Environmental friendly cutting fluids and cooling techniques in machining: a review

Atmospheric-pressure plasmas (APPs) have attracted great interest and have been widely applied in biomedical applications, as due to their non-thermal and reactive properties, they interact with living tissues, cells and bacteria. Various types of plasma sources generated at atmospheric pressure have been developed to achieve better performance in specific applications. This article presents an overview of the general characteristics of APPs and a brief summary of their biomedical applications, and reviews a wide range of these sources developed for biomedical applications. The plasma sources are classified according to their power sources and cover a wide frequency spectrum from dc to microwaves. The configurations and characteristics of plasma sources are outlined and their biomedical applications are presented.

https://iopscience.iop.org/article/10.1088/0963-0252/21/4/043001/pdf

Atmospheric-pressure plasma sources for biomedical applications

The generalization of the Local Density Approximation (LDA) method for the systems with strong Coulomb correlations is presented which gives a correct description of the Mott insulators. The LDA+U method is based on the model hamiltonian approach and allows to take into account the non-sphericity of the Coulomb and exchange interactions. parameters. Orbital-dependent LDA+U potential gives correct orbital polarization and corresponding Jahn-Teller distortion. To calculate the spectra of the strongly correlated systems the impurity Anderson model should be solved with a many-electron trial wave function. All parameters of the many-electron hamiltonian are taken from LDA+U calculations. The method was applied to NiO and has shown good agreement with experimental photoemission spectra and with the oxygen Kα X-ray emission spectrum.

http://absimage.aps.org/image/MAR06/MWS_MAR06-2005-007233.pdf

First-principles calculations of electronic structure and spectra of strongly correlated systems: the LDA+U method

Study on microstructure, mechanical properties and machinability of efficiently additive manufactured AISI 316L stainless steel by high-power direct laser deposition

Aluminum Metal Matrix Composites (MMCs) sought over other conventional materials in the field of aerospace, automotive and marine applications owing to their excellent improved properties. These materials are of much interest to the researchers from few decades. These composites initially replaced Cast Iron and Bronze alloys but owing to their poor wear and seizure resistance, they were subjected to many experiments and the wear behavior of these composites were explored to a maximum extent and were reported by number of research scholars for the past 25 years. In this paper an attempt has been made to consolidate some of the aspects of mechanical and wear behavior of Al-MMCs and the prediction of the Mechanical and Tribological properties of Aluminum MMCs.

/pdf/mechanical-and-tribological-behavior-of-particulate-4x05huiioi.pdf

Mechanical and Tribological Behavior of Particulate Reinforced Aluminum Metal Matrix Composites – a review

Moisture in the hydrophilic material may potentially influence the plasma treatment effect. In order to understand how moisture absorbed into PVA affects the result of plasma treatment to the polymer, atactic poly(vinyl alcohol) (PVA) films with moisture regain (MR) of 2.5%, 9.3% and 78.3% corresponding to 10%, 65% and 98% relative humidity (RH), respectively were exposed to atmospheric pressure plasma jet. Another group was annealed at 140 °C for 20 min to discern the thermal effects from those due to plasma treatment. Scanning electron microscope (SEM) showed lamellae crystal structures were on the surface of the films with 65% and 98% RH, while some bubbles or salt grains appeared on the surface of film with 10% RH and the annealed film respectively. X-ray photoelectron spectroscopy (XPS) analysis indicated that oxygen concentration increased for plasma treated films with 65% and 98% RH and decreased for that with 10% RH. X-ray diffraction analysis (XRD) shows an increase in crystallinity in all the plasma treated films. It was found that the solubility of all the treated films was decreased, especially for the plasma treated film under 98% RH which is nearly insoluble in water at 50 °C for 20 min.

Influence of absorbed moisture on solubility of poly(vinyl alcohol) film during atmospheric pressure plasma jet treatment

The influence of moisture on atmospheric pressure plasma etching of PA6 films

The cutting force is one of the main factors that influence the processing quality of fiber-reinforced polymer composites (FRPs). However, since the material removal mechanics of composites are quite different from those of metals, the cutting mechanisms of metals cannot be directly used for orthogonal cutting of composites. This paper aims to develop a novel force prediction model without the need to run any experiments. The deformation of fiber and the support of surrounding matrix are analyzed based on the minimum potential energy principle and the dynamic equilibrium. A force prediction model of FRP cutting is obtained for fiber orientations ranging from 0 to 90° + γ. The relevant experiments conducted showed the validity of the proposed model. The influence of rake angle and clearance angle on cutting force is analyzed.

Modeling and analysis of force prediction in milling process of unidirectional fiber reinforced polymer composites

A high strength AlSi10Mg alloy fabricated by laser powder bed fusion with addition of AlTiCB master alloy powders

In the aviation industry, flexural distortion of thin-walled aeronautic parts after machining processes is inevitable, especially for high-strength aluminum alloy. To satisfy the accuracy requirement for subsequent assembly processes, the distorted parts have to be corrected. Bilateral rolling operation has been proved to be an effective method for correcting the flexural distortion. However, this method is generally based on trial and error, and the quality of distortion correcting cannot be guaranteed. To solve this problem, finite element method (FEM) was first adopted to investigate the distortion feature after bilateral rolling process for T-shaped structures. The relationship between processing parameters and maximum deflection was then studied. An equivalent bending moment method was proposed to represent the effects of bilateral rolling on micro-plastic deformation and residual stresses. Besides, a theoretical model was established for distortion prediction. Furthermore, based on simulation results, the calculation formula of the equivalent load was deduced. Finally, the theoretical model and the equivalent bending moment method were verified by rolling correction experiments, which were used to calculate the rolling correcting load (rolling depth). The results show that the average reduction rate of deflection is 73.5%. This paper provides an effective theoretical model for predicting the correction load in rolling correction process for thin-walled aeronautic parts.

Jie Sun

Papers

Influence of absorbed moisture on solubility of poly(vinyl alcohol) film during atmospheric pressure plasma jet treatment

The influence of moisture on atmospheric pressure plasma etching of PA6 films

Modeling and analysis of force prediction in milling process of unidirectional fiber reinforced polymer composites

A high strength AlSi10Mg alloy fabricated by laser powder bed fusion with addition of AlTiCB master alloy powders

A theoretical model for load prediction in rolling correction process of thin-walled aeronautic parts