scholarly journals Laser-induced graphitization of polydopamine leads to enhanced mechanical performance while preserving multifunctionality

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Kyueui Lee ◽  
Minok Park ◽  
Katerina G. Malollari ◽  
Jisoo Shin ◽  
Sally M. Winkler ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Diode Laser ◽  
Laser Annealing ◽  
Mechanical Performance ◽  
Conformal Coating ◽  
Inorganic Substrates ◽  
High Roughness ◽  
Functional Versatility ◽  
Blue Diode Laser ◽  
Better Than

Abstract Polydopamine (PDA) is a simple and versatile conformal coating material that has been proposed for a variety of uses; however in practice its performance is often hindered by poor mechanical properties and high roughness. Here, we show that blue-diode laser annealing dramatically improves mechanical performance and reduces roughness of PDA coatings. Laser-annealed PDA (LAPDA) was shown to be >100-fold more scratch resistant than pristine PDA and even better than hard inorganic substrates, which we attribute to partial graphitization and covalent coupling between PDA subunits during annealing. Moreover, laser annealing provides these benefits while preserving other attractive properties of PDA, as demonstrated by the superior biofouling resistance of antifouling polymer-grafted LAPDA compared to PDA modified with the same polymer. Our work suggests that laser annealing may allow the use of PDA in mechanically demanding applications previously considered inaccessible, without sacrificing the functional versatility that is so characteristic of PDA.

EXPERIMENTAL RESULTS ON THE SHEAR BEHAVIOUR OF STEEL FIBRE SELF-COMPACTING CONCRETE (SFSCC) BEAMS

2016 ◽  
Vol 78 (11) ◽  
Author(s):  
Juli Asni Lamide ◽  
Roslli Noor Mohamed ◽  
Ahmad Baharuddin Abd Rahman
Keyword(s):  
Mechanical Properties ◽  
Steel Fibre ◽  
Mechanical Performance ◽  
Load Capacity ◽  
Shear Behaviour ◽  
Self Compacting Concrete ◽  
Steel Fibres ◽  
Concrete Mixtures ◽  
Shear Performance ◽  
Better Than

This paper presents an experimental test program that was carried out to investigate the shear performance of steel fibre self-compacting concrete (SFSCC) beams. In this paper, the mechanical performance of results from all mixtures used to cast normal concrete (NC), self-compacting concrete (SCC) and steel fibre self-compacting concrete (SFSCC) were also investigated. In total, 27 cubes, 9 cylinders, 9 prisms and 9 beams were prepared for the assessment of mechanical properties of three different mixtures. Four beams (125 mm x 250 mm x 2200 mm) were tested and cast using three different concrete mixtures, having two different spacing of stirrups as a result of 50% reduction of the stirrups amount. Three beams with different mixtures having similar stirrups spacing 125mm while the fourth beam with SFSCC mixes having 250mm stirrups spacing. The results show that the mechanical properties were positively affected with steel fibres inclusion. The addition of steel fibres showed an increment up to 40% in the shear load capacity for B-SFSCC125 compared to B-NC125 and B-SCC125.  In addition, the crack pattern of B-SFSCC was found better than B-NC and B-SCC.   

Basalt Fiber Reinforced Concrete

2011 ◽  
Vol 194-196 ◽  
pp. 1103-1108 ◽  
Author(s):  
Yong Xin Yang ◽  
Jie Lian
Keyword(s):  
Mechanical Properties ◽  
Reinforced Concrete ◽  
Water Solubility ◽  
Mechanical Performance ◽  
Basalt Fiber ◽  
Plain Concrete ◽  
Fiber Reinforced Concrete ◽  
Fiber Reinforced ◽  
Mechanical Performances ◽  
Better Than

In this paper, mechanical performances of 480 specimens are tested and influences of basalt fiber ratio, slenderness, soakage material are studied. Results indicate that mechanical properties of BFRC are better than plain concrete. It can be found that the best mechanical performance may be get when the basalt fiber soaked by water-solubility material and its ratio at 8.4 to 14 kg per square meter as well as slenderness at 600 to 800.

scholarly journals THE EFFECT OF NANOCARBON MATERIALS STRUCTURES ON THE PERFOMANCES OF EPOXY-BASED PAINT COATING FOR STEEL SURFACES

2018 ◽  
Vol 55 (5B) ◽  
pp. 287
Author(s):  
Phan Thi Thuy Hang
Keyword(s):  
Mechanical Properties ◽  
Corrosion Protection ◽  
Mechanical Performance ◽  
Epoxy Coatings ◽  
Paint Coating ◽  
Nanocarbon Materials ◽  
Steel Surfaces ◽  
Paint Coatings ◽  
Mechanical Properties And Corrosion ◽  
Better Than

