scholarly journals Ozone Treatment as a Process of Quality Improvement Method of Rhubarb (Rheum rhaponticum L.) Petioles during Storage

2020 ◽  
Vol 10 (22) ◽  
pp. 8282
Author(s):  
Miłosz Zardzewiały ◽  
Natalia Matlok ◽  
Tomasz Piechowiak ◽  
Józef Gorzelany ◽  
Maciej Balawejder
Keyword(s):  
Mechanical Properties ◽  
Room Temperature ◽  
Mechanical Tests ◽  
Raw Material ◽  
Ozone Treatment ◽  
Chemical Parameters ◽  
Oxidative Potential ◽  
Rheum Rhaponticum ◽  
Improvement Method ◽  
Quality Improvement Method

The aim of the study was to identify the effects of ozone treatment reflected by the microbial, mechanical properties and selected chemical parameters during the storage of rhubarb petioles. For this purpose, after they were harvested, rhubarb petioles were treated with gaseous ozone at concentrations of 10 and 100 ppm, for the duration of 5, 15 and 30 min. Subsequently, the plant material was stored at room temperature for 14 days. After this time, the raw material was subjected to a number of chemical and mechanical tests. It was shown that the rhubarb petioles treated with ozone at a rate of 100 ppm for 30 min were characterized by the lowest loss of water content. It was also found that, compared to the control, most samples subjected to ozone treatment presented better mechanical properties, as well as higher oxidative potential and contents of polyphenols and vitamin C. Based on these findings, it was determined that ozone treatment largely increases storage stability of rhubarb.

Fabrication and investigation on the properties of ilmenite (FeTiO3)-based Al composite by accumulative roll bonding

2019 ◽  
Vol 54 (10) ◽  
pp. 1259-1271 ◽  
Author(s):  
Medhat Elwan ◽  
A Fathy ◽  
A Wagih ◽  
A R S Essa ◽  
A Abu-Oqail ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Accumulative Roll Bonding ◽  
Room Temperature ◽  
Volume Fraction ◽  
Raw Material ◽  
Accumulative Roll Bonding Process ◽  
Roll Bonding ◽  
Hardness Tests ◽  
Al Composite

In the present study, the aluminum (Al) 1050–FeTiO3 composite was fabricated through accumulative roll bonding process, and the resultant mechanical properties were evaluated at different deformation cycles at ambient temperature. The effect of the addition of FeTiO3 particle on the microstructural evolution and mechanical properties of the composite during accumulative roll bonding was investigated. The Al–2, 4, and 8 vol.% FeTiO3 composites were produced by accumulative roll bonding at room temperature. The results showed improvement in the dispersions of the particles with the increase in the number of the rolling cycles. In order to study the mechanical properties, tensile and hardness tests were applied. It was observed that hardness and tensile strength improve with increasing accumulative roll bonding cycles. The microhardness and tensile strength of the final composites are significantly improved as compared to those of original raw material Al 1050 and increase with increasing volume fraction of FeTiO3, reaching a maximum of ∼75 HV and ∼169 MPa for Al–8 vol.% FeTiO3 at seventh cycle, respectively.

Investigation of the Mechanical Properties of Thin Films by Bulge Test

2009 ◽  
Vol 156-158 ◽  
pp. 477-482
Author(s):  
Audrey Hémel ◽  
Alain Jacques ◽  
Thomas Schenk ◽  
Tomáš Kruml
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Room Temperature ◽  
Mechanical Tests ◽  
Bulge Test ◽  
Gold Films ◽  
Test Device

A new bulge test device has been built, with the aim to perform mechanical tests on membranes with a thickness in the 100 nm to 10 µm range, between room temperature and 900°C. The first tests on Si3N4 and gold films give results consistent with literature data.

Effect of Melt Quality and Quenching Temperature on the Mechanical Properties of SIMA 2024 and 7075

2012 ◽  
Vol 445 ◽  
pp. 171-176
Author(s):  
Engin Tan ◽  
Ali Riza Tarakcilar ◽  
Derya Dispinar
Keyword(s):  
Mechanical Properties ◽  
Room Temperature ◽  
Mechanical Tests ◽  
Fatigue Tests ◽  
Grain Structure ◽  
Quenching Temperature ◽  
Reduced Pressure ◽  
Pressure Test ◽  
Sima Process ◽  
Spherical Grains

Spherical grains can be obtained by several semisolid processes in aluminium alloys. One of these methods is called Strain Induced Melt Activated (SIMA). In this work, commercially available 2024 and 7075 alloys were subjected SIMA process. First, optimised process parameters were investigated for the homogeneous spherical grain structure. This was followed by solution heat treatment of the parts. For the quenching medium, room temperature and 80°C boiling water was selected. The effect of different quenching temperatures over the mechanical properties was tested. Hardness, tensile and fatigue tests were applied. In addition, reduced pressure test was used to assess alloy quality and the results were compared with the mechanical tests.

scholarly journals Deformation Mechanism, Microstructure, and Mechanical Properties Evolution of Mg–Gd–Y–Zr Alloy during Cold Torsion

