Measuring Method of Material Constants Using a Laser Scanning Micrometer at High Temperature

2000 ◽  
Vol 2000 (0) ◽  
pp. 291-292
Author(s):  
Kana KAMITSUBO ◽  
Hiroaki ISONO ◽  
Katsuhiko YASUDA ◽  
Koichiro KIHARA ◽  
Toshio SUGIBAYASHI
Keyword(s):  
High Temperature ◽  
Laser Scanning ◽  
Measuring Method ◽  
Material Constants

Two-Dimensional Transient Heat Transfer Model for High-Temperature Laser-Scanning Confocal Microscopy

2021 ◽  
Author(s):  
Dasith Liyanage ◽  
Suk-Chun Moon ◽  
Ajith S. Jayasekare ◽  
Abheek Basu ◽  
Madeleine Du Toit ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Phase Transformation ◽  
High Temperature ◽  
Laser Scanning ◽  
Laser Scanning Confocal Microscopy ◽  
Transfer Model ◽  
Two Dimensional ◽  
Scanning Confocal Microscopy ◽  
Solid Liquid Interface ◽  
Solid Liquid

Abstract High-temperature laser-scanning confocal microscopy (HT-LSCM) has proven to be an excellent experimental technique through in-situ observations of high temperature phase transformation to study kinetics and morphology using thin disk steel specimens. A 1.0 kW halogen lamp, within the elliptical cavity of the HT-LSCM furnace radiates heat and imposes a non-linear temperature profile across the radius of the steel sample. This local temperature profile when exposed at the solid/liquid interface determines the kinetics of solidification and phase transformation morphology. A two-dimensional numerical heat transfer model for both isothermal and transient conditions is developed for a concentrically solidifying sample. The model can accommodate solid/liquid interface velocity as an input parameter under concentric solidification with cooling rates up to 100 K/min. The model is validated against a commercial finite element analysis software package, Strand7, and optimized with experimental data obtained under near-to equilibrium conditions. The validated model can then be used to define the temperature landscape under transient heat transfer conditions.

The Application of 3D Laser Scanning Method in the Measurement of Pressure Vessel

2017 ◽  
Vol 865 ◽  
pp. 595-598
Author(s):  
Hui Zeng Yin ◽  
Xin Wei Yang ◽  
Rui Lan Tian ◽  
Xiu Zhi Sui
Keyword(s):  
Pressure Vessel ◽  
Point Cloud ◽  
Laser Scanning ◽  
Convex Surface ◽  
Measuring Method ◽  
Point Cloud Data ◽  
3D Laser Scanning ◽  
Scanning Method ◽  
Cloud Data ◽  
Dangerous Goods

Pressure vessel is widely used in the industrial engineering. Many materials in pressure vessel are inflammable and explosive dangerous goods. If the accident happens, great harm will be done to the lives and properties of people. Some common methods for studying pressure vessel have obvious drawbacks. 3D laser scanning method uses non-contact measuring method and can directly obtain the point cloud data of the mass surface which can be used to reconstruct any convex surface. According to the advantages of 3D laser scanning method, in this paper, it is introduced to measure the dimensions of flanges in pressure vessel. The experimental results obtained have little errors, which certify that 3D laser scanning method can be used to measure the dimensions of flanges and further study the characteristics of pressure vessel.

scholarly journals Experimental Study on the Behavior of TiN and Ti2O3 Inclusions in Contact with CaO‐Al2O3‐SiO2‐MgO Slags

Scanning ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
S. K. Michelic ◽  
C. Bernhard
Keyword(s):  
Experimental Study ◽  
High Temperature ◽  
Stainless Steels ◽  
Laser Scanning ◽  
Laser Scanning Confocal Microscopy ◽  
Dissolution Behavior ◽  
Inclusion Removal ◽  
Scanning Confocal Microscopy ◽  
Effective Removal ◽  
Final Steel

