Alfa fibers for Cereplast bio-composites reinforcement: Effects of chemical and biological treatments on the mechanical properties

The present work is a comparative study of the impact of Alfa fiber modifications on the Cereplast composites mechanical behavior. Various treatments have been employed, including mechanical, soda, saltwater-retting, hot-water treatments and enzymatic treatment using xylanase. Chemical and morphological analyses were carried out in order to determine the changes of the biochemical composition and the dimensions of fibers. Cereplast composites reinforced with Alfa fibers were fabricated using a twin-screw extrusion followed by an injection molding technique with a fiber load of 20 wt. %. Resulting materials were assessed by means of tensile, flexural and Charpy impact testing. Scanning Electron Microscopy analysis was carried out to investigate the interfacial properties of the composites. The results have shown a significant enhancement of mechanical strengths and rigidities for the xylanase-treated fiber composites, owing to the increase of cellulose content, the enhancement of defibrillation level and the improvement of matrix-fiber adhesion. The data proved that the technology of enzymes can be used as a powerful and eco-friendly approach to modify fiber surfaces and to increase their potential of reinforcement.

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Effect of Grain Size and Meso-Texture on the Impact Toughness of Ti-Microalloyed Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.702-703.766 ◽

2011 ◽

Vol 702-703 ◽

pp. 766-769 ◽

Cited By ~ 2

Author(s):

A. Ray ◽

Debalay Chakrabarti

Keyword(s):

Particle Size ◽

Grain Size ◽

Impact Toughness ◽

Microalloyed Steel ◽

Charpy Impact ◽

Impact Testing ◽

Grain Sizes ◽

Matrix Strength ◽

Charpy Impact Testing ◽

The Impact

Charpy impact testing (over the transition temperature rage) on different samples of a Ti-microalloyed steel, having the same average-TiN particle size but different average-ferrite grain sizes, showed that in spite of the presence of large TiN cuboides, ferrite grain refinement can significantly improve the impact toughness, provided the meso-texture (i.e. the intensity of low-angle boundaries) and matrix strength can be restricted to low values.

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Impact Strength of Austenitic and Ferritic-Austenitic Cr-Ni Stainless Cast Steel in -40 and +20°C Temperature

Archives of Metallurgy and Materials ◽

10.2478/amm-2014-0190 ◽

2014 ◽

Vol 59 (3) ◽

pp. 1103-1106

Author(s):

B. Kalandyk ◽

R. Zapała ◽

Ł. Boroń ◽

M. Solecka

Keyword(s):

Impact Strength ◽

Volume Fraction ◽

Cast Steel ◽

Testing Machine ◽

Charpy Impact ◽

Impact Testing ◽

Two Phase ◽

Steel Grades ◽

Charpy Impact Testing ◽

The Impact

Abstract Studies described in this paper relate to common grades of cast corrosion resistant Cr-Ni steel with different matrix. The test materials were subjected to heat treatment, which consisted in the solution annealing at 1060°C followed by cooling in water. The conducted investigations, besides the microstructural characteristics of selected cast steel grades, included the evaluation of hardness, toughness (at a temperature of -40 and +20oC) and type of fracture obtained after breaking the specimens on a Charpy impact testing machine. Based on the results of the measured volume fraction of ferrite, it has been found that the content of this phase in cast austenitic steel is 1.9%, while in the two-phase ferritic-austenitic grades it ranges from 50 to 58%. It has been demonstrated that within the scope of conducted studies, the cast steel of an austenitic structure is characterised by higher impact strength than the two-phase ferritic-austenitic (F-A) grade. The changing appearance of the fractures of the specimens reflected the impact strength values obtained in the tested materials. Fractures of the cast austenitic Cr-Ni steel obtained in these studies were of a ductile character, while fractures of the cast ferritic-austenitic grade were mostly of a mixed character with the predominance of brittle phase and well visible cleavage planes.

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CHARPY IMPACT TESTING ACCREDITATION: LAMEF CASE STUDY

Periódico Tchê Química ◽

10.52571/ptq.v12.n23.2015.28_p_23_pgs_28_33.pdf ◽

2015 ◽

Vol 12 (23) ◽

pp. 28-33

Author(s):

Daniel Antonio Kapper FABRICIO ◽

Vagner Machado COSTA ◽

Etiene Benini MENDES ◽

Afonso REGULY ◽

Telmo Roberto STROHAECKER

Keyword(s):

Impact Test ◽

Standardized Test ◽

Quality Management System ◽

Charpy Impact ◽

Impact Testing ◽

Physical Metallurgy ◽

Type Specimens ◽

Technical Requirements ◽

Charpy Impact Testing ◽

The Impact

The impact test evaluates the energy absorbed by a standardized test specimen in accordance with ASTM E2298 and ASTM E23 standards. This study aims to report the adequacy of the Quality Management System of Physical Metallurgy Laboratory (LAMEF) of UFRGS for the accreditation of the test impact on the Charpy type specimens. An analysis of ISO/IEC 17025 managerial and technical requirements has been performed to identify which points required adjustment. In addition, an external audit was executed, pointing some nonconformities. After performing the necessary actions, the impact test has been successfully accredited, being included in the LAMEF scope.

