of laser-patterned cemented carbide tools, as alternative to conventional honing stones, is supported by successful material removal and enhanced surface smoothness of a steel workpiece in the abrasive testing.Peer ReviewedPostprint (author's final draft

Fundamental Study of Corrective Abrasive Machining Technology

The presentation give an overview on the research activities undertaken in the AMTG, CPT in the University of Huddersfield

К вопросу о функциональном действии технологических сред при абразивной обработке кругами из сверхтвердых материалов

В данной статье рассматриваются вопросы использования смазочно-охлаждающих технологических сред применительно к процессам абразивной обработки шлифовальным инструментом из СТМ. Приведены сведения по явлениям, сопровождающим применение технологических сред, показаны их действия и функции при использовании в процессах абразивной обработки.This article focuses on the effective use of lubrication-cooling technological environments as applied to the processes of abrasive machining with the grinding tool made of extra-hard materials. The article provides the information on the effects of the technological environments usage and describes their operational properties and functions in the abrasive machining processes

Wear characterization of cemented carbides (WC-CoNi) processed by laser surface texturing under abrasive machining conditions

Cemented carbides are outstanding engineering materials widely used in quite demanding material removal applications. In this study, laser surface texturing is implemented for enhancing, at the surface level, the intrinsic bulk-like tribological performance of these materials. In this regard, hexagonal pyramids patterned on the cutting surface of a tungsten cemented carbide grade (WC-CoNi) have been successfully introduced by means of laser surface texturing. It simulates the surface topography of conventional honing stones for abrasive application. The laser-produced structure has been tested under abrasive machining conditions with full lubrication. Wear of the structure has been characterized and compared, before and after the abrasive machining test, in terms of changes in geometry aspect and surface integrity. It is found that surface roughness of the machined workpiece was improved by the laser-produced structure. Wear characterization shows that laser treatment did not induce any significant damage to the cemented carbide. During the abrasive machining test, the structure exhibited a high wear resistance. Damage features were only discerned at the contacting surface, whereas geometrical shape of pyramids remained unchanged.Peer ReviewedPostprint (author's final draft

Wear Characterization of Cemented Carbides (WC–CoNi) Processed by Laser Surface Texturing under Abrasive Machining Conditions

Cemented carbides are outstanding engineering materials widely used in quite demanding material removal applications. In this study, laser surface texturing is implemented for enhancing, at the surface level, the intrinsic bulk-like tribological performance of these materials. In this regard, hexagonal pyramids patterned on the cutting surface of a tungsten cemented carbide grade (WC–CoNi) have been successfully introduced by means of laser surface texturing. It simulates the surface topography of conventional honing stones for abrasive application. The laser-produced structure has been tested under abrasive machining conditions with full lubrication. Wear of the structure has been characterized and compared, before and after the abrasive machining test, in terms of changes in geometry aspect and surface integrity. It is found that surface roughness of the machined workpiece was improved by the laser-produced structure. Wear characterization shows that laser treatment did not induce any significant damage to the cemented carbide. During the abrasive machining test, the structure exhibited a high wear resistance. Damage features were only discerned at the contacting surface, whereas geometrical shape of pyramids remained unchanged

Influence of roughness on contact interface in fretting under dry and boundary lubricated sliding regimes

This paper presents experimental results of wear process under dry and boundary lubricated metallic (AISI 1034/AISI 52100) contacting bodies with different surfaces morphologies subjected to a wide range of kinematic fretting conditions. Analysis of damage mode observed under such fretting conditions is elucidated in context of surfaces morphologies therefore associated with surface manufacturing processes. Various surface topographies due to specific machining processes (cutting and abrasive modes) have been investigated. Under boundary lubricated (ZDDTP zinc-dialkyl-dithiophosphate) fretting contact paradoxally has a high coefficient of friction at the transition between Partial and Full slip sliding regime. This paper attempts to bridge the gap between the damage mode, sliding conditions and surface roughness to provide an approach to evaluate the surface finishing as a factor in friction and wear damage processes