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2067
Author(s):  
Hongchao Xiao ◽  
Zhengjiang Yang ◽  
Jie Li ◽  
Yingchun Wan
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Basal Slip ◽  
Room Temperature ◽  
Deformation Mode ◽  
Equivalent Strain ◽  
Mechanical Tests ◽  
Fiber Texture ◽  
Basal Pole ◽  
Zr Alloy

Mg–Gd–Y–Zr alloy was subjected to torsion of various strain levels at room temperature. Obvious traces of basal slip were observed in the twisted alloy. Dislocations of <c+a> were also observed, but there were no signs of significant sliding. Even in the sample whose equivalent strain became 0.294, 101¯0 twinning and 101¯2 twinning were rarely seen. The deformation mode with predominant basal <a> dislocations and subordinate <c+a> dislocations resulted in a modified Y fiber texture with a basal pole slightly dispersed at about 70° from the twist axis. Mechanical tests revealed that the tensile strength and compressive strengths increased simultaneously after twisting.

scholarly journals Thermal and Mechanical Assessment of PLA-SEBS and PLA-SEBS-CNT Biopolymer Blends for 3D Printing

2021 ◽  
Vol 11 (13) ◽  
pp. 6218
Author(s):  
Balázs Ádám ◽  
Zoltán Weltsch
Keyword(s):  
Mechanical Properties ◽  
3D Printing ◽  
Mechanical Tests ◽  
The Other ◽  
Raw Material ◽  
Bending Test ◽  
Thermal And Mechanical Properties ◽  
Scanning Calorimetry ◽  
Partial Fracture ◽  
The Impact

Polylactic acid (PLA) is one of the most promising biopolymers often used as a raw material in 3D printing in many industrial areas. It has good mechanical properties, is characterized by high strength and stiffness, but unfortunately, it has some disadvantages; one is brittleness, and the other is slow crystallization. Amounts of 1–5% SEBS (styrene-ethylene-butylene-styrene) thermoplastic elastomer were blended into the PLA and the thermal and mechanical properties were investigated. DSC (Differential Scanning Calorimetry) measurements on the filaments have shown that SEBS increases the initial temperature of crystallization, thereby acting as a nucleating agent. The cooling rate of 3D printing, on the other hand, is too fast for PLA, so printed specimens behave almost amorphously. The presence of SEBS increases the impact strength, neck formation appears during the tensile test, and in the bending test, the mixture either suffers partial fracture or only bends without fracture. Samples containing 1% SEBS were selected for further analysis, mixed with 0.06 and 0.1% carbon nanotubes (CNTs), and tested for thermal and mechanical properties. As a result of CNTs, another peak appeared on the DSC curve in addition to the original single-peak crystallization, and the specimens previously completely broken in the mechanical tests suffered partial fractures, and the partially fractured pieces almost completely regained their original shape at the end of the test.

scholarly journals Epoxidation of Kraft Lignin as a Tool for Improving the Mechanical Properties of Epoxy Adhesive

Molecules ◽  
2020 ◽  
Vol 25 (11) ◽  
pp. 2513
Author(s):  
Julia R. Gouveia ◽  
Guilherme E. S. Garcia ◽  
Leonardo Dalseno Antonino ◽  
Lara B. Tavares ◽  
Demetrio J. dos Santos
Keyword(s):  
Mechanical Properties ◽  
Kraft Lignin ◽  
Mechanical Tests ◽  
Epoxy Adhesive ◽  
Raw Material ◽  
Partial Replacement ◽  
Industrial Grade ◽  
Curing Kinetic ◽  
Wide Availability ◽  
Open Question

Owing to its chemical structure, wide availability and renewable nature, lignin is a promising candidate for the partial replacement of fossil-based raw material in the synthesis of epoxy resins. Its poor compatibility has been reported to be one of the main drawbacks in this domain. On the other hand, a well-established modification method for lignin epoxidation has been used for many years for the improvement of lignin compatibility. However, the extent of the effect of lignin epoxidation on the improvement of bio-based epoxy mechanical properties, applied as adhesives, is still an open question in the literature. In this context, a pristine and industrial grade kraft lignin (AKL) was reacted with epichlorohydrin to yield epoxidized lignin (E-AKL) in this work. Afterwards, AKL or E-AKL were separately blended with petroleum-based epoxy resin at 15 and 30 wt% and cured with a commercial amine. The adhesive curing kinetic was evaluated using a novel technique for thermal transition characterization, Temperature Modulated Optical Refractometry (TMOR); the results showed that the incorporation of AKL reduces the crosslinking rate, and that this effect is overcome by lignin modification. Mechanical tests revealed an improvement of impact and practical adhesion strength for samples containing 15 wt% of E-AKL. These results elucidate the effect of lignin epoxidation on the application of lignin-based epoxy adhesives, and might support the further development and application of these bio-based materials.