TiN and Ti2O3 are the predominant inclusion types in Ti-alloyed ferritic chromium stainless steels. In order to ensure the required steel cleanness level, an effective removal of such inclusions in the slag during secondary metallurgy is essential. This inclusion removal predominantly takes place via dissolution of the inclusion in the slag. The dissolution behavior of TiN and Ti2O3 in CaO-SiO2-Al2O3-MgO slags as well as their agglomeration behavior in the liquid steel is investigated using High Temperature Laser Scanning Confocal Microscopy and Tammann Furnace experiments. Thermodynamic calculations are performed using FactSage 7.0. The behavior of TiN is observed to be completely different to that of oxides. Ti2O3 dissolves quickly in slags, and its dissolution behavior is comparable to that of other already well examined oxides. In contrast, TiN shows a very intense gas reaction which is attributed to the release of nitrogen during contact with slag. Slags with higher SiO2 content show a significantly higher ability for the dissolution of TiN as compared to Al2O3-rich slags. The gas reaction is found to also significantly influence the final steel cleanness. Despite the easy absorption of TiN in the slag, the formed nitrogen supports the formation of pinholes in the steel.

EVALUATION OF THE PERFORMANCE OF ELECTROLESS Ni–B COATED BRASS CONTACTS UNDER FRETTING CONDITIONS

2008 ◽  
Vol 15 (04) ◽  
pp. 443-452 ◽  
Author(s):  
T. S. N. SANKARA NARAYANAN ◽  
YOUNG WOO PARK ◽  
KANG YONG LEE
Keyword(s):  
High Temperature ◽  
Contact Resistance ◽  
Laser Scanning ◽  
Low Frequency ◽  
Surface Profile ◽  
Oxidation Products ◽  
Wear Depth ◽  
Scanning Microscope ◽  
Metallic Particles ◽  
Electroless Ni

The performance of electroless (EL) Ni – B coated brass contacts under fretting conditions was evaluated. The contact resistance of EL Ni – B coated brass contact was measured as a function of fretting cycles. The surface profile and wear depth of the fretted zone were measured using laser scanning microscope. The study reveals that EL Ni – B coated contacts exhibit better performance under fretting conditions. However, at conditions which are prone for severe oxidation such as, low frequency (3 Hz) or high temperature (155°C), EL Ni – B coated contacts fail to exhibit a better stability. The quick removal of the oxide film by fretting motion, rapid oxidation of the fresh metallic particles and trapping of the oxidation products in the remaining coating, cause the contact resistance to increase to unacceptable levels at such conditions. The study concludes that EL Ni – B coating is not a suitable choice for connector contacts that could experience fretting under highly oxidizing conditions.

Growth Characteristic and Fracture Toughness of Laser Rapidly Solidified Al2O3/YAG/ZrO2 Ceramic Eutectic In Situ Composite

2008 ◽  
Vol 33-37 ◽  
pp. 495-500
Author(s):  
Hai Jun Su ◽  
Jun Zhang ◽  
Lin Liu ◽  
Heng Zhi Fu
Keyword(s):  
Fracture Toughness ◽  
High Temperature ◽  
Laser Scanning ◽  
Growth Characteristic ◽  
Lamellar Microstructure ◽  
Eutectic Growth ◽  
Oxide Ceramic ◽  
Quick Method ◽  
Rapidly Solidified

