Thermal Management in Laser Assisted Machining: A Preliminary Study

The use of laser in manufacturing has gained considerable attention recently. In non-reactive processes, the laser beam is used either to machine, to weld, or to modify the target material structure by local heating. In addition to elevating the surface temperature of the target, this local heating may significantly alter the material crystalline structure; change its phase, and thus the electrical, mechanical and thermal properties. For reliability and consistency, it is necessary to control effectively the laser-based manufacturing processes. Specifically, the induced micro-structural changes due to the heat transfer mechanisms have to be analyzed. Most importantly, the thermal effect on the sub-surface microstructures and the generated thermal stress distribution need to be well quantified. The application of lasers in manufacturing has distinctive advange when dealing with ceramic material. The use of advanced ceramics has doubled in the past ten years, and is expected to grow at an even faster pace in the new millennium. The superior properties, such as low weight, high temperature strength and wear/corrosion resistance, of these structural ceramics make them the preferred materials in various applications including bearings, rollers/followers, valves, engines, cutting tools and even artificial joints in the human body. The major goal of this study is to develop an innovative laser-assisted drilling process through innovative tool design and cooling method. A preliminary investigation of the effect of donut-shaped laser heat input on the temperature distribution in the workpiece is studied numerically and experimentally.

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Micro Evaluation of Sulphonamide in Biological Samples by Coupling Reaction

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.10.3.35 ◽

2020 ◽

Vol 10 (03) ◽

pp. 509-512

Author(s):

Aliaa A. Razzak Mohammed ◽

Ahmed J. Muklive Al-Ogaidi ◽

Abeer Abdul Razak Mohammed

Keyword(s):

Biological Samples ◽

Structural Changes ◽

Antitumor Agents ◽

Low Cost ◽

Preliminary Investigation ◽

Target Material ◽

Coupling Reaction ◽

Amino Compound ◽

Stability Factor ◽

Colored Complex

Sulphonamide is considered a turning point for therapeutic science. Structural changes in sulphonamide can lead to the formation of various drugs used for combating different diseases. Sulphonamide can be used in different applications, such as, antitumor agents, carbonic anhydrase inhibitors, anti-bacterials, hypoglycaemic agents, protease inhibitors, and diuretics. The most important thing for this assay is to find a modified approach to assess sulphonamide by utilizing an organic reaction that depends on a process of coupling between our target material (sulphonamide) with 4-amino antipyrine in basic media of phosphate buffer (pH = 11.3), forming a colored complex containing a higher molar absorptivity (wavelength = 457 nanometers). A preliminary investigation test was done to determine the typical condition for this reaction to determine the concentration curve for the interval 8.25 × 10-9 to 1.15 × 10-2 ppm, and the absorptivity molar was 2.1 × 104 L.mol-1.cm-1, RSD value greater than 1.12%, with a percentage of recovery of approximately 99.88%. We obtained the result and got the approved mole ratio for this reaction about 1:1 (sulphonamide:diazotized amino compound); the value of the stability factor reached 2.8 × 106 L.mol-1. This proposal could be used for a fair assessment for sulphonamide determination, which has different advantages, such as, low-cost economy, no need for an expert, simplicity, no need for more time, and high-quality results in the requirement of rapid and excellent determination. This approach can be utilized for validation of sulphonamide in different active biological samples with higher efficiency.

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FE Simulation of Laser Assisted Bending

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.6-8.745 ◽

2005 ◽

Vol 6-8 ◽

pp. 745-752 ◽

Cited By ~ 1

Author(s):

M. Pitz ◽

Marion Merklein

Keyword(s):

