Laser-induced plasma micro-machining (LIPMM) for enhanced productivity and flexibility in laser-based micro-machining processes

This paper explores the modeling of incipient cutting by Abaqus, LS-Dyna, and Ansys Finite Element Methods (FEMs), by comparing also experimentally the results on different material classes, including common aluminum and steel alloys and an acetal polymer. The target application is the sustainable manufacturing of gecko adhesives by micromachining a durable mold for injection molding. The challenges posed by the mold shape include undercuts and sharp tips, which can be machined by a special diamond blade, which enters the material, forms a chip, and exits. An analytical model to predict the shape of the incipient chip and of the formed grove as a function of the material properties and of the cutting parameters is provided. The main scientific merit of the current work is to approach theoretically, numerically, and experimentally the very early phase of the cutting tool penetration for new sustainable machining and micro-machining processes.

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Experimental Investigation Into Sequential Micro Machining (SMM) for Micro Hole Drilling on SS–304

International Journal of Manufacturing Materials and Mechanical Engineering ◽

10.4018/ijmmme.2019100101 ◽

2019 ◽

Vol 9 (4) ◽

pp. 1-16

Author(s):

Raju Mahadeorao Tayade ◽

Biswanath Doloi ◽

Biplab Ranjan Sarkar ◽

Bijoy Bhattacharyya

Keyword(s):

Xrd Analysis ◽

304 Stainless Steel ◽

Hole Drilling ◽

Machining Parameters ◽

Micro Machining ◽

Machining Processes ◽

Taper Angle ◽

Micro Holes ◽

Micro Hole ◽

Ss 304

Sequential micro machining (SMM) is a strategy of machining applied for micro-part manufacturing. Due to the finding of new sequential machining combinations, the authors have presented a novel combination of micro-ECDM (µECDM) drilling and micro-ECM (µECM) finishing for producing micro-holes in SS-304 stainless steel. An experimental setup was developed indigenously to conduct both machining processes at one station. The sequential processes were employed with desirable machining parameters, during their individual execution. The most desirable parameter like machining voltage, for hole drilling by µECDM was decided by studying hole taper angle, radial overcut, etc. The µECDM generates a recast layer, to overcome the adverse effects of µECDM, with the µECM finishing applied subsequently. The experimental results of SMM indicate a reduction in hole taper angle, improved circularity, and better surface quality. The change of phase of material due to sequencing of µECDM and µECM processes was analyzed by an XRD analysis of SS-304.

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Multi-Material Capability of Laser Induced Plasma Micromachining

Volume 1: Materials; Micro and Nano Technologies; Properties, Applications and Systems; Sustainable Manufacturing ◽

10.1115/msec2014-4142 ◽

2014 ◽

Author(s):

Ishan Saxena ◽

Kornel Ehmann

Keyword(s):

Laser Ablation ◽

Metal Cutting ◽

Medical Engineering ◽

Machining Process ◽

Micro Machining ◽

Promising Alternative ◽

Laser Induced Plasma ◽

Direct Laser ◽

Micro Features ◽

Machining Characteristics

Presently surface micro-texturing has found many promising applications in the fields of tribology, bio-medical engineering, metal cutting, and other functional or topographical surfaces. Most of these applications are material-specific, which necessitates the need for a texturing and machining process that surpasses the limitations posed by a certain class of materials that are difficult to process by laser ablation, owing to their optical or other surface or bulk characteristics. Laser Induced Plasma Micromachining (LIPMM) has emerged as a promising alternative to direct laser ablation for micro-machining and micro-texturing, which offers superior machining characteristics while preserving the resolution, accuracy and tool-less nature of laser ablation. This study is aimed at understanding the capability of LIPMM process to address some of the issues faced by pulsed laser ablation in material processing. This paper experimentally demonstrates machining of optically transmissive, reflective and rough surface materials using LIPMM. Apart from this, the study includes machining of conventional metals (Nickel and Titanium) and polymer (Polyimide), to demonstrate higher obtainable depth and reduced heat affected distortion around micro-features machined by LIPMM, as compared to laser ablation.

