scholarly journals Heat Treatment of Basalt Fiber Reinforced Expanded Clay Concrete with Increased Strength for Cast-In-Situ Construction

Fibers ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 67
Author(s):  
Makhmud Kharun ◽  
Sergey Klyuev ◽  
Dmitry Koroteev ◽  
Paschal C. Chiadighikaobi ◽  
Roman Fediuk ◽  
...  

Expanded clay concrete (ECC) is a promising structural material for buildings due to its light weight and heat- and sound-insulating properties. Adding basalt fibers (BFs) in ECC reduces its brittleness and enhances its mechanical properties. The heat treatment (HT) of BF-reinforced ECC can significantly accelerate the strength growth during cast-in-situ construction, which allows the reduction of the turnover of the formwork and the construction period, as well as leading to lower construction costs. This paper presents an HT technology for load-bearing structures, containing a BF-reinforced ECC mix and using infrared rays for cast-in-situ construction. The issue of the strength growth of BF-reinforced ECC during HT has been studied. Microsilica and fly ash were added to the ECC mix to obtain a compressive strength of more than 20 MPa. Four different mixes of ECC with chopped BFs in the ratios of 1:0, 1:0.0045, 1:0.009 and 1:0.012 by weight of cement were studied. Test specimens were heated by infrared rays for 7, 9, 11, 13, 16 and 24 h. Then, the heat-treated specimens were tested for compressive strength after 0.5, 4, 12 and 24 h cooling periods. The analysis and evaluation of the experimental data were carried out based on probability theory and mathematical statistics. Mathematical models are proposed for forecasting the strength growth of BF-reinforced ECC during cast-in-situ construction.

2019 ◽  
Vol 972 ◽  
pp. 84-90
Author(s):  
Makhmud Kharun ◽  
Dmitry D. Koroteev

Self-compacting high-strength concrete (SCHSC) is an innovative concrete that has superior physical and mechanical properties, and does not require vibration for placing and compaction. Heat treatment (HT) of SCHSC can significantly accelerate the strength growth during cast-in-situ construction, and allows to reduce the turnover of formwork, the labor costs for construction, and the construction period. The issue of strength development of SCHSC during HT has been studied. SCHSC of R28 = 100 MPa was studied. Test specimens were cured with HT by infrared rays for 7, 9, 11, 13, 16 and 24 hours. Then warmed specimens were tested for compressive strength after 0.5, 4, 12 and 24 hours of cooling period. Study was carried out on the basis of analyzing, generalizing and evaluations of experimental data. A mathematical model is proposed for determining the compressive strength of SCHSC after one day of curing with HT.


2020 ◽  
Vol 100 (1) ◽  
pp. 165-174 ◽  
Author(s):  
Piotr Micek ◽  
Katarzyna Słota ◽  
Paweł Górka

The aim of this study was to determine the effect of heat treatment alone or in combination with the addition of lignosulfonate (LSO3) on canola cake protein, lysine, and methionine degradation in the rumen. Cold-pressed canola cake was left untreated, heated at 90, 110, 130, or 150 °C, or processed with 5% of LSO3 (in dry matter) and then heated. Effective rumen degradability of crude protein (CP), lysine, and methionine was less for treated than untreated canola cake (P < 0.05) and decreased with increased temperature of heating, but particularly when canola cake was heated at 150 °C (quadratic, P < 0.01). In general, effective rumen degradability of CP, lysine, and methionine was less for canola cake heated at 130 °C in combination with LSO3 compared with canola cake heat treated only (quadratic × LSO3 interaction, P ≤ 0.07). Results of this study indicate that high temperature heating (130 °C or greater for 60 min) may be necessary to protect canola cake protein from degradation in the rumen, and the combination of heat treatment and LSO3 may be more effective in protecting canola cake protein, lysine, and methionine from degradation in the rumen than the use of heat treatment only.


2000 ◽  
Vol 80 (1) ◽  
pp. 215-219 ◽  
Author(s):  
Marina A. G. von Keyserlingk ◽  
E. Weurding ◽  
Mary Lou Swift ◽  
C. F. Wright ◽  
J. A. Shelford ◽  
...  