Structural Changes ◽

Local Heating ◽

High Surface ◽

Cutting Tools ◽

Conventional Heating ◽

Roll Forming ◽

Heating Rates ◽

Heating And Cooling ◽

Steel Grades ◽

Multi Phase

Steel has a long tradition and is used in nearly every application. In order to be able to compete with other lightweight materials over and over again new steel grades are developed. Interesting steel grades, which are especially suitable for the lightweight construction in the automotive industry, are the multi-phase steels. Multi-phase steels reach already yield strengths over 1000 MPa. This is a challenge for the production engineering. Drawing, forming and cutting tools must be stiff and hard and/or coated, lubricants have to decrease friction to avoid damages induced by the high surface pressures. The designers have to consider the small forming capability by large radii or reduced drawing depths. To overcome these disadvantages new, innovative forming processes, e.g. laser assisted bending or roll forming, have to be developed. In the forming technique it is known that the forming limits can be increased by warm forming. But the conventional heating systems may cause unwanted changes of the material regarding to the structure and the mechanical properties. In the case of multi-phase steels e.g. the hard phases martensite and bainit can be transformed into ferrite and therefore the yield stresses can be changed clearly. In contrast to this laser assisted bending minimizes structural changes due to the local heating of the forming area. Beside the advantage, that only a small area of the bending part is exposed with a thermal load, the heating up with the laser permits high heating rates and also a controlling of the heating and cooling rates, so that the heating and cooling can be adapted to the material and its properties. In the context of this paper parameter studies with FE simulations of the laser assisted bending process are presented.

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Effect of Cutting Parameters and Tool Geometry on the Performance Analysis of One-Shot Drilling Process of AA2024-T3

Metals ◽

10.3390/met11060854 ◽

2021 ◽

Vol 11 (6) ◽

pp. 854

Author(s):

Muhammad Aamir ◽

Khaled Giasin ◽

Majid Tolouei-Rad ◽

Israr Ud Din ◽

Muhammad Imran Hanif ◽

...

Keyword(s):

Feed Rate ◽

Surface Defects ◽

Thrust Force ◽

Cutting Tools ◽

Chip Thickness ◽

Cutting Parameters ◽

Spindle Speed ◽

Machining Process ◽

Tool Geometry ◽

Drilling Process

Drilling is an important machining process in various manufacturing industries. High-quality holes are possible with the proper selection of tools and cutting parameters. This study investigates the effect of spindle speed, feed rate, and drill diameter on the generated thrust force, the formation of chips, post-machining tool condition, and hole quality. The hole surface defects and the top and bottom edge conditions were also investigated using scan electron microscopy. The drilling tests were carried out on AA2024-T3 alloy under a dry drilling environment using 6 and 10 mm uncoated carbide tools. Analysis of Variance was employed to further evaluate the influence of the input parameters on the analysed outputs. The results show that the thrust force was highly influenced by feed rate and drill size. The high spindle speed resulted in higher surface roughness, while the increase in the feed rate produced more burrs around the edges of the holes. Additionally, the burrs formed at the exit side of holes were larger than those formed at the entry side. The high drill size resulted in greater chip thickness and an increased built-up edge on the cutting tools.

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Comprehensive Research and Analysis of a Coated Machining Tool with a New TiAlN Composite Microlayer Using Magnetron Sputtering

Materials ◽

10.3390/ma14133633 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3633

Author(s):

Štefan Michna ◽

Iryna Hren ◽

Jan Novotný ◽

Lenka Michnová ◽

Václav Švorčík

Keyword(s):

Magnetron Sputtering ◽

Surface Defects ◽

Light And Electron Microscopy ◽

Cutting Tools ◽

Microstructural Characterization ◽

High Wear Resistance ◽

Drilling Process ◽

Cross Sectional ◽

Force Microscopy ◽

New Type

The application of thin monolayers helps to increase the endurance of a cutting tool during the drilling process. One such trendy coating is TiAlN, which guarantees high wear resistance and helps to “smooth out” surface defects. For this reason, a new type of weak TiAlN microlayer with a new composition has been developed and applied using the HIPIMs magnetron sputtering method. The aim of this study was to analyze surface-applied micro coatings, including chemical composition (EDX) and microstructure in the area of the coatings. Microstructural characterization and visualization of the surface structures of the TiAlN layer were performed using atomic force microscopy. To study the surface layer of the coatings, metallographic cross-sectional samples were prepared and monitored using light and electron microscopy methods. The microhardness of the test layer was also determined. Analyses have shown that a 2-to-4-micron thick monolayer has a microhardness of about 2500 HV, which can help increase the life of cutting tools.