This paper reports the effect of the nanocarbon materials addition on the physico-mechanical properties and corrosion protective ability of epoxy based paint coatings for the steel surfaces. In this work the nanotubes and nanosheets (layers) structures of nanocarbon materials were used for the investigation. The properties of received products were measured by the test techniques for paint coating characterization. The results showed that the addition of the nanocarbon materials (only ratio of 0.1 wt%) significantly improved the physico-mechanical performance and corrosion protection ability of epoxy coatings for steel surfaces. However improvement quantity depends on the structure of nanocarbon materials. The obtained results showed that the nanosheets structure of carbons coatings made the physico-mechanical properties of the epoxy coating increased better than those of nanotube structure. 

scholarly journals 35.1: Blue-Diode Laser Annealing of Amorphous Silicon Films for Low-Cost, Large-Scale Manufacturing of Advanced Displays

2018 ◽  
Vol 49 ◽  
pp. 378-381
Author(s):  
Minok Park ◽  
Seungpyo Hong ◽  
Y.H. Jung ◽  
Suhui Lee ◽  
Yoonsoo Rho ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Diode Laser ◽  
Large Scale ◽  
Laser Annealing ◽  
Low Cost ◽  
Silicon Films ◽  
Blue Diode Laser

scholarly journals Comprehensive analysis of blue diode laser-annealing of amorphous silicon films

2020 ◽  
Vol 696 ◽  
pp. 137779 ◽  
Author(s):  
Minok Park ◽  
Zacharias Vangelatos ◽  
Yoonsoo Rho ◽  
H.K. Park ◽  
Jin Jang ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Diode Laser ◽  
Laser Annealing ◽  
Comprehensive Analysis ◽  
Silicon Films ◽  
Blue Diode Laser

Electron Microscopic Observation of the Longitudinal Organization of Poly (p-Phenylene Terephthalamide) Fibers

1982 ◽  
Vol 40 ◽  
pp. 680-681
Author(s):  
Li Li-Sheng ◽  
L.F. Allard ◽  
W.C. Bigelow
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Microscopic Observation ◽  
Electron Microscopic Observation ◽  
Electron Microscopic ◽  
Aromatic Polyamides ◽  
Radial Arrangement ◽  
Scanning Electron ◽  
Better Than

The aromatic polyamides form a class of fibers having mechanical properties which are much better than those of aliphatic polyamides. Currently, the accepted morphology of these fibers as proposed by M.G. Dobb, et al. is a radial arrangement of pleated sheets, with the plane of the pleats parallel to the axis of the fiber. We have recently obtained evidence which supports a different morphology of this type of fiber, using ultramicrotomy and ion-thinning techniques to prepare specimens for transmission and scanning electron microscopy.

FERRIUM S53

Alloy Digest ◽  
2008 ◽  
Vol 57 (12) ◽  
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Corrosion Resistance ◽  
Heat Treating ◽  
Corrosion Resistant Steel ◽  
Resistant Steel ◽  
Corrosion Resistant ◽  
Aircraft Landing ◽  
Aircraft Landing Gear ◽  
Better Than

Abstract Ferrium S53 was developed for use as a structural corrosion resistant steel for aircraft landing gear. S53 has a corrosion resistance equivalent to 440C, strength equivalent to or better than 300M (AMS 6257A) and SAE 4340 (see Mechanical Properties), optimum microstructure features for maximum fatigue resistance, and a surface hardenability equal to or greater than 67 HRC for wear and fatigue. This datasheet is an update to Alloy Digest SS-942 and SS-1003. This datasheet provides information on composition, physical properties, hardness, and tensile properties as well as fracture toughness. It also includes information on corrosion resistance as well as heat treating and machining. Filing Code: SA-589. Producer or source: QuesTek Innovations, LLC.