Directionally solidified oxide ceramic eutectic composites with superior strength, oxidation resistance, creep resistance, structural stability and low sensitivity to crack at high temperature have aroused much attention in recent years, and various preparation techniques have been developed. In situ fabrication of ceramic eutectic composites by laser rapid solidification is a cheap and quick method compared to conventional multi-step fabrication methods of fiber reinforced composites for high temperature use. In this paper, Al2O3/YAG/ZrO2 ternary eutectics are rapidly prepared from melt by directional solidification using laser zone remelting technique, the growth characteristic and fracture toughness are investigated. The results show that: (1) Laser rapidly solidified Al2O3/YAG/ZrO2 ceramic eutectic in situ composite presents a fine interpenetrating network structure, in which Al2O3, YAG and ZrO2 phases are continually interconnected and finely coupled without pores, colonies and grain boundaries between interfaces. (2) Laser scanning rate and power density strongly affect the eutectic growth. With the processing parameters adjusted properly, the eutectic shows homogeneous and coupled lamellar microstructure. The characteristic dimensions of the microstructure are around 2~3 1m for Al2O3 and YAG phases, and around 0.2~1 1m for ZrO2 phases, respectively. (3) The hardness and fracture toughness of the rapidly solidified Al2O3/YAG/ZrO2 eutectic are 16.7 GPa and 8.0 MPa.m1/2, respectively.

scholarly journals In Situ Mo(Si,Al)2-Based Composite through Selective Laser Melting of a MoSi2-30 wt.% AlSi10Mg Mixture

Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3720 ◽  
Author(s):  
Tatevik Minasyan ◽  
Sofiya Aydinyan ◽  
Ehsan Toyserkani ◽  
Irina Hussainova
Keyword(s):  
High Temperature ◽  
Selective Laser Melting ◽  
Laser Power ◽  
Laser Scanning ◽  
Scanning Speed ◽  
Laser Melting ◽  
Structural Applications ◽  
Laser Scanning Speed ◽  
Fusion Approach

The laser power bed fusion approach has been successfully employed to manufacture Mo(Si,Al)2-based composites through the selective laser melting of a MoSi2-30 wt.% AlSi10Mg mixture for high-temperature structural applications. Composites were manufactured by leveraging the in situ reaction of the components during printing at 150–300 W laser power, 500–1000 mm·s−1 laser scanning speed, and 100–134 J·mm−3 volumetric energy density. Microcomputed tomography scans indicated a negligible induced porosity throughout the specimens. The fully dense Mo(Si1-x,Alx)2-based composites, with hardness exceeding 545 HV1 and low roughness for both the top (horizontal) and side (vertical) surfaces, demonstrated that laser-based additive manufacturing can be exploited to create unique structures containing hexagonal Mo(Si0.67Al0.33)2.

scholarly journals Tribological Properties of Mo-Si-B Alloys Doped with La2O3 and Tested at 293–1173 K

Materials ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 2011 ◽  
Author(s):  
Wenhu Li ◽  
Taotao Ai ◽  
Hongfeng Dong ◽  
Guojun Zhang
Keyword(s):  
High Temperature ◽  
Tribological Properties ◽  
Laser Scanning ◽  
Wear Behavior ◽  
Surface Oxidation ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Low Friction ◽  
Friction Coefficients ◽  
Wear Rates

According to the stoichiometric ratios of Mo-10Si-7B, Mo-12Si-8.5B, Mo-14Si-9.8B, and Mo-25Si-8.5B, some new Mo-Si-B alloys doped with 0.3 wt % lanthanum (III) oxide (La2O3) were prepared via liquid-liquid (L-L) doping, mechanical alloying (MA), and hot-pressing (HP) sintering technology. The phase-composition and microstructure were investigated by X-ray diffraction (XRD) and scanning electron microscope (SEM). The worn surfaces of the plate specimens were studied by confocal laser scanning microscopy (CLSM). Then, the tribological properties of Mo-Si-B alloy doped with sliding plate specimens of 0.3 wt % La2O3 were investigated against the Si3N4 ball specimens. The friction coefficients of Mo-Si-B alloys decreased and the wear rates of the alloys increased with test load. The high-temperature friction and wear behavior of Mo-Si-B alloy are related to the surface-oxidation and contact-deformation of the alloy at a high temperature. The low friction coefficients and the reduced wear rates are thought to be due to the formation of low friction MoO3 films. MoO3 changed the contact state of the friction pairs and behaved as lubricating films.

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