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Change of the Properties of Steel Material of the Roller Cone Bit Due to the Influence of the Drilling Operational Parameters and Rock Properties

Energies ◽

10.3390/en13225949 ◽

2020 ◽

Vol 13 (22) ◽

pp. 5949

Author(s):

Jurij Šporin ◽

Tilen Balaško ◽

Primož Mrvar ◽

Blaž Janc ◽

Željko Vukelić

Keyword(s):

Structural Changes ◽

Simultaneous Thermal Analysis ◽

Rock Properties ◽

Drilling Process ◽

Drill Bit ◽

Operational Parameters ◽

Rock Materials ◽

Steel Material ◽

Drilling Parameters ◽

Bit Life

The breakdown of the drill bit or rapid decrease of the rate of penetration during the drilling process results in a delay in the progress of drilling. Scientists and engineers are increasingly focusing on research to extend the bit life and improve the drilling rate. In our work, “in situ” drilling parameters were monitored during the drilling process with the roller cone drill bit IADC 136, diameter 155.57 mm (6 1/8"). After drilling, the bit was thoroughly examined to determine the damage and wear that occurred during drilling. The following modern and standardized investigative methods were used: an analysis of rock materials and an analysis of micro and macrostructure materials of the roller cone bit. Analyses were carried out using optical and electron microscopy, a simultaneous thermal analysis of materials of drill bit, analysis of the chemical composition of materials of drill bit, and a determination of the geomechanical parameters of rock materials. The resulting wear, local bursts, and cracks were quantitatively and qualitatively defined and linked to the drilling regime and the rock material. The results of our investigation of the material of the roller cone bit can serve as a good base for the development of new steel alloys, which can resist higher temperatures and enable effective drilling, without structural changes of steel material.

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Dynamical properties about ultrasonic vibration assisted drilling of TiBw/TC4 composite

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405420968431 ◽

2020 ◽

pp. 095440542096843

Author(s):

Yong Feng ◽

Haoxiang Wang ◽

Min Zhang ◽

Zihao Zhu ◽

Xiaoyu Wang ◽

...

Keyword(s):

Ultrasonic Vibration ◽

Cutting Tools ◽

System Model ◽

Force Model ◽

Drilling Process ◽

Drilling Force ◽

Dry Cutting ◽

Analysis System ◽

The Stability ◽

Three Degree Of Freedom

TiBw / TC4 composite material was used as the machining object of Ultrasonic vibration assisted drilling (UVAD), the single directional three-degree-of-freedom dynamical system model was established. The dynamic signal test and analysis system was used for modal experiment to identify the parameters in the model. Under the condition of dry cutting, the drilling axial force and tool vibration in the drilling process are studied. The results showed that the maximum values of the predicted and measured axial drilling force were 412.5N and 439.6N respectively, and the error rate was 6.165%, which verified the reliability of the predicted axial drilling force model. For cutting tools, the average amplitudes of simulated vibration and measured vibration were 0.1124mm and 0.1151mm respectively, with a difference of 2.402%, and the overall trends were the same, which verifies the reliability of the dynamical model. Finally, the stability of drilling process was analyzed, and the frequency and amplitude of ultrasonic vibration were analyzed. The results show that in order to expand the unconditional stability region, it is more efficient to increase the amplitude than to increase the frequency.

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Mechanical and thermal properties of the glassy semiconductor chlorinated Se0 997As0 003 used as an X-ray imaging material

Canadian Journal of Physics ◽

10.1139/p89-124 ◽

1989 ◽

Vol 67 (7) ◽

pp. 686-693 ◽

Cited By ~ 13

Author(s):

S. O. Kasap ◽

S. Yannacopoulos

Keyword(s):