The effect of adding 5% calcium lignosulfonate (LSO3) and heat to canola screenings on in situ ruminal and intestinal dry matter (DM) and crude protein (CP) disappearance in Holstein cows was investigated. Treatments consisted of untreated canola screenings, canola screenings that had been heated to 100 °C for 30 or 60 min and canola screenings that had 5% (wt wt−1) LSO3 added and were subsequently heated at 100 °C for 0, 30 or 60 min. Results indicate that treatment of canola screenings with 5% LSO3 and heated to 100 °C for 60 min was effective in reducing rumen degradation of DM and CP with a corresponding increase in disappearance in the lower gastrointestinal tract when compared to untreated and heat-treated canola screenings. Key words: Canola screenings, rumen by-pass protein, heat treatment, lignosulfonate


2002 ◽  
Vol 17 (6) ◽  
pp. 1371-1375 ◽  
Author(s):  
Jaeyoung Yang ◽  
Cheonman Shim ◽  
Donggeun Jung

We investigated effects of postdeposition heat treatment (HT) on the properties of plasma polymer films deposited by plasma-enhanced chemical vapor deposition using a mixture of decahydronaphthalene and tetraethyl orthosilicate as the precursors, which were referred to as plasma-polymerized decahydronaphthalene:tetraethyl orthosilicate (PPDHN:TEOS) films. HTs at 350, 450, and 500 °C decreased the relative dielectric constant k of the PPDHN:TEOS films from 3.16, the k value of the as-deposited film, to 2.82, 2.72, and 3.02, respectively. The change of k value as a function of HT temperature was correlated with the change of Fourier transform infrared absorption peaks of O–H, C = O, and Si-related groups. As the HT temperature increased, the thermal stability of the PPDHN:TEOS film increased. PPDHN:TEOS films, as-deposited or heat treated, showed leakage current density in the order of 10−7 A/cm2 at 1 MV/cm.


1990 ◽  
Vol 181 ◽  
Author(s):  
Bharat Bhushan ◽  
S.P. Murarka

ABSTRACTUsing an in-situ stress measurement technique that measures stress as a function of annealing temperature, instabilities in mechanical stress induced by heat treatment in a variety of doped/undoped SiO2 films deposited by APCVD, LPCVD and PECVD techniques have been investigated. A large hysteresis in mechanical stress, caused by first heat treatment to which the as-deposited films are subjected, has been observed in films deposited by APCVD/LPCVD techniques. No such hysteresis is obsesrved in films deposited by PECVD technique. Hysteresis in APCVD/LPCVD films is found to vanish once the films are heat treated at or above 800°C. The results are discussed in terms of oxide densification, the presence of hydrogenous species, and phosphorous.


2017 ◽  
Vol 24 (Supp02) ◽  
pp. 1850028
Author(s):  
BINFENG LU ◽  
YUNXIA CHEN ◽  
MENGJIA XU

(Cr, Fe)7C3/[Formula: see text]-Fe composite layer has been in situ synthesized on a low carbon steel surface by vacuum electron beam VEB irradiation. The synthesized samples were then subdued to different heat treatments to improve their impaired impact toughness. The microstructure, impact toughness and wear resistance of the heat-treated samples were studied by means of optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM), microhardness tester, impact test machine and tribological tester. After heat treatment, the primary and eutectic carbides remained in their original shape and size, and a large number of secondary carbides precipitated in the iron matrix. Since the Widmanstatten ferrite in the heat affected zone (HAZ) transformed to fine ferrite completely, the impact toughness of the heat-treated samples increased significantly. The microhardness of the heat-treated samples decreased slightly due to the decreased chromium content in the iron matrix. The wear resistance of 1000[Formula: see text]C and 900[Formula: see text]C heat-treated samples was almost same with the as-synthesized sample. While the wear resistance of the 800[Formula: see text]C heat-treated one decreased slightly because part of the austenite matrix had transformed to ferrite matrix, which reduced the bonding of carbides particulates.