The Effect of Chemical Composition of Sintering Atmosphere on the Structure and Mechanical Properties of PM Manganese Steels with Chromium and Molybdenum Additions

2007 ◽  
Vol 534-536 ◽  
pp. 753-756 ◽  
Author(s):  
Maciej Sulowski ◽  
Andrzej Cias ◽  
Marin Stoytchev ◽  
Tchavdar Andreev
Keyword(s):  
Mechanical Properties ◽  
Chemical Composition ◽  
Impact Toughness ◽  
Room Temperature ◽  
Surface Hardness ◽  
Mechanical Tests ◽  
Dew Point ◽  
Green Density ◽  
Sintering Atmosphere ◽  
Manganese Steels

The effect of chemical composition of the sintering atmosphere on the density, microstructure and mechanical properties of Fe-3%Mn-(Cr)-(Mo)-0.3%C is described. Pre-alloyed Astaloy CrM and CrL, ferromanganese and graphite powders were the starting powders. Following the pressing in rigid dies, compacts (green density approx. 6.8-7.1 g/cm3) were sintered at 1120 and 1250°C in atmospheres with different H2 and N2 content. The dew point of the sintering atmospheres was below -60°C. Subsequently samples were furnace cooled to room temperature. Tensile and transverse rupture strengths, elongation, R0.2 yield offset, impact toughness and apparent surface hardness were examined. Following the mechanical tests, to investigate microstructure optical microscopy was employed. As the results show, sintering in nitrogen-rich atmospheres allow to achieve comparable properties of the specimens with those of the specimens sintered in hydrogen-rich atmosphere. It means that it is possible to produce sintered Fe-Mn-Cr-Mo-C PM steels in safe and cheaper nitrogen-rich atmosphere.

Fabrication and Mechanical Properties of Ni3Al-Al2O3 Composites

1988 ◽  
Vol 133 ◽  
Author(s):  
C. G. McKamey ◽  
G. L. Povirk ◽  
J. A. Horton ◽  
T. N. Tiegs ◽  
E. K. Ohriner
Keyword(s):  
Mechanical Properties ◽  
Room Temperature ◽  
Matrix Material ◽  
Hot Extrusion ◽  
Tensile Tests ◽  
Mechanical Tests ◽  
Interfacial Structure ◽  
High Temperature Strength ◽  
Four Point Bending ◽  
The Matrix

ABSTRACTThe objective of this study is to develop a metal-matrix composite based on the intermetallic alloy Ni3Al reinforced with Al2O3 fibers, with improved high-temperature strength and lower density compared to the matrix material. This paper summarizes results of initial fabrication and mechanical tests on specimens produced using IC-15 [Ni-24% Al-0.24% B (at.%)] and IC-218 [Ni-16.5% Al-8% Cr-0.4% Zr-0.1% B (at.%)], with 20 vol. % Al2O3 fibers. Fabrication methods include both hot-pressing and hot-extrusion. Mechanical tests include four-point bending and tensile tests. The integrity of the fiber-matrix interface was studied and correlated with mechanical properties. Tensile ductilities of approximately 10% at room temperature were achieved for Ni3Al/Al2O3 composites with controlled material processing and interfacial structure. Fabrication of composites by hot-extrusion produced better tensile properties at room temperature, but superplastic behavior (i.e., low strengths, high ductilities) at 1000°C.

Mechanical Properties and Dislocation Structure of Single Crystal Cdte Deformed in Compression at 300°C

1976 ◽  
Vol 34 ◽  
pp. 592-593
Author(s):  
Ernest L. Hall ◽  
J. B. Vander Sande
Keyword(s):  
Mechanical Properties ◽  
Single Crystal ◽  
Dislocation Structure ◽  
Room Temperature ◽  
Elevated Temperatures ◽  
Strain Curve ◽  
Optical Devices ◽  
Semiconductor Compound ◽  
Wide Range ◽  
Sample Orientation

The present paper describes research on the mechanical properties and related dislocation structure of CdTe, a II-VI semiconductor compound with a wide range of uses in electrical and optical devices. At room temperature CdTe exhibits little plasticity and at the same time relatively low strength and hardness. The mechanical behavior of CdTe was examined at elevated temperatures with the goal of understanding plastic flow in this material and eventually improving the room temperature properties. Several samples of single crystal CdTe of identical size and crystallographic orientation were deformed in compression at 300°C to various levels of total strain. A resolved shear stress vs. compressive glide strain curve (Figure la) was derived from the results of the tests and the knowledge of the sample orientation.

Autonomous self-healing polyisoprene elastomers with high modulus and good toughness based on the synergy of dynamic ionic crosslinks and highly disordered crystals

2020 ◽  
Vol 11 (41) ◽  
pp. 6549-6558
Author(s):  
Yohei Miwa ◽  
Mayu Yamada ◽  
Yu Shinke ◽  
Shoichi Kutsumizu
Keyword(s):  
Mechanical Properties ◽  
Room Temperature ◽  
Self Healing ◽  
High Modulus ◽  
Disordered Crystals ◽  
Ionic Crosslinks

We designed a novel polyisoprene elastomer with high mechanical properties and autonomous self-healing capability at room temperature facilitated by the coexistence of dynamic ionic crosslinks and crystalline components that slowly reassembled.

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