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On the Modeling of Friction in Micromachining Processes

ASME/STLE 2007 International Joint Tribology Conference, Parts A and B ◽

10.1115/ijtc2007-44196 ◽

2007 ◽

Author(s):

M. R. Lovell ◽

P. H. Cohen ◽

R. Shankar

Keyword(s):

Friction Mechanisms ◽

Machining Process ◽

Micro Machining ◽

Machining Processes ◽

Macroscopic Theory ◽

Contact Conditions ◽

Macro Scale ◽

Scale Models ◽

Basic Understanding ◽

Physical Phenomena

When machining miniaturized components, the contact conditions between the tool and workpiece exhibit very small contact areas that are on the order of 10−5 mm2. Under these conditions, extremely high contact stresses are generated and it is not clear whether macroscopic theories for the chip formation, cutting forces, and the friction mechanisms are applicable. For this reason, the present investigation has focused on creating a basic understanding of the frictional behavior in micro machining processes so that evaluations of standard macro-scale models could be performed. Specialized machining experiments were conducted on 70/30 brass materials using steel tools over a range of speeds, feeds, depths of cut and tool rake angles. At each operating condition studied, the friction coefficient and the shear factor, τk, were obtained. Based on the experimental results, it was determined that standard macroscopic theory for analyzing detailed friction mechanisms was insufficient in micro machining processes. An approach that utilized the shear factor, in contrast, was found to be better for decoupling the physical phenomena involved. Utilizing the shear factor as an analysis parameter, the parameters that significantly influence the friction in microscale machining process were ascertained and discussed.

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Line-Based Laser Induced Plasma Micro-Machining (L-LIPMM)

Volume 2: Systems; Micro and Nano Technologies; Sustainable Manufacturing ◽

10.1115/msec2013-1153 ◽

2013 ◽

Cited By ~ 1

Author(s):

Rajiv Malhotra ◽

Ishan Saxena ◽

Kornel Ehmann ◽

Jian Cao

Keyword(s):

Laser Ablation ◽

Process Parameters ◽

Ultrashort Pulse ◽

Experimental Setup ◽

Micro Machining ◽

Ultrashort Pulse Laser ◽

Plasma Generation ◽

Laser Induced Plasma ◽

Laser Micro Machining ◽

Wide Range

Recently, the technique of Spot-based Laser Induced Plasma Micro-Machining (Spot-LIPMM) has been developed to address the limitations of conventional ultrashort pulse laser micro-machining. Its main advantages are adaptability to a wide range of materials and superior wall geometries. We propose a variation of the Spot-LIPMM process by creating line plasma instead of spot plasma, with the use of suitable optics. This paper describes the experimental setup used to create line plasma and the process used for micro-machining with L-LIPMM. Optics simulations are developed as a means of guiding the choice of optics to be used for line plasma generation and estimating the energy and shape of the plasma created. It is shown that this Line-based LIPMM (L-LIPMM) process is capable of micromachining channels at a much higher speed than conventional Spot-based laser ablation or spot-based LIPMM. Additionally, the effects of process parameters on machined geometry using L-LIPMM are discussed.

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Simulation of Ultrashort Laser Pulse Absorption At the Water-metal Interface in Laser-Induced Plasma Micro-Machining

Journal of Micro and Nano-Manufacturing ◽

10.1115/1.4049360 ◽

2020 ◽

Author(s):

Jiaxi Xie ◽

Kornel Ehmann ◽

Jian Cao

Keyword(s):

Dielectric Breakdown ◽

Constitutive Relations ◽

Three Dimensional ◽

Optical Breakdown ◽

Micro Machining ◽

Metal Interface ◽

Breakdown Threshold ◽

Laser Induced Plasma ◽

Water Metal ◽

Ultrashort Laser

Abstract This work proposes a physically consistent numerical model to simulate ultrashort laser absorption by a metallic workpiece at the water-metal interface when optical breakdown of the dielectric occurs. The simulation couples the framework of the Finite-Difference Time-Domain method used in computational electromagnetics with the constitutive relation derived from both the model of direct ablation of metals and the first order model of water breakdown. The simulation is used to describe interface ablation processes such as Laser-Induced Plasma Micro-Machining. Applied to the water-aluminum interface, the model is able to describe the metal absorption and the dielectric breakdown threshold in three-dimensional geometry. It is an extensible monolithic approach in which the absorption by different materials can be described by simply changing the constitutive relations.

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Investigation on the evolution and distribution of plasma in magnetic field assisted laser-induced plasma micro-machining

Journal of Manufacturing Processes ◽

10.1016/j.jmapro.2021.09.017 ◽

2021 ◽

Vol 71 ◽

pp. 197-211

Author(s):

Yanming Zhang ◽

Suman Bhandari ◽

Jiaxi Xie ◽

Guojun Zhang ◽

Zhen Zhang ◽

...

