(Invited) Novel Technique to Measure Thermal Diffusivity of Soft Crystal in Micro Scale

Anodic spark deposition (ASD) is a novel technique to deposit bioceramic films on the surface of titanium (Ti) and its alloys, and the films prepared with nano/micro scale pores are characterized by high-quality performance for dental implant. Among the process parameters, electrolyte provides a leading role owing to its vital influence not only on the films chemistry but also on the electrical conductivity of the circuit, which affects the film properties. In this study, titania porous films were synthesized by ASD and the effect of electrolytic temperature on microstructure and chemical composition of the films was studied. The results show that the electrolytic temperature could significantly influence the surface topography, thickness and chemical composition of the oxidation films produced by ASD and, therefore, determined the layered hydroapatite (HA) deposition as the other process parameters were fixed.

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Micro-scale thermal diffusivity measurements of banded spherulites of poly-(l-lactic acid) using a thermo-electric micro sensor

Thermochimica Acta ◽

10.1016/j.tca.2011.08.017 ◽

2012 ◽

Vol 532 ◽

pp. 148-151 ◽

Cited By ~ 6

Author(s):

Akihiro Orie ◽

Junko Morikawa ◽

Toshimasa Hashimoto

Keyword(s):

Lactic Acid ◽

Thermal Diffusivity ◽

Thermo Electric ◽

Micro Scale ◽

Diffusivity Measurements ◽

Banded Spherulites ◽

Micro Sensor

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Thermal diffusivity by laser intensity modulation method (LIMM-TD): a novel technique for the determination of thermal diffusivities and conductivities and its application to porous PZT and silica samples

IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control ◽

10.1109/tuffc.2007.587 ◽

2007 ◽

Vol 54 (12) ◽

pp. 2608-2616 ◽

Cited By ~ 5

Author(s):

Sidney Lang ◽

Erling Ringgaard ◽

Supasarote Muensit ◽

Xiaoqing Wu ◽

Jason Lashley ◽

...

Keyword(s):

Thermal Diffusivity ◽

Laser Intensity ◽

Intensity Modulation ◽

Modulation Method ◽

Novel Technique ◽

Thermal Diffusivities ◽

Porous Pzt

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Non-Destructive Investigation of Dispersion, Bonding, and Thermal Properties of Emerging Polymer Nanocomposites Using Close-Up Lens Assisted Infrared Thermography

MRS Advances ◽

10.1557/adv.2020.121 ◽

2020 ◽

Vol 5 (14-15) ◽

pp. 735-742

Author(s):

Ali Ashraf ◽

Nikhil Jani ◽

Francis Farmer ◽

Jennifer K. Lynch-Branzoi

Keyword(s):

Thermal Properties ◽

Thermal Diffusivity ◽

Polymer Nanocomposites ◽

Polymer Nanocomposite ◽

Thermal Imager ◽

Ir Camera ◽

Micro Scale ◽

Matrix Interaction ◽

Non Destructive ◽

Insight Into

AbstractPolymer nanocomposites possess unique sets of properties that make them suitable for different applications, including structural and flame-retardant material, electromagnetic wave reflector, sensors, thin film transistor, flexible display, and many more. The properties of these nanocomposite are dependent on nanofiller dispersion and bonding with polymer matrix (i.e. particle-matrix interaction). Thermography is a non-destructive method that may be used to gain insight into dispersion and particle-matrix interaction. Infrared (IR) radiation emitted from these nanomaterial polymer composite depends on the emissivity of the individual components. In addition, during flash heating and cooling, different thermal conductivity of components in the nanocomposite can influence pixel intensity differently in the IR image or video being captured. We have used an economical mid wavelength IR camera Fluke RSE600 equipped with a close-up macro lens and algorithm based on MATLAB image processing toolbox to analyse dispersion, voids and thermal diffusivity of patented graphene polymer nanocomposite materials (G-PMC) in micro-scale. These G-PMCs can act as a standard material to determine the potential of our IR thermography technique due to their homogeneity and lack of impurity due to unique fabrication process. Thermal diffusivity and dispersion of nanoparticles in our G-PMCs was estimated after irradiation with a xenon flash lamp by spatially mapping transient IR radiations from different G-PMCs using the Fluke RSE600 thermal imager. Results from thermography experiments were compared with scanning electron microscope (SEM) and Raman spectroscopy results. Micro-scale thermography was able to detect millimetre scale thermal diffusivity variation in the injection molded G-PMC samples and relate it to change in dispersion of nanofillers, unlike SEM and Raman, where micro-scale measurements could not determine the reason behind millimetre scale property variation. We believe this low cost, fast, micro-scale, non-destructive technique will provide valuable insight into functional polymer nanocomposite fabrication and corresponding electrical and thermal properties.

