scholarly journals Laser Transmission Welding of Aluminum Film Coated With Heat Sealable Co-Polyester Resin With Polypropylene Films For Applications In Food & Drug Packaging

2021 ◽  
Author(s):  
Annamaria Gisario ◽  
Clizia Aversa ◽  
Massimiliano Barletta ◽  
Stefano Natali ◽  
Francesco Veniali
Keyword(s):  
Food Packaging ◽  
Polyester Resin ◽  
Scanning Speed ◽  
Aluminum Film ◽  
Beam Power ◽  
Aluminum Films ◽  
Drug Packaging ◽  
Laser Joining ◽  
Wide Range ◽  
Joining Process

Abstract The present work deals with the high-power diode laser joining process of aluminum films coated with a polyester resin with polypropylene (PP) films. The first part of the work focused on analyzing the coating process of aluminum films with a polyester resin, using an automatic applicator. The second part of the work was focused on the analysis of the laser joining process of coated aluminum films with plastic counterparts made of PP. Different thicknesses and colors of the PP parts were tested in order to analyze the joining process under a wide range of different conditions. The experimental plan involved the study of the influence of the laser joining parameters, in particular the scanning speed and beam power, on the joints. The joints between aluminum and PP films were subsequently tested by means of tensile and peel-off tests. The results allowed the detection of the best processing conditions, stating the high potential of laser systems in the joining process of aluminum and PP films for food packaging applications.

Laser joining of aluminum film coated with vinylic resin and plastic/bioplastic films for applications in food packaging

2021 ◽  
Vol 142 ◽  
pp. 107237
Author(s):  
A. Gisario ◽  
C. Aversa ◽  
M. Barletta ◽  
S. Natali ◽  
F. Veniali
Keyword(s):  
Food Packaging ◽  
Aluminum Film ◽  
Laser Joining

Assessment of mechanical and biocompatible performance of ultra-large nitinol endovascular devices fabricated via a low-energy laser joining process

2021 ◽  
pp. 088532822110195
Author(s):  
Moataz Elsisy ◽  
Mahdis Shayan ◽  
Yanfei Chen ◽  
Bryan W Tillman ◽  
Catherine Go ◽  
...  
Keyword(s):  
Laser Power ◽  
In Vitro Study ◽  
Spot Size ◽  
Laser Joining ◽  
Study Results ◽  
Energy Laser ◽  
Joining Process ◽  
Endovascular Devices ◽  
Low Energy Laser

Nitinol is an excellent candidate material for developing various self-expanding endovascular devices due to its unique properties such as superelasticity, biocompatibility and shape memory effect. A low-energy laser joining technique suggests a high potential to create various large diameter Nitinol endovascular devices that contain complex geometries. The primary purpose of the study is to investigate the effects of laser joining process parameters with regard to the mechanical and biocompatible performance of Nitinol stents. Both the chemical composition and the microstructure of the laser-welded joints were evaluated using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). In vitro study results on cytotoxicity demonstrated that the joining condition of 8 Hz frequency and 1 kW laser power showed the highest degree of endothelial cell viability after thermal annealing in 500°C for 30 min. Also, in vitro study results showed the highest oxygen content at 0.9 kW laser power, 8 Hz frequency, and 0.3 mm spot size after the thermal annealing. Mechanical performance test results showed that the optimal condition for the highest disconnecting force was found at 1 Hz frequency and 1 kW power with 0.6 mm spot size. Two new endovascular devices have been fabricated using the optimized laser joining parameters, which have demonstrated successful device delivery and retrieval, as well as acute biocompatibility.

Optical and Mechanical Properties of Aluminum Film Deposited on Glass Substrate

2010 ◽  
Vol 297-301 ◽  
pp. 444-449 ◽  
Author(s):  
Shiuh Chuan Her ◽  
Yi Hsia Wang
Keyword(s):  
Wavelength Region ◽  
Aluminum Film ◽  
Surface Topology ◽  
Aluminum Films ◽  
Glass Substrates ◽  
Atomic Force ◽  
Environmental Test ◽  
Optical Applications ◽  
Optical And Mechanical Properties ◽  
Al Thin Film

The aluminum film with high reflectivity and low absorption in the visible wavelength region has been widely used in optical applications. In this investigation, aluminum films were prepared on glass substrates by electron-beam vapor deposition. The reflectivity of the Al thin film was measured by a Perkin-Elmer Lambda spectrophotometer in the wavelength region of 450-680 nm. The experimental measurements of reflectivity were validated with the numerical results using the Essential Macleod software. The surface topology and microstructure of the film were examined by means of atomic force microscope (AFM). The effects of the temperature and humidity on the reflectivity of the Al film were examined by the environmental test. Nanoindentation tests were employed to determine the hardness and Young’s modulus of the film. The measured hardness of the Al thin films were found to depend on the penetration depth.

scholarly journals Emergence of an invariant representation of texture in primate somatosensory cortex