Keyword(s):

Magnetic Field ◽

Micro Machining ◽

Laser Induced Plasma

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Micro Machining Simulation Analysis by Finite Element Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.712-715.575 ◽

2013 ◽

Vol 712-715 ◽

pp. 575-578

Author(s):

Zhan Min Yin ◽

Yu Juan Dai

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Simulation Analysis ◽

Cutting Speed ◽

Failure Criteria ◽

Rake Angle ◽

Depth Of Cut ◽

Micro Machining ◽

Machining Processes ◽

Element Method

Micro machining becomes more and more important with the tendency of miniaturization of components used in various fields from military to civilian applications. The finite element method software Abaqus is used to model the nonlinear thermal force coupled elastic-plastic micro machining processes. Relatively systematic simulation analysis has been introduced based on the model combining the Johnson-Cook failure criteria, element deletion strategy etc. It reveals that the size effect is dominant while the depth of cut reaches the cutting edge radius. The rake angle plays more important roles on the micro machining than that of the cutting speed.

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A Comparison among Dry Laser Ablation and Some Different Water-Laser Co-Machining Processes of Single Crystal Silicon Carbide

Materials Science Forum ◽

10.4028/www.scientific.net/msf.861.3 ◽

2016 ◽

Vol 861 ◽

pp. 3-8 ◽

Cited By ~ 3

Author(s):

Shao Chuan Feng ◽

Chuan Zhen Huang ◽

Jun Wang ◽

Hong Tao Zhu ◽

Peng Yao ◽

...

Keyword(s):

Silicon Carbide ◽

Laser Ablation ◽

Single Crystal ◽

Thermal Damage ◽

Single Crystal Silicon ◽

Micro Machining ◽

Machining Processes ◽

Crystal Silicon ◽

Machine Material ◽

Single Crystal Sic

Single crystal silicon carbide (SiC) is a new semiconductor material that has a great potential to be widely used. However, SiC is a kind of difficult-to-machine material due to its extreme hardness and brittleness. The present study investigated the machinability of single crystal SiC using dry laser and three different water-laser co-machining processes. The results indicate that using the hybrid laser-waterjet micro-machining to micro-groove single crystal SiC can derive the clean and straight edges and thermal damage-free grooves.

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High Precision Machine Based on a Differential Mechanism

Volume 2: Dynamics, Vibration and Control; Energy; Fluids Engineering; Micro and Nano Manufacturing ◽

10.1115/esda2014-20078 ◽

2014 ◽

Cited By ~ 4

Author(s):

Alberto Borboni ◽

Elisabetta Ceretti ◽

Alessandro Copeta ◽

Davide Moscatelli ◽

Rodolfo Faglia ◽

...

Keyword(s):

High Precision ◽

Degrees Of Freedom ◽

Static Friction ◽

Micro Machining ◽

Concept Design ◽

Machining Processes ◽

Precision Machine ◽

Macro Scale ◽

Differential Mechanism ◽

Servo Drives

Micromachining processes deal with the production of parts characterized by features in the micro range (i.e., with dimension lower than 1 mm). Several works are present in literature analyzing the tool behaviors, the material influence on the process, and the machine design. In fact, the downsize of the process up to the microscale needs a full review of all the knowledge coming from the meso and macro scale. As a consequence, machines suitable for micromachining processes were recently introduced in the market. Usually, these machines are classified by the classical gantry layout structure supported by a granite frame and, in order to guarantee the needed requirements of precision and accuracy in the micro scale, they are based on fluid-supported axes and active and/or passive vibration control systems. This paper proposes a new concept design: a high precision machine (HPM) based on an innovative layout exploiting a differential mechanism with three motors for two degrees of freedom using pulleys and metal belts. This new layout exhibits relevant advantages. The most significant is that all the worktable servo drives, that moves along x and y axes, are ground-fixed. This allows to isolate the working area of the machine from the servo drives. The system of pulleys and belts holding the working table slides on air bearings in order to minimize the micro vibrations induced by all the drives. A further peculiarity of the machine consists of the double z-axis each of them is motorized by a micrometer slide with linear absolute encoder. The first z-axis is equipped with a spindle for performing micro machining processes (drilling and milling). The second z-axis is equipped with a laser head for micro ablation. The servo drives of the two z-axes are controlled by the same control system of the worktable. Another important feature of the proposed layout is that the differential configuration of the xy mechanism admits the use of a constant speed signal to each control reference with no output displacements. This allows to guarantee non-inversion of motion of the servo-drives and so the avoidance of problems due to backlash and/or static friction. Drives are controlled by position and speed control loops with PID architecture, anti-windup and feed forward strategies. Controllers have been tuned by the use of a genetic algorithm applied to a dynamic model of the system. As a general consideration, the quality of the investigated micro machining processes can be improved with the designed machine structure.

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