1982 ◽  
Vol 104 (3) ◽  
pp. 234-240 ◽  
Author(s):  
T. J. Louzon

A heat treatment has been developed which produces significant improvements in the tensile properties of Cu-15Ni-8Sn spinodal alloy. The treatment involves solution heat treatment in the two-phase region rather than the single-phase region normally used. After quenching and aging, increased strength and ductility of the alloy over single phase solution heat-treated and aged values were found. The mechanical properties obtained were superior to any previously observed for material of the compositions studied in the solution treated, quenched, and aged condition. Also, the alloys’ transformation kinetics were greatly slowed by the two phase heat-treatment. It is suggested that the increase in strength and slow kinetics of transformation observed are caused by grain size effects and by grain boundary modifications. Resistivity data and etching response corroborate these arguments.


2019 ◽  
Vol 25 (3) ◽  
pp. 281-285
Author(s):  
Dhanashekar MANICKAM ◽  
Senthil Kumar VELUKKUDI SANTHANAM

Aluminium alloys are subjected to heat treatment to increase the strength and corrosion properties. This paper aims to study the effect of heat treatment on the compression behaviour of A356 alloy under quasi static condition and barreling effect. The various heat treatments are: (i) solution heat treatment of 1 h at 540 °C + natural aging 0 h + artificial aging at 180 °C up to 5.5 h, (ii) solution heat treatment of 3 h at 540 °C + natural aging for 20 h + artificial aging at 180 °C up to 5.5 h, and (iii) solution heat treatment of 6 h at 540 °C + natural aging for 20 h + artificial aging at 180 °C up to 5.5 h. Specially to understand the influence of artificial aging at every 0.5 h up to 5.5 h, the specimens were heat treated. From the results, solutionizing for 1 hr have a better compression strength irrespective of the artificial aging. Natural aging had decreased the ductility but increased the strength property. Artificial aging had a significant effect on the compressive strength and peak strength were obtained at 4 h irrespective of solutionizing heat treatment. Compressive strength increased by 33 % for 1 h of solutionizing and 4 h of artificial aged specimen when compared to non-heat treated alloy. Two mathematical relations discussed in literature were used for calculating the radius of the barreled surface followed by validation. DOI: http://dx.doi.org/10.5755/j01.ms.25.3.20442


2002 ◽  
Vol 736 ◽  
Author(s):  
Yifan Xu ◽  
Paul Berger ◽  
Jai Cho ◽  
Richard B. Timmons

ABSTRACTPolyallylamine films, deposited on Si wafers by radio frequency (RF) pulsed plasma polymerization (PPP), were employed as insulating layers of metal-insulator-semiconductor (MIS) capacitors. The insulating polymer films were deposited at substrate temperatures of 25°C and 100°C. Multiple frequency capacitance-voltage (C-V) measurements indicated that an in-situ heat treatment during film deposition increased the insulator dielectric constant. The dielectric constant, calculated from the C-V data, rose from 3.03 for samples with no heat treatment to 3.55 for samples with an in-situ heat treatment. For both sample sets, the I-V data demonstrate a low leakage current value (<20fA) up to 100V with an area of 0.0307 mm2, resulting in a current density of <0.65 pA/mm2. Hysteresis in the C-V curves with differing sweep directions was more pronounced for in-situ heat-treated samples indicative of positive mobile ions.


1993 ◽  
Vol 309 ◽  
Author(s):  
J. Nucci ◽  
H. Neves ◽  
Y. Shacham ◽  
E. Eisenbraun ◽  
B. Zheng ◽  
...  

AbstractCopper thin films were deposited by sputtering, electron beam evaporation, and electroless plating onto nitride membranes for TEM analysis. The samples were heat treated in-situ from room temperature to 600 °C for structural and chemical analysis. The as-deposited and heat treated microstructures were investigated. Orientation changes with heat treatment and reactions among the sample layers were analyzed by electron diffraction. This work provides baseline information for a study of the thermal evolution of copper lines.


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