2019 ◽  
Author(s):  
Justin D. Lieber ◽  
Sliman J. Bensmaia
Keyword(s):  
Cortical Neurons ◽  
Rhesus Macaques ◽  
Scanning Speed ◽  
Nerve Fibers ◽  
Invariant Representation ◽  
Major Function ◽  
Neural Representations ◽  
Wide Range ◽  
Sensory Modalities ◽  
Exploratory Movements

ABSTRACTA major function of sensory processing is to achieve neural representations of objects that are stable across changes in context and perspective. Small changes in exploratory behavior can lead to large changes in signals at the sensory periphery, thus resulting in ambiguous neural representations of objects. Overcoming this ambiguity is a hallmark of human object recognition across sensory modalities. Here, we investigate how the perception of tactile texture remains stable across exploratory movements of the hand, including changes in scanning speed, despite the concomitant changes in afferent responses. To this end, we scanned a wide range of everyday textures across the fingertips of Rhesus macaques at multiple speeds and recorded the responses evoked in tactile nerve fibers and somatosensory cortical neurons. We found that individual cortical neurons exhibit a wider range of speed-sensitivities than do nerve fibers. The resulting representations of speed and texture in cortex are more independent than are their counterparts in the nerve and account for speed-invariant perception of texture. We demonstrate that this separation of speed and texture information is a natural consequence of previously described cortical computations.

scholarly journals Porosity Elimination in Modified Direct Laser Joining of Ti6Al4V and Thermoplastics Composites

2019 ◽  
Vol 9 (3) ◽  
pp. 411 ◽  
Author(s):  
Haipeng Wang ◽  
Yang Chen ◽  
Zaoyang Guo ◽  
Yingchun Guan
Keyword(s):  
Glass Fiber ◽  
Fracture Strength ◽  
Joint Strength ◽  
Surface Texturing ◽  
Practical Applications ◽  
Laser Joining ◽  
Glass Fiber Reinforced ◽  
Hybrid Joints ◽  
Direct Laser ◽  
Joining Process

Hybrid lightweight components with strong and reliable bonding qualities are necessary for practical applications including in the automotive and aerospace industries. The direct laser joining method has been used to produce hybrid joints of Ti6Al4V and glass fiber reinforced polyamide (PA66-GF30). Prior to the laser joining process, a surface texturing treatment is carried out on Ti6Al4V to improve joint strength through the formation of interlock structures between Ti6Al4V and PA66-GF30. In order to reduce the generated micro-pores in Ti6Al4V-PA66-GF30 joints, a modified laser joining method has been proposed. Results show that only very few small micro-pores are generated in the joints produced by the modified laser joining method, and the fracture strength of the joints is significantly increased from 13.8 MPa to 41.5 MPa due to the elimination of micro-pores in the joints.

Formation of Intermetallics and Grain Boundary Diffusion in Cu-Al and Au-Al Thin Film Couples

1981 ◽  
Vol 10 ◽  
Author(s):  
J. M. Vandenberg ◽  
F. J. A. Den Broeder ◽  
R. A. Hamm
Keyword(s):  
Thin Film ◽  
Hexagonal Phase ◽  
Interface Reaction ◽  
Aluminum Film ◽  
Temperature Dependent ◽  
X Ray ◽  
Wide Range ◽  
Al Thin Film ◽  
Rich Side

An in situ annealing X-ray study was applied to Cu-Al thin film couples over a wide range of copper-to-aluminum film ratios. This new technique, which has been previously described for a study on the Au-Al thin film system, enables us to make a temperature-dependent photographic X-ray analysis. The present study indicated that only a limited number of the wide variety of bulk phases form in the Cu-Al thin film interface, while some of these phases in the interface are transient. In the transient stages of the interface reaction, the f.c.c.-ordered phase β-Cu3A1 grows over the entire range of copper-to-aluminum film ratios after the first nucleation of CuA12, indicating a two-step nucleation reaction. On the aluminum-rich side, this phase transforms to a new ordered hexagonal phase β′. It could be interpreted as a superlattice of the metastable hexagonal ω phase occurring in zirconium-based alloys. The end phases are CuA1 and CuAl2.

On-Line Process Control Compositional Analysis of Aluminum Films Containing a Low Percentage of Copper

1971 ◽  
Vol 15 ◽  
pp. 539-547
Author(s):  
G. H. Glade ◽  
J. M. Matthews ◽  
F. R. Titcomb
Keyword(s):  
Process Control ◽  
Interconnection Networks ◽  
Semiconductor Device ◽  
Compositional Analysis ◽  
Aluminum Film ◽  
Portable Instrument ◽  
Aluminum Films ◽  
On Line ◽  
Line Process ◽  
Control Application

Aluminum film conducting stripes are widely used for semiconductor device interconnection networks. The addition of a low percentage of copper significantly increases their life. Composition must be controlled to maintain product quality.The paper discusses various methods used to analyze the copper composition in the aluminum films, and adaptation of one of these methods for process control application. A portable instrument designed for field use was adapted for use as an on-line instrument.

