scholarly journals The analysis of effect of heat treatment temperature on micro structure, crystal structure and hardness material on alloy Zr 96,2 Sn 2,3Nb1.1 Fe0,4

Author(s):  
Bungaran Saing ◽  
Budiarto
2015 ◽  
Vol 1784 ◽  
Author(s):  
Mingu Kim ◽  
Gwanghyo Choi ◽  
Daeheung Yoo ◽  
Kwangmin Lee

ABSTRACTThe band gap energy of the TiO2 photocatalytic is high at 3.2 eV. Ultraviolet (UV) light irradiation (<388nm) is required for the photocatalytic application. The lowering the band gap energy of TiO2 and enlarging light absorbing area are effective ways to enhance the efficiency of photocatalytic activity. Furthermore, the morphology and crystal structure of nanosized TiO2 considerably influences its photocatalytic behavior.In this study, sodium titanate nanorods were formed using an alkali-treatment and were heat treated at different temperatures. The photoelectrochemical properties of sodium titanate nanorods was measured as a function of heat treatment temperature. The nanorods were prepared on the surface of Ti disk with a diameter of 15mm and a thickness of 3mm. Ti disk was immersed in 5 M NaOH aqueous solution at a temperature of 60 °C for 24 h. Morphology of sodium titanate nanorods was observed using FE-SEM. Crystal structure of sodium titanate nanorods was analyzed using X-ray diffractometer. Photoluminescence (PL) and electrochemical impedance spectroscopy (EIS) was used to evaluate photoelectrochemical properties of sodium titanate nanorods. The thin amorphous sodium titanate layer was formed during alkali-treatment. The sodium titanate layer was changed to nanorods after heat treatment at a temperature of 700 °C. The thickness and length of sodium titanate nanorods obtained at 700 °C were around 100 nm and 1μm, respectively. The crystal structure of sodium titanate was identified with Na2Ti6O13. Above 900 °C, the morphology of nanorods changed to agglomerated shape and the thickness of nanorods increased to 1 μm. The lowest value of PL was obtained at a temperature of 700 °C, while nonalkali treated specimen showed the highest value of PL. EIS revealed that polarization resistance at interface between sodium titanate nanorods and electrolyte was increased with increasing heat treatment temperature.


2020 ◽  
Vol 13 (3) ◽  
pp. 196-201 ◽  
Author(s):  
Fang Wei ◽  
Liu Ling ◽  
Xu Lan

Background: Nanocomposites loaded with metal oxides, such as CuO and ZnO, have excellent optical, electrical, mechanical and chemical properties, which result in their great potential applications in optoelectronic devices, sensors, photocatalysts and other fields. Especially, electrospun metal- oxide-loaded nanofibers have attracted much attention in many fields. However, the single-needle Electrospinning (ES) inhibits the industrial application of these electrospun nanofiber composites. Bubble-Electrospinning (BE) is an effective free surface ES for mass production of nanofiber membranes loaded with metal oxide. Few relevant patents to the topic have been reviewed and introduced. Methods: The BE was used to prepare mass production of Cu(Ac)2 /Zn(Ac)2/ PVDF/ PAN Composite Nanofiber Membranes (CNFMs). Then PVDF/PAN CNFMs containing CuO and ZnO nanocrystals were obtained by heat-treatment. Finally, CuO nanosheets and ZnO nanorods were successfully grown on the surface of PVDF/PAN CNFMs using hydrothermal method. In addition, the morphology and crystal structure of CNFMs were investigated by scanning electron microscopy (SEM) and X-Ray Powder Diffractometer (XRD). Results: The morphology and crystal structure of the samples were characterized by SEM and XRD. The results showed the heat treatment temperature of 150oC and the hydrothermal temperature of 150oC were the optimal process parameters for the fabrication of PVDF/PAN CNFMs loaded with CuO and ZnO nanocrystals, and a higher heat treatment temperature results in higher crystallinity of ZnO and CuO. Conclusion: CuO/ZnO/PVDF/PAN CNFMs were successfully prepared by a combination of BE, heattreatment and hydrothermal method. The ZnO/CuO beads obtained by heat treatment is the key point of growing ZnO/CuO nanocrystals, and the growth temperature has great effect on the morphology of ZnO/CuO nanocrystals.


2013 ◽  
Vol 27 (10) ◽  
pp. 1079-1083
Author(s):  
Zhao-Hui LIU ◽  
Gen-Liang HOU ◽  
Xun-Jia SU ◽  
Feng GUO ◽  
Zhou XIAO ◽  
...  

2009 ◽  
Vol 18 (12) ◽  
pp. 935-938
Author(s):  
H. Kobori ◽  
T. Asahi ◽  
Y. Yamasaki ◽  
A. Sugimura ◽  
T. Taniguchi ◽  
...  

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1264
Author(s):  
Teng-Chun Yang ◽  
Tung-Lin Wu ◽  
Chin-Hao Yeh

The influence of heat treatment on the physico-mechanical properties, water resistance, and creep behavior of moso bamboo (Phyllostachys pubescens) was determined in this study. The results revealed that the density, moisture content, and flexural properties showed negative relationships with the heat treatment temperature, while an improvement in the dimensional stability (anti-swelling efficiency and anti-water absorption efficiency) of heat-treated samples was observed during water absorption tests. Additionally, the creep master curves of the untreated and heat-treated samples were successfully constructed using the stepped isostress method (SSM) at a series of elevated stresses. Furthermore, the SSM-predicted creep compliance curves fit well with the 90-day full-scale experimental data. When the heat treatment temperature increased to 180 °C, the degradation ratio of the creep resistance (rd) significantly increased over all periods. However, the rd of the tested bamboo decreased as the heat treatment temperature increased up to 220 °C.


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