Effect of Heat Treatment on the Photocatalytic Activity of TiO2 Thin Films Fabricated on Ti-6Al-4V Alloy

2014 ◽  
Vol 1035 ◽  
pp. 349-354
Author(s):  
Fang Zhou Jia ◽  
Song Hua Zou ◽  
Guo Jin Sun ◽  
Ji Dan Li ◽  
Zheng Wang
Keyword(s):  
Heat Treatment ◽  
Raman Spectroscopy ◽  
Photocatalytic Activity ◽  
Phase Region ◽  
The Self ◽  
Synergy Effect ◽  
Microcrystalline Structure ◽  
Alloying Element ◽  
Β Phase ◽  
Self Organized

The self-organized oxide nanotube/pore layers were prepared by anodization on ternary Ti-6Al-4V alloys. The morphologies and structures of layers under different heat treatment tempreture were characterized by means of SEM, XRD, XPS and Raman spectroscopy and DRS. The effects of alloying element under different heat treatment tempreture on the structure, composition and opsorption property of the film catalysts were investigated along with their inherent relationships. The results show that two kinds of Ti-Al-V-O nanostructure grown inthe α and β phase region formed on the surface of the alloy. V doped-TiO2can inhibit the formation of anatase. The films show the microcrystalline structure of anatase and rutile and a small amount of V2O5on the surface of film annealed at 400 oC. Moreover, the large surface and the synergy effect of V-doped TiO2and V2O5make sample show the highest photocatalytic activity for the photocatalytic hydrogen evolution.

scholarly journals Effect of strain rate on α-lath thickness of TC17 alloy after deformation and subsequent heat treatment

2020 ◽  
Vol 321 ◽  
pp. 13003
Author(s):  
Zimin Lu ◽  
Jiao Luo ◽  
Miaoquan Li
Keyword(s):  
Heat Treatment ◽  
Strain Rate ◽  
Electron Backscatter Diffraction ◽  
Phase Region ◽  
Subsequent Heat Treatment ◽  
Strain Rates ◽  
Optical Micrograph ◽  
Β Phase ◽  
Electron Backscatter ◽  
Backscatter Diffraction

Effect of strain rate on α-lath thickness of TC17 alloy with a basketweave microstructure was studied in the present work. For this purpose, this alloy was deformed in the β phase region and subsequently soluted and aged in α+β phase region. Moreover, optical micrograph (OM) and electron backscatter diffraction (EBSD) were applied to analyze the change of lath thickness at different strain rates. The result showed that α-lath thickness increased with increasing strain rate. This phenomenon was possibly attributed to the higher degree of variant selection (DVS) at higher strain rate (0.1 s-1). The higher DVS was beneficial for the formation of parallel α-lath colonies during cooling after deformation. And, these parallel α-lath colonies would more easily grow up and coarsen during subsequent heat treatment. Therefore, α-lath at higher strain rate is more thick.

scholarly journals Effect of Mo, V and Zr on the microstructure and mechanical properties of Ti2AlNb alloys

2020 ◽  
Vol 321 ◽  
pp. 08003
Author(s):  
Yujun Du ◽  
Xianghong Liu ◽  
Jinshan Li ◽  
Wenzhong Luo ◽  
Yongsheng He ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Melting Process ◽  
Phase Region ◽  
Arc Furnace ◽  
Micro Hardness ◽  
Β Phase ◽  
Before And After ◽  
B2 Phase ◽  
O Phase

Small button ingots of Ti2AlNb alloys with different contents of Mo, V and Zr were melted by vacuum non-consumable arc furnace. Due to the rapid cooling rate during melting process, only β grains without precipitation were observed in most of the button ingots and no regular phenomenon was found. However, when the samples were heated to β phase region and then furnace cooled to room temperate, different morphologies and quantities of primary α phase and second O phase formed from the β grains of different samples. It is suggested that the morphology of α phase was changed from lamellar to quadrilateral with increasing V and the lath O increased with increasing Zr. Besides, the residual β/B2 phase increased with increasing Mo and V. The EDS results showed that Al and Zr were enriched in α phase whereas Nb, Mo and V were enriched in β/B2 phase. The micro-hardness of these samples before and after heat treatment was detected and the micro-hardness increased with increasing Zr and decreasing Mo and V.