Thermal Properties ◽

Structural Changes ◽

Relaxation Times ◽

Thermal Relaxation ◽

Mechanical And Thermal Properties ◽

Debye Relaxation ◽

X Ray ◽

Temperature Range ◽

Glass Transformation ◽

X Ray Imaging

Mechanical and thermal properties of a typical X-ray imaging material amorphous Se0.997As0.003, chlorinated in the ppm range were investigated using thermal microhardness analysis (TμHA) and differential scanning calorimetry (DSC). The experiments were carried out over a temperature range encompassing the glass transformation to study the nature of structural changes controlling the mechanical and thermal properties. It is shown that the mechanical property microhardness when examined on an Itoh–Shishokin plot of log Vickers hardness number (VHN) vs. temperature (T) exhibits a hardness transition temperature, Tg*, in the glass transformation region. The rates of relaxation of the mechanical and thermal properties in the glass transformation region were studied by investigating the heating rate dependence of the glass transition temperatures, Tg* and Tg, defined empirically on the log VHN vs. T behavior and the DSC glass transformation endotherm, respectively. By applying the present thermoanalytical methods, it has proved possible to identify a typical Vogel–Tammann–Fulcher type of behavior in the mechanical and thermal relaxation times that correlates remarkably well with the viscosity–temperature data of M. Cukierman and D. R. Uhlmann (J. Non-Cryst. Solids, 12, 199 (1973)) as well as the dielectric loss experiments of M. Abkowitz, D. F. Pochan, and J. M. Pochan (J. Appl. Phys. 51, 1539 (1980)). The latter had previously exposed a Williams–Landel–Ferry relation for the Debye relaxation times in a-Se and a-Se: 1% As. It is therefore concluded that the behavior of mechanical, thermal, and dielectric properties of a-Se0997As0003 in the glass transformation region is inversely proportional to the viscosity, which in turn can be adequately described over a temperature range above ~30 °C by a Vogel expression.

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Simple Detection of Binding Events Using an Anchoring Transition of Liquid Crystals on the Immobilized oligoDNAs

MRS Proceedings ◽

10.1557/proc-0915-r03-25 ◽

2006 ◽

Vol 915 ◽

Author(s):

Hak-Rin Kim ◽

Min-Geon Choi ◽

Joo-Eun Kim ◽

Eui-Yul Choi ◽

Sang-Wook Oh ◽

...

Keyword(s):

Structural Changes ◽

Extinction Ratio ◽

Target Material ◽

Dna Chip ◽

Interface Condition ◽

Steric Interaction ◽

Optical Signals ◽

Simple Detection ◽

Novel Method ◽

Sophisticated Analysis

AbstractTo detect biological events, biosensors require a transducer part where specific biomolecular binding events at a bioreceptor part is converted to measurable quantitative signals. Currently, most of biosensors adopt a fluorescent or radioactive probing technique as a transducer. However, such approaches require expensive and sophisticated analysis procedures with laboratory-based equipment.In this work, we propose a novel method for optically detecting hybridization results in a deoxyribonucleic acid (DNA) chip using an anchoring transition of liquid crystal (LC) alignment. To investigate the effects of structural changes of DNA on the LC alignment, we used a functional substrate on which single-stranded oligonucleotide DNA (ssDNA) was selectively immobilized to a Biotin Chip substrate. In our experiment, we used a 19-mer oligoDNA or p53 tumor suppressor as a bioreceptor and its complementary partner oligoDNA as a target material.Before hybridization, surface nematic LC (NLC) molecules on the immobilized ssDNAs are homeotropically aligned by a steric interaction between the freely penetrated NLC molecules and the ssDNA. After hybridization, the penetration of the NLC molecules is hindered by the double strand DNA (dsDNA) due to their increased packing density. Such an interface condition makes the surface ordering of the NLC molecules very weak, as a result, the NLC in the bulk has a planar inhomogeneous orientation. Although hybridization events of the DNA and the subsequent molecular interaction between the immobilized DNA and the NLC molecules takes place within a layer whose thickness is in the tens of nm, such binding events can be communicated to the NLC bulk beyond a distance of tens of μm though the long-range elastic deformation of the NLC molecules. Thus, the hybridization event is converted to amplified optical signals via birefringent nature of the NLC between crossed polarizers. Our NLC-based DNA chip array showed that the extinction ratio of transmitted light depending on the hybridization results was approximately four, which could be read by the naked eye. Since such anchoring behaviors on the immobilized DNA are very similar to those on the conventional amphiphilic homeotropic surfactant of LCs, it is expected that quantitative analysis of hybridization events can be explored with our simple system.