Weldability - Behavior of Welded Reinforcement

2019 ◽  
Vol 70 (10) ◽  
pp. 3469-3472
Keyword(s):  
Mechanical Properties ◽  
Chemical Composition ◽  
Mechanical Characteristics ◽  
Mechanical Performance ◽  
Current Work ◽  
Carbon Equivalent ◽  
Work Process ◽  
Ultimate Limit

Weldability involves two aspects: welding behavior of components and safety in operation. The two aspects will be reduced to the mechanical characteristics of the elements and to the chemical composition. In the case of steel reinforcing rebar’s, it is reduces to the percentage of Cech(carbon equivalent) and to the mechanical characteristics: the yielding limit, the ultimate limit, and the elongations which after that represent the ductility class in which the re-bars is framed. The paper will present some types of steel reinforcing rebar’s with its mechanical characteristics and the welding behavior of those elements. In the current work, process-related behavior of welded reinforcement, joint local and global mechanical properties, and their correlation with behavior of normal reinforcement and also the mechanical performance resulted in this type of joints. Keywords: welding behavior, ultimate limit, reinforcing rebar’s

scholarly journals Preparation of Long Sisal Fiber-Reinforced Polylactic Acid Biocomposites with Highly Improved Mechanical Performance

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1124
Author(s):  
Zhifang Liang ◽  
Hongwu Wu ◽  
Ruipu Liu ◽  
Caiquan Wu
Keyword(s):  
Mechanical Properties ◽  
Polylactic Acid ◽  
Mechanical Performance ◽  
Tensile Elongation ◽  
Sisal Fiber ◽  
Fiber Reinforced ◽  
Impact Performance ◽  
The Matrix ◽  
Blending Process ◽  
Extension Direction

Green biodegradable plastics have come into focus as an alternative to restricted plastic products. In this paper, continuous long sisal fiber (SF)/polylactic acid (PLA) premixes were prepared by an extrusion-rolling blending process, and then unidirectional continuous long sisal fiber-reinforced PLA composites (LSFCs) were prepared by compression molding to explore the effect of long fiber on the mechanical properties of sisal fiber-reinforced composites. As a comparison, random short sisal fiber-reinforced PLA composites (SSFCs) were prepared by open milling and molding. The experimental results show that continuous long sisal fiber/PLA premixes could be successfully obtained from this pre-blending process. It was found that the presence of long sisal fibers could greatly improve the tensile strength of LSFC material along the fiber extension direction and slightly increase its tensile elongation. Continuous long fibers in LSFCs could greatly participate in supporting the load applied to the composite material. However, when comparing the mechanical properties of the two composite materials, the poor compatibility between the fiber and the matrix made fiber’s reinforcement effect not well reflected in SSFCs. Similarly, the flexural performance and impact performance of LSFCs had been improved considerably versus SSFCs.

scholarly journals Tribological and Mechanical Properties of Multicomponent CrVTiNbZr(N) Coatings

Coatings ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 41
Author(s):  
Yin-Yu Chang ◽  
Cheng-Hsi Chung
Keyword(s):  
Mechanical Properties ◽  
Nitrogen Content ◽  
Adhesion Strength ◽  
Mechanical Performance ◽  
Bulk Material ◽  
High Entropy Alloy ◽  
Composition Gradient ◽  
Multilayered Structures ◽  
High Entropy ◽  
Alloy Target

Multi-element material coating systems have received much attention for improving the mechanical performance in industry. However, they are still focused on ternary systems and seldom beyond quaternary ones. High entropy alloy (HEA) bulk material and thin films are systems that are each comprised of at least five principal metal elements in equally matched proportions, and some of them are found possessing much higher strength than traditional alloys. In this study, CrVTiNbZr high entropy alloy and nitrogen contained CrVTiNbZr(N) nitride coatings were synthesized using high ionization cathodic-arc deposition. A chromium-vanadium alloy target, a titanium-niobium alloy target and a pure zirconium target were used for the deposition. By controlling the nitrogen content and cathode current, the CrNbTiVZr(N) coating with gradient or multilayered composition control possessed different microstructures and mechanical properties. The effect of the nitrogen content on the chemical composition, microstructure and mechanical properties of the CrVTiNbZr(N) coatings was investigated. Compact columnar microstructure was obtained for the synthesized CrVTiNbZr(N) coatings. The CrVTiNbZrN coating (HEAN-N165), which was deposited with nitrogen flow rate of 165 standard cubic centimeters per minute (sccm), exhibited slightly blurred columnar and multilayered structures containing CrVN, TiNbN and ZrN. The design of multilayered CrVTiNbZrN coatings showed good adhesion strength. Improvement of adhesion strength was obtained with composition-gradient interlayers. The CrVTiNbZrN coating with nitrogen content higher than 50 at.% possessed the highest hardness (25.2 GPa) and the resistance to plastic deformation H3/E*2 (0.2 GPa) value, and therefore the lowest wear rate was obtained because of high abrasion wear resistance.

Sign in / Sign up

Export Citation Format

Share Document