Laser Surface Structuring of Cemented Carbide for improving the Strength of Induction Brazed Joints

Ahsan, Ammar; Kryukov, Igor; Böhm, Stefan

doi:10.3390/jmmp3020044

Cited by 5 publications

(2 citation statements)

References 15 publications

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“…The cutting and feed force experienced by the individual teeth of a bandsaw while cutting a stone is inherently different than those while cutting wood or metal. Due to harder inclusions, the process forces undergo large peaks (up to 3 times higher than the average force [1]) causing edge chipping and failure of the welded or brazed joints of the saw teeth [16]. Avoiding the direct contact between the blade and guides while cutting causes significant reduction in the vibration as indicated by the plots in Figure 9 comparing the surface roughness of the cut-off plate with and without the hydrostatic guides.…”

Section: Discussionmentioning

confidence: 99%

Hydrostatic Bandsaw Blade Guides for Natural Stone-Cutting Applications

Ahsan

Kenney

Kröger

et al. 2020

JMMP

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In a bandsaw machine, the blade guides provide additional stiffness and help to align the blade near the cutting region. Typically, these are either in the form of blocks made of carbide or ceramics or as sealed bearings. Abrasive particles, generated while cutting hard and brittle materials like natural stones, settle between the contact surfaces of the guides and the blade causing wear and premature failure. The hydrostatic guide system, as presented in this work, is a contactless blade guiding method that uses the force of several pressurized water jets to align the blade to the direction of the cut. For this investigation, cutting tests were performed on a marble block using a galvanic diamond coated bandsaw blade with the upper roller guides replaced by hydrostatic guides. The results show that the hydrostatic guides help to reduce the passive force to a constant near zero in contrast with the traditional guides. This also resulted in reduced surface roughness of the stone plates that were cut, indicating a reduction in laterial vibration of the band. Additionally, it has also been shown that using hydrostatic guides the bandsaw blade can be tilted to counter the bandsaw drift, opening opportunities for further research in active alignment control. This original research work has shown that the hydrostatic guide systems are capable of replacing, and in fact, perform better than state-of-the-art bearing or block guides, particularly for stone-cutting applications.

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Section: Discussionmentioning

confidence: 99%

Hydrostatic Bandsaw Blade Guides for Natural Stone-Cutting Applications

Ahsan

Kenney

Kröger

et al. 2020

JMMP

Self Cite

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“…Laser micro-textures can be classified into three main types: linear grooves ([ 76 , 92 , 100 ]), dimples ([ 101 , 102 ]), and rectangular pits ([ 58 , 103 , 104 ]). Other less used textures include elliptical ([ 105 , 106 , 107 ]), sinusoidal ([ 108 ]), chevron ([ 109 ]), and hybrid/texture combinations ([ 110 , 111 ]).…”

Section: Fabrication Of Surface Texturesmentioning

confidence: 99%

Laser Processing of Hard and Ultra-Hard Materials for Micro-Machining and Surface Engineering Applications

2021

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Polycrystalline diamonds, polycrystalline cubic boron nitrides and tungsten carbides are considered difficult to process due to their superior mechanical (hardness, toughness) and wear properties. This paper aims to review the recent progress in the use of lasers to texture hard and ultra-hard materials to a high and reproducible quality. The effect of wavelength, beam type, pulse duration, fluence, and scanning speed is extensively reviewed, and the resulting laser mechanisms, induced damage, surface integrity, and existing challenges discussed. The cutting performance of different textures in real applications is examined, and the key influence of texture size, texture geometry, area ratio, area density, orientation, and solid lubricants is highlighted. Pulsed laser ablation (PLA) is an established method for surface texturing. Defects include melt debris, unwanted allotropic phase transitions, recast layer, porosity, and cracking, leading to non-uniform mechanical properties and surface roughness in fabricated textures. An evaluation of the main laser parameters indicates that shorter pulse durations (ns—fs), fluences greater than the ablation threshold, and optimised multi-pass scanning speeds can deliver sufficient energy to create textures to the required depth and profile with minimal defects. Surface texturing improves the tribological performance of cutting tools in dry conditions, reducing coefficient of friction (COF), cutting forces, wear, machining temperature, and adhesion. It is evident that cutting conditions (feed speed, workpiece material) have a primary role in the performance of textured tools. The identified gaps in laser surface texturing and texture performance are detailed to provide future trends and research directions in the field.

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