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Unique thermodynamic relationships for Δf H o and Δf G o for crystalline inorganic salts. I. Predicting the possible existence and synthesis of Na2SO2 and Na2SeO2

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768112030686 ◽

2012 ◽

Vol 68 (5) ◽

pp. 511-527 ◽

Cited By ~ 8

Author(s):

Ángel Vegas ◽

Joel F. Liebman ◽

H. Donald Brooke Jenkins

Keyword(s):

High Pressure ◽

Solid State ◽

Alkali Metal ◽

Liquid Ammonia ◽

Structural Changes ◽

Target Material ◽

The Other ◽

Inorganic Salts ◽

Linear Relationships ◽

The Stability

The concept that equates oxidation and pressure has been successfully utilized in explaining the structural changes observed in the M 2S subnets of M 2SO x (x = 3, 4) compounds (M = Na, K) when compared with the structures (room- and high-pressure phases) of their parent M 2S `alloy' [Martínez-Cruz et al. (1994), J. Solid State Chem. 110, 397–398; Vegas (2000), Crystallogr. Rev. 7, 189–286; Vegas et al. (2002), Solid State Sci. 4, 1077–1081]. These structural changes suggest that if M 2SO2 would exist, its cation array might well have an anti-CaF2 structure. On the other hand, in an analysis of the existing thermodynamic data for M 2S, M 2SO3 and M 2SO4 we have identified, and report, a series of unique linear relationships between the known Δf H o and Δf G o values of the alkali metal (M) sulfide (x = 0) and their oxyanion salts M 2SO x (x = 3 and 4), and the similarly between M 2S2 disulfide (x = 0) and disulfur oxyanion salts M 2S2O x (x = 3, 4, 5, 6 and 7) and the number of O atoms in their anions x. These linear relationships appear to be unique to sulfur compounds and their inherent simplicity permits us to interpolate thermochemical data (Δf H o) for as yet unprepared compounds, M 2SO (x = 1) and M 2SO2 (x = 2). The excellent linearity indicates the reliability of the interpolated data. Making use of the volume-based thermodynamics, VBT [Jenkins et al. (1999), Inorg. Chem. 38, 3609–3620], the values of the absolute entropies were estimated and from them, the standard Δf S o values, and then the Δf G o values of the salts. A tentative proposal is made for the synthesis of Na2SO2 which involves bubbling SO2 through a solution of sodium in liquid ammonia. For this attractive thermodynamic route, we estimate ΔG o to be approximately −500 kJ mol−1. However, examination of the stability of Na2SO2 raises doubts and Na2SeO2 emerges as a more attractive target material. Its synthesis is likely to be easier and it is stable to disproportionation into Na2S and Na2SeO4. Like Na2SO2, this compound is predicted to have an anti-CaF2 Na2Se subnet.

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Analysis of the Performance of Drilling Operations for Improving Productivity

10.5772/intechopen.96497 ◽

2021 ◽

Author(s):

Majid Tolouei-Rad ◽

Muhammad Aamir

Keyword(s):

High Speed ◽

Cutting Tools ◽

High Speed Steel ◽

Dimensional Accuracy ◽

Vital Role ◽

Machining Process ◽

Drilling Process ◽

Single Shot ◽

Drilling Operations

Drilling is a vital machining process for many industries. Automotive and aerospace industries are among those industries which produce millions of holes where productivity, quality, and precision of drilled holes plays a vital role in their success. Therefore, a proper selection of machine tools and equipment, cutting tools and parameters is detrimental in achieving the required dimensional accuracy and surface roughness. This subsequently helps industries achieving success and improving the service life of their products. This chapter provides an introduction to the drilling process in manufacturing industries which helps improve the quality and productivity of drilling operations on metallic materials. It explains the advantages of using multi-spindle heads to improve the productivity and quality of drilled holes. An analysis of the holes produced by a multi-spindle head on aluminum alloys Al2024, Al6061, and Al5083 is presented in comparison to traditional single shot drilling. Also the effects of using uncoated carbide and high speed steel tools for producing high-quality holes in the formation of built-up edges and burrs are investigated and discussed.

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