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Time-Resolved and Micro-Scale Measurement of Thermal Property for Intermolecular Dynamics Using an Infrared Laser

ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference, Volume 2 ◽

10.1115/ht2007-32918 ◽

2007 ◽

Author(s):

Masahiro Motosuke ◽

Yuji Nagasaka ◽

Shinji Honami

Keyword(s):

Thermal Diffusivity ◽

Thermal Property ◽

Rayleigh Scattering ◽

Control Technique ◽

Scattering Method ◽

Time Resolved ◽

Infrared Wavelength ◽

Micro Scale ◽

Forced Rayleigh Scattering Method ◽

Intermolecular Association

This paper describes a time-resolved measurement of thermal property in microscale during reaction process of a polymer by using an infrared (IR) laser. Polymer and gel-like material, so-called macromolecules, have diversity in its structure and intermolecular association, and recent development of measurement and control technique in micro- and nano-scale has open up new possibilities for the property design in the materials, including the control of thermophysical properties. The heat conduction process in macromolecules is affected by the internal structure or intermolecular association of the material. Thus, the intermolecular dynamics of polymer can be reflected in time-resolved information of the thermal conductivity or thermal diffusivity. A measurement system of the thermal diffusivity in time-resolved and non-contact manner based on the forced Rayleigh scattering method (FRSM) has been developed. This system can be applied for a changing process of a wide variety of polymer material because of employing a CO2 laser with the infrared wavelength of 10.6 μm. Also, it is possible to measure micro-scale property. In the present study, the measurement area is set at 500 μm in diameter. By using the IR-FRSM system, an investigation of the relationship between intermolecular dynamics of macromolecules and energy transfer can be conducted through the time-resolved data of the thermal diffusivity. As samples, crosslinking processes of a polysaccharide aqueous solution and an ultraviolet curable polymer are measured; variations in molecular interactions caused by hydrogen and covalent bonding occur, respectively. Time evolution of the measured thermal property from the IR-FRSM system clearly indicates the difference in bonding modes of macromolecules. According to the time-resolved measurement results, the validity of the IR-FRSM for a versatile instrument of intermolecular dynamics of macromolecules is demonstrated.

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Micro-Scale Fatigue Damage Assessment of CFRP Laminates Using Lock-in Thermography

Engineering Proceedings ◽

10.3390/engproc2021008002 ◽

2021 ◽

Vol 8 (1) ◽

pp. 2

Author(s):

Ryohei Fujita ◽

Kotaro Katsukura ◽

Hosei Nagano

Keyword(s):

Thermal Diffusivity ◽

Fatigue Damage ◽

Damage Assessment ◽

Assessment Method ◽

Thermal Diffusivity Measurement ◽

Cfrp Laminates ◽

Micro Scale ◽

Reinforced Plastics ◽

Diffusivity Measurement ◽

Lock In

This study proposes a new micro-scale damage assessment method of laminated carbon fiber-reinforced plastics based on the thermal diffusivity measurement. This measurement was conducted by the laser-spot-periodic-heating method using lock-in thermography. Measured samples were subjected to the tension fatigue test at a relatively low load and high cycle. As a result, the thermal diffusivity showed a decreasing trend with an increase in the load cycles. It was shown that this method can detect the effect of the minute fatigue damage at a level that cannot be seen with a microscope.

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