Experimental Study of Micromachining on Borosilicate Glass Using CO2 Laser

2020 ◽  
Vol 143 (5) ◽  
Author(s):  
Vishnu Vardhan Posa ◽  
Murali Sundaram
Keyword(s):  
Laser Scanning ◽  
Laser Energy ◽  
Removal Rate ◽  
Scanning Speed ◽  
Machining Process ◽  
Laser Machining ◽  
Glass Work ◽  
Workpiece Material ◽  
Laser Parameters ◽  
Wide Range

Abstract Laser beam machining (LBM) is a versatile process that can shape a wide range of engineering materials such as metals, ceramics, polymers, and composite materials. However, machining of glass materials by LBM is a challenge as most of the laser energy is not absorbed by the surface. In this study, an attempt has been made to increase the absorptivity of the glass material by using a coating on the surface of the material. Glass has been used in this study because of its extensive applications in the micro-opto-electro-mechanical systems. The optimal machining depends on both laser parameters and properties of the workpiece material. There are number of laser parameters that can be varied in the laser machining process. It is difficult to find optimal laser parameters due to the mutual interaction of laser parameters. A statistical study based on design of experiment (DoE) has been made to study the effect of coating and parameters like laser power, laser scanning speed, angle of inclination of the workpiece on depth of the slot, width of the slot, aspect ratio, and material removal rate (MRR) in the laser machining process using 2k factorial design and analysis of variance (ANOVA). On an average, four times increase in depth of the slot, two times increase in width of the slot and seven times increase in the MRR were observed in the glass samples with coating when compared to uncoated glass work samples.

Simulation-Based Process Optimization of Metallic Additive Manufacturing Under Uncertainty

2019 ◽  
Author(s):  
Zhuo Wang ◽  
Pengwei Liu ◽  
Zhen Hu ◽  
Lei Chen
Keyword(s):  
Additive Manufacturing ◽  
Robust Design ◽  
Simulation Models ◽  
Scanning Speed ◽  
Parameters Optimization ◽  
Optimization Under Uncertainty ◽  
Data Driven ◽  
Robust Design Optimization ◽  
Beam Power ◽  
Noise Factors

Abstract The presence of various uncertainty sources in metal-based additive manufacturing (AM) process prevents producing AM products with consistently high quality. Using electron beam melting (EBM) of Ti-6A1-4V as an example, this paper presents a data-driven framework for process parameters optimization using physics-informed computer simulation models. The goal is to identify a robust manufacturing condition that allows us to constantly obtain equiaxed materials microstructures under uncertainty. To overcome the computational challenge in the robust design optimization under uncertainty, a two-level data-driven surrogate model is constructed based on the simulation data of a validated high-fidelity multi-physics AM simulation model. The robust design result, indicating a combination of low preheating temperature, low beam power and intermediate scanning speed, was acquired enabling the repetitive production of equiaxed-structure products as demonstrated by physics-based simulations. Global sensitivity analysis at the optimal design point indicates that among the studied six noise factors, specific heat capacity and grain growth activation energy have largest impact on the microstructure variation.

A Neutron Amplifier: Prospects for Reactor-Based Waste Transmutation

2004 ◽  
Author(s):  
Anatoly Blanovsky
Keyword(s):  
Neutron Source ◽  
Power Distribution ◽  
Wave Model ◽  
System Size ◽  
Reverse Direction ◽  
Fast Neutrons ◽  
Beam Power ◽  
Primary System ◽  
Pressurized Water ◽  
Wide Range

A design concept and characteristics for an epithermal breeder controlled by variable feedback and external neutron source intensity are presented. By replacing the control rods with neutron sources, we could maintain good power distribution and perform radioactive waste burning in high flux subcritical reactors (HFSR) that have primary system size, power density and cost comparable to a pressurized water reactor (PWR). Another approach for actinide transmutation is a molten salt subcritical reactor proposed by Russian scientists. To increase neutron source intensity the HFSR is divided into two zones: a booster and a blanket with solid and liquid fuels. A neutron gate (absorber and moderator) imposed between two zones permits fast neutrons from the booster to flow to the blanket. Neutrons moving in the reverse direction are moderated and absorbed in the absorber zone. In the HFSR, neptunium-plutonium fuel is circulated in the booster and blanket, and americium-curium in the absorber zone and outer reflector. Use of a liquid actinide fuel permits transport of the delayed-neutron emitters from the blanket to the booster, where they can provide additional neutrons (source-dominated mode) or all the necessary excitation without an external neutron source (self-amplifying mode). With a blanket neutron multiplication gain of 20 and a booster gain of 50, an external neutron source rate of at least 1015 n/s (0.7MW D-T or 2.5MW electron beam power) is needed to control the HFSR that produces 300MWt. Most of the power could be generated in the blanket that burns about 100 kg of actinides a year. The analysis takes into consideration a wide range of HFSR design aspects including the wave model of observed relativistic phenomena, plant seismic diagnostics, fission electric cells (FEC) with a multistage collector (anode) and layered cathode.

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