Microstructure and corrosion resistance of magnesium alloys with galvanic coatings

AbstractThe article presents the technology of obtaining the galvanic coatings on the ready structural elements made of Mg-Al magnesium alloys. The technology was developed in NTP CIBIS Ltd in cooperation with the Silesian University of Technology. The influence of the mechanical surface preparation and deposition on the basis of sulfamate nickel and copper plating on the layer quality and corrosion resistance were described. The final galvanic layer with a new type of intermediate sulfamate nickel layer is characterized by high uniformity irrespective of an observation location. Corrosion resistance of the elements with the coatings deposited on the surfaces vibro-abrasively machined is much higher than that of the coatings deposited on the surfaces ground and polished

Influence of magneto-abrasive machining on the quality keyway mills made of high speed steel

Досліджено вплив швидкості обертання шпонкових фрез виготовлених з швидкорізальної сталі навколо власної осі в процесі магнітно-абразивного оброблення в робочих зонах кільцевого типу та складу магнітно-абразивного інструменту на показники якості. Встановлено, що збільшення швидкості обертання фрез навколо власної осі в досліджуваному діапазоні призводить до підвищення поверхневої твердості, зменшує інтенсивність формування радіусу округлення різальних кромок та суттєво не впливає на зміну шорсткості робочих поверхонь. Проведено дослідження працездатності шпонкових фрез після циклу магнітно-абразивного оброблення, показано, що відбувається підвищення їх стійкості в 2 і більше рази в порівнянні з необробленими. Встановлено, що найбільше на працездатність впливає величина та форма радіусу округлення різальних кромок та поверхнева твердість різального інструменту.Experimental investigations of influences of magneto-abrasive machining conditions on the quality parameters of keyway mills made of high speed steel were carried out. It was determined that an increasing in angular velocity of mills around its own axis during the machining does not lead to the intensification reducing of roughness parameters and formation radiuses of cutting edge rounding. But it increases the hardness of working surfaces due to the frictional hardening. The best results for hardening were obtained at using powdered with round shape, which provides increasing of hardness to value 10-11,5 GPa at the initial 8-9 GPa, reduction of roughness at using splinter powders with high abrasive ability, which provides value of Ra 0,45 µm at the initial 1,4 µm. By using the method of magneto-abrasive machining can be increased the keyway mills tool life by forming the necessary size of radiuses of cutting edge rounding and increasing of the hardness of the surface layers of the working elements. Experimen tally was investigated that at the angular velocity of mills around its own axis 500 rpm and using as magneto-abrasive material the diffuse powder made from PR R6M5 with grain size 160/100 µm the tool life increases in 2-2,3 times

Магнитно-абразивная обработка конических поверхностей деталей машин

AKULOVICH LM, SERGEYEV LE, BABICH VE, SENCHUROV EV, PADALYAK V.V. Magnetic-abrasive machining of conical surfaces of machine partsПриведены результаты использования способа магнитно-абразивной обработки для финишной обработки концов шпинделей. Магнитно- абразивная обработка обеспечивает требуемые шероховатость и физико- механические характеристики поверхности концов шпинделей

Manufacturing Processes of Integral Blade Rotors for Turbomachinery, Processes and New Approaches

Manufacturing techniques applied to turbomachinery components represent a challenge in the aeronautical sector. These components are commonly composed of high resistant super-alloys; in order to satisfy the extreme working conditions, they have to support during their useful life. Besides, in the particular case of Integrally Bladed Rotors (IBR), they usually present complex geometries that need to be roughed and finished by milling and grinding processes, respectively. Thermoresistant superalloys present many challenges in terms of machinability what leads to find new alternatives to conventional manufacturing processes. In order to face this issue, this work presents a review of the last advances for IBR manufacturing and repairing processes.We are grateful to Basque Excellence university Groups IT IT1337-19, and Ministry of economy project IBRELIABLE (DPI2016-74845-R), and Elkartek PROCODA KK 2019-004