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Assessment of Pellets from Three Forest Species: From Raw Material to End Use

Forests ◽

10.3390/f12040447 ◽

2021 ◽

Vol 12 (4) ◽

pp. 447

Author(s):

Miguel Alfonso Quiñones-Reveles ◽

Víctor Manuel Ruiz-García ◽

Sarai Ramos-Vargas ◽

Benedicto Vargas-Larreta ◽

Omar Masera-Cerutti ◽

...

Keyword(s):

Chemical Properties ◽

Ash Content ◽

Hot Water ◽

Raw Material ◽

Chemical Components ◽

Energy Yield ◽

Cellulose Content ◽

Fixed Carbon ◽

End Use ◽

The Impact

This study aimed to evaluate and compare the relationship between chemical properties, energy efficiency, and emissions of wood and pellets from madroño Arbutus xalapensis Kunth, tázcate Juniperus deppeana Steud, and encino colorado Quercus sideroxyla Humb. & Bonpl. in two gasifiers (top-lit-up-draft (T-LUD) and electricity generation wood camp stove (EGWCS)) in order to determine the reduction of footprint carbon. In accordance with conventional methodologies, we determined the extracts and chemical components (lignin, cellulose, holocellulose), and the immediate analyses were carried out (volatile materials, fixed carbon, ash content and microanalysis of said ash), as well as the evaluation of emission factors (total suspended particulate matter (PM2.5), CO, CO2, CH4, black carbon (BC), elemental carbon (EC), and organic carbon (OC)). The results were statistically analyzed to compare each variable among species and gasifiers. The raw material analyzed showed how the pH ranged from 5.01 to 5.57, and the ash content ranged between 0.39 and 0.53%. The content values of Cu, Zn, Fe, Mg, and Ca ranged from 0.08 to 0.22, 0.18 to 0.19, 0.38 to 0.84, 1.75 to 1.90, and 3.62 to 3.74 mg kg−1, respectively. The extractive ranges from cyclohexane were 2.48–4.79%, acetone 2.42–4.08%, methanol 3.17–7.99%, and hot water 2.12–4.83%. The range of lignin was 18.08–28.60%. The cellulose content ranged from 43.30 to 53.90%, and holocellulose from 53.50 to 64.02%. The volatile material range was 81.2–87.42%, while fixed carbon was 11.30–17.48%; the higher heating value (HHV) of raw material and pellets presented the ranges 17.68–20.21 and 19.72–21.81 MJ kg−1, respectively. Thermal efficiency showed statistically significant differences (p < 0.05) between pellets and gasifiers, with an average of 31% Tier 3 in ISO (International Organization for Standardization) for the T-LUD and 14% (ISO Tier 1) for EGWCS, with Arbutus xalapensis being the species with the highest energy yield. The use of improved combustion devices, as well as that of selected raw material species, can reduce the impact of global warming by up to 33% on a cooking task compared to the three-stone burner.

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A novel recycled polyethylene terephthalate/polyamide 11 (rPET/PA11) thermoplastic blend

Progress in Rubber Plastics and Recycling Technology ◽

10.1177/14777606211001074 ◽

2021 ◽

pp. 147776062110010

Author(s):

Zahid Iqbal Khan ◽

Zurina Binti Mohamad ◽

Abdul Razak Bin Rahmat ◽

Unsia Habib ◽

Nur Amira Sahirah Binti Abdullah

Keyword(s):

Mechanical Properties ◽

Impact Strength ◽

Flexural Strength ◽

Polyethylene Terephthalate ◽

Practical Implication ◽

Polyamide 11 ◽

Recycled Polyethylene ◽

Twin Screw ◽

Electron Microscopy Analysis ◽

The Impact

This work explores a novel blend of recycled polyethylene terephthalate/polyamide 11 (rPET/PA11). The blend of rPET/PA11 was introduced to enhance the mechanical properties of rPET at various ratios. The work’s main advantage was to utilize rPET in thermoplastic form for various applications. Three different ratios, i.e. 10, 20 and 30 wt.% of PA11 blend samples, were prepared using a twin-screw extruder and injection moulding machine. The mechanical properties were examined in terms of tensile, flexural and impact strength. The tensile strength of rPET was improved more than 50%, while the increase in tensile strain was observed 42.5% with the addition of 20 wt.% of PA11. The improved properties of the blend were also confirmed by the flexural strength of the blends. The flexural strength was increased from 27.9 MPa to 48 MPa with the addition of 30 wt.% PA11. The flexural strain of rPET was found to be 1.1%. However, with the addition of 10, 20 and 30 wt.% of PA11, the flexural strain was noticed as 1.7, 2.1, and 3.9% respectively. The impact strength of rPET/PA11 at 20 wt.% PA11 was upsurged from 110.53 to 147.12 J/m. Scanning electron microscopy analysis revealed a dispersed PA11 domain in a continuous rPET matrix morphology of the blends. This work practical implication would lead to utilization of rPET in automobile, packaging, and various industries.

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