Fabrication, Tensile Properties, and Photodecomposition of Basalt Fiber-Reinforced Cellulose Acetate Matrix Composites

Cellulose acetate (CA) is widely used as an alternative to conventional plastics because of the minor environmental impact of its decomposition cycle. This study synthesized five-layer environmentally friendly composites from CA bioplastic and basalt fibers (BFs) to produce a high-strength marine-biodegradable polymer. Maleic anhydride-grafted polypropylene (PP-g-MAH) was mixed with CA as a surface-active agent (SAA) to understand the effect of surface treatment on the mechanical properties of the composite. Tensile tests and scanning electron microscopy were conducted to observe the fracture surfaces. The ultimate tensile strength (UTS) of the BF/CA composite increased by approximately a factor of 4 after adding 11 vol.% unidirectional BF. When the SAA was added, the UTS of the composite with 11 vol.% BF was multiplied by a factor of about 7, which indicates that the surface treatment has a significant positive effect on the mechanical properties. However, the improvement is not apparent when the added BFs are in a plain weave with a vertical orientation. A photodecomposition experiment was then conducted by adding TiO2. Observing the UTS changes of the CA and BF/CA composites, the effect of the photocatalyst on the decomposition of the materials was explored.

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Investigations on the Mechanical Properties and Formability of Friction Stir Welded Tailored Blanks

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.344.143 ◽

2007 ◽

Vol 344 ◽

pp. 143-150 ◽

Cited By ~ 6

Author(s):

Gianluca Buffa ◽

Livan Fratini ◽

Marion Merklein ◽

Detlev Staud

Keyword(s):

Mechanical Properties ◽

Stress Condition ◽

Research Effort ◽

High Strength Steels ◽

High Strength ◽

Tensile Tests ◽

Friction Stir ◽

Tailored Blanks ◽

Sheet Stamping ◽

Wide Range

Tight competition characterizing automotive industries in the last decades has determined a strong research effort aimed to improve utilized processes and materials in sheet stamping. As far as the latter are regarded light weight alloys, high strength steels and tailored blanks have been increasingly utilized with the aim to reduce parts weight and fuel consumptions. In the paper the mechanical properties and formability of tailored welded blanks made of a precipitation hardenable aluminum alloy but with different sheet thicknesses, have been investigated: both laser welding and friction stir welding have been developed to obtain the tailored blanks. For both welding operations a wide range of the thickness ratios has been considered. The formability of the obtained blanks has been characterized through tensile tests and cup deep drawing tests, in order to show the formability in dependency of the stress condition; what is more mechanical and metallurgical investigations have been made on the welded joints.

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Experimental Investigation into Corrosion Effect on Mechanical Properties of High Strength Steel Bars under Dynamic Loadings

International Journal of Corrosion ◽

10.1155/2018/7169681 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Hui Chen ◽

Jinjin Zhang ◽

Jin Yang ◽

Feilong Ye

Keyword(s):

Mechanical Properties ◽

Strain Rate ◽

Dynamic Loading ◽

High Strength Steel ◽

High Strength ◽

Tensile Tests ◽

Reinforcing Steel ◽

Test Results ◽

Cross Sectional ◽

Steel Bars

The tensile behaviors of corroded steel bars are important in the capacity evaluation of corroded reinforced concrete structures. The present paper studies the mechanical behavior of the corroded high strength reinforcing steel bars under static and dynamic loading. High strength reinforcing steel bars were corroded by using accelerated corrosion methods and the tensile tests were carried out under different strain rates. The results showed that the mechanical properties of corroded high strength steel bars were strain rate dependent, and the strain rate effect decreased with the increase of corrosion degree. The decreased nominal yield and ultimate strengths were mainly caused by the reduction of cross-sectional areas, and the decreased ultimate deformation and the shortened yield plateau resulted from the intensified stress concentration at the nonuniform reduction. Based on the test results, reduction factors were proposed to relate the tensile behaviors with the corrosion degree and strain rate for corroded bars. A modified Johnson-Cook strength model of corroded high strength steel bars under dynamic loading was proposed by taking into account the influence of corrosion degree. Comparison between the model and test results showed that proposed model properly describes the dynamic response of the corroded high strength rebars.

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Changing in Fatigue Life of 300 M Bainitic Steel After Laser Carburizing and Plasma Nitriding

MATEC Web of Conferences ◽

10.1051/matecconf/201816521002 ◽

2018 ◽

Vol 165 ◽

pp. 21002 ◽

Cited By ~ 2

Author(s):

Antonio J. Abdalla ◽

Douglas Santos ◽

Getúlio Vasconcelos ◽

Vladimir H. Baggio-Scheid ◽

Deivid F. Silva

Keyword(s):

Mechanical Properties ◽

Fatigue Life ◽

Plasma Nitriding ◽

Fatigue Behavior ◽

High Strength ◽

Tensile Tests ◽

Steel Sample ◽

Fatigue Tests ◽

300M Steel ◽

Structural Applications

In this work 300M steel samples is used. This high-strength steel is used in aeronautic and aerospace industry and other structural applications. Initially the 300 M steel sample was submitted to a heat treatment to obtain a bainític structure. It was heated at 850 °C for 30 minutes and after that, cooled at 300 °C for 60 minutes. Afterwards two types of surface treatments have been employed: (a) using low-power laser CO2 (125 W) for introducing carbon into the surface and (b) plasma nitriding at a temperature of 500° C for 3 hours. After surface treatment, the metallographic preparation was carried out and the observations with optical and electronic microscopy have been made. The analysis of the coating showed an increase in the hardness of layer formed on the surface, mainly, among the nitriding layers. The mechanical properties were analyzed using tensile and fatigue tests. The results showed that the mechanical properties in tensile tests were strongly affected by the bainitic microstructure. The steel that received the nitriding surface by plasma treatment showed better fatigue behavior. The results are very promising because the layer formed on steel surface, in addition to improving the fatigue life, still improves protection against corrosion and wear.

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Tensile properties of the FFF-processed thermoplastic polyurethane (TPU) elastomer

10.21203/rs.3.rs-299979/v1 ◽

2021 ◽

Author(s):

Budi Arifvianto ◽

Teguh Nur Iman ◽

Benidiktus Tulung Prayoga ◽

Rini