Synthesis and Magnetic Properties of Nanocomposite Magnets Self-Organized from FeB-Nd-Nb Metallic Glasses

2008 ◽  
Vol 1118 ◽  
Author(s):  
R Tamura ◽  
S Kobayashi ◽  
T Fukuzaki ◽  
M Kamiko
Keyword(s):  
Heat Treatment ◽  
Metallic Glasses ◽  
Treatment Condition ◽  
Heat Treatment Condition ◽  
The Self ◽  
Quenching Rate ◽  
Glass Forming ◽  
Self Organized ◽  
Nanocomposite Magnets ◽  
Treatment Conditions

ABSTRCTChange of the magnetic property of Fe-B-Nd-Nb alloys was investigated with replacing Nb by a glass forming element Zr under constant quenching rate as well as heat treatment conditions. As a result, the coercivity significantly increases up to 1207 kA/m when the half of Nd is replaced by Zr, which is presumably due to grain refinement of the Nd2Fe14B phase. The self-organized nanograin magnets are attractive for future applications since their coercivity can be further improved by reducing the grain size via optimizing the Zr concentration, the quenching rate and the subsequent heat treatment condition.

Hydrogen-Induced Microstructure Optimization of the Ti-6Al-4V Alloy

2020 ◽  
Vol 986 ◽  
pp. 24-32
Author(s):  
Mohammed Kasim Mohsun
Keyword(s):  
Heat Treatment ◽  
Electron Backscatter Diffraction ◽  
Solution Treatment ◽  
Aging Treatment ◽  
Martensite Phase ◽  
Hydrogen Gas ◽  
Hydrogen Treatment ◽  
Alloying Element ◽  
X Ray ◽  
Β Phase

To obtain advanced materials through the development of traditional materials without the addition of another alloying element, advanced heat treatment can be used. One such innovative process is a thermo-hydrogen treatment (THT); it facilitates a purposeful adjustment of an improved microstructure using hydrogen as a temporary alloying element within heat treatment. In this paper, the five-step process of homogenization, hydrogenation, solution treatment, dehydrogenation, and aging was used in THT. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), backscattered electron (BSE), electron backscatter diffraction (EBSD), and X-ray diffraction (XRD) were utilized to analyze the phases and phase transformations in Ti-6Al-4V. Three different homogeneous microstructures were established for the investigation using different homogenization parameters values. The hydrogenation was carried out for these microstructures via hydrogen gas charging leading to hydrogen concentrations for the formation of hydride (δ TiH2). After the solution treatment at a temperature above β transus temperature (Tβ), the metastable phases of a martensitic structure consisting of a mixture of α ́ (hcp) and α ́ ́ (orthorhombic) was found. Steps 4 and 5 of THT were a vacuum annealing (hydrogen degassing) followed by aging treatment. The aging treatment was applied to complete the martensite phase decomposition and the precipitation of two phases. By means of this THT cycle, very fine equiaxed microstructures could be established. These microstructures consist of the αs phase (secondary α) in the β phase matrix and the α2 phase (Ti3Al) in the αp phase. The precipitation of these phases increases the strength of the Ti-6Al-4V alloy and, consequently, enhances the mechanical properties. No evidence of the δ phase was found.

Growth mechanism and photocatalytic activity of self-organized N-doped (BiO)2CO3 hierarchical nanosheet microspheres from bismuth citrate and urea

2014 ◽  
Vol 43 (18) ◽  
pp. 6631-6642 ◽  
Author(s):  
Fan Dong ◽  
Ting Xiong ◽  
Rui Wang ◽  
Yanjuan Sun ◽  
Yanke Jiang
Keyword(s):  
Photocatalytic Activity ◽  
Growth Mechanism ◽  
The Self ◽  
Bismuth Citrate ◽  
Self Organized

A new growth mechanism was proposed for the self-organized N-doped (BiO)2CO3 hierarchical nanosheet microspheres with efficient and durable photocatalytic activity.

Investigation of the Properties of Heat Treated Rolled Aluminum Zinc Alloy (7072-T6)

2013 ◽  
Vol 1 (2) ◽  
pp. 79-91
Author(s):  
Kamal Abdulkareem Mohammed
Keyword(s):  
Heat Treatment ◽  
Mechanical Tests ◽  
Phase Region ◽  
Zinc Alloy ◽  
Artificial Ageing ◽  
Zinc Alloys ◽  
Β Phase ◽  
Alloy Type ◽  
Structural Applications ◽  
Rolled Aluminum

The effects of heat treatment on the properties of rolled aluminum zinc alloy type 7072-T6 are study in this work. Representative samples of aluminum zinc alloys were subjected to heat treatment processes which are; Solution heat treatment follow by Artificial Ageing in the different order. The aluminum zinc alloys were heated to the initial temperature of 600 ºC and water quenched. The quenched aluminum zinc alloys were subjected to(lamellae formation) by reheating it to the dual-phase region at a temperature of 150ºC and then rapidly quenched in water. The (lamellae formation) samples was take an Artificial Ageing at 400 ºC to provide an alloy containing strong, tough and lath α –β phase in a soft and ductile α - matrix. Mechanical tests were carried out on the samples and the results shows that the aluminum zinc alloys developed has excellent combination of tensile strength, hardness and impact strength which is very good for structural applications.

Problem behavior in autism spectrum disorders: A paradigmatic self-organized perspective of network structures

2019 ◽  
Vol 42 ◽  
Author(s):  
Lucio Tonello ◽  
Luca Giacobbi ◽  
Alberto Pettenon ◽  
Alessandro Scuotto ◽  
Massimo Cocchi ◽  
...  
Keyword(s):  
Autism Spectrum Disorder ◽  
Problem Behaviors ◽  
Autism Spectrum ◽  
The Self ◽  
Network Structures ◽  
Self Organized ◽  
Critical Equilibrium ◽  
Self Organized Criticality ◽  
Acute Agitation ◽  
Spectrum Disorders

AbstractAutism spectrum disorder (ASD) subjects can present temporary behaviors of acute agitation and aggressiveness, named problem behaviors. They have been shown to be consistent with the self-organized criticality (SOC), a model wherein occasionally occurring “catastrophic events” are necessary in order to maintain a self-organized “critical equilibrium.” The SOC can represent the psychopathology network structures and additionally suggests that they can be considered as self-organized systems.

Effects of Heat Treatment Temperature on Photocatalytic Activity of TiO2/SiO2 Composite Aerogels

2013 ◽  
Vol 27 (10) ◽  
pp. 1079-1083
Author(s):  
Zhao-Hui LIU ◽  
Gen-Liang HOU ◽  
Xun-Jia SU ◽  
Feng GUO ◽  
Zhou XIAO ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Photocatalytic Activity ◽  
Heat Treatment Temperature ◽  
Treatment Temperature ◽  
Composite Aerogels

scholarly journals Tripeptide Self-Assembly into Bioactive Hydrogels: Effects of Terminus Modification on Biocatalysis

Molecules ◽  
2020 ◽  
Vol 26 (1) ◽  
pp. 173
Author(s):  
Marina Kurbasic ◽  
Ana M. Garcia ◽  
Simone Viada ◽  
Silvia Marchesan
Keyword(s):  
Self Assembly ◽  
The Self ◽  
Chemical Modifications ◽  
Ability To Work ◽  
Active Compounds ◽  
Future Design ◽  
Self Organized ◽  
The Future ◽  
Bio Material ◽  
Supramolecular Catalysts

Bioactive hydrogels based on the self-assembly of tripeptides have attracted great interest in recent years. In particular, the search is active for sequences that are able to mimic enzymes when they are self-organized in a nanostructured hydrogel, so as to provide a smart catalytic (bio)material whose activity can be switched on/off with assembly/disassembly. Within the diverse enzymes that have been targeted for mimicry, hydrolases find wide application in biomaterials, ranging from their use to convert prodrugs into active compounds to their ability to work in reverse and catalyze a plethora of reactions. We recently reported the minimalistic l-His–d-Phe–d-Phe for its ability to self-organize into thermoreversible and biocatalytic hydrogels for esterase mimicry. In this work, we analyze the effects of terminus modifications that mimic the inclusion of the tripeptide in a longer sequence. Therefore, three analogues, i.e., N-acetylated, C-amidated, or both, were synthesized, purified, characterized by several techniques, and probed for self-assembly, hydrogelation, and esterase-like biocatalysis. This work provides useful insights into how chemical modifications at the termini affect self-assembly into biocatalytic hydrogels, and these data may become useful for the future design of supramolecular catalysts for enhanced performance.

scholarly journals Investigation of single-domain Au silicide nanowires on Si(110) formed for Au coverages in the monolayer regime

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Stephan Appelfeller
Keyword(s):  
Fermi Level ◽  
Surface Structure ◽  
Density Of States ◽  
The Self ◽  
Single Domain ◽  
Photoemission Spectroscopy ◽  
Annealing Temperatures ◽  
Self Organized ◽  
Scanning Tunnelling ◽  
Tunnelling Microscopy

AbstractThe self-organized formation of single domain Au silicide nanowires is observed on Si(110). These nanowires are analysed using scanning tunnelling microscopy (STM) and spectroscopy (STS) as well as photoemission spectroscopy (PES). Core-level PES is utilised to confirm the formation of Au silicide and establish its presence as the top most surface structure, i.e., the nanowires. The growth of the Au silicide nanowires and their dimensions are studied by STM. They form for Au coverages of about 1 monolayer and are characterized by widths of about 2 to 3 nm and heights below 1 nm while reaching lengths exceeding 500 nm when choosing appropriate annealing temperatures. Valence band PES and STS indicate a small but finite density of states at the Fermi level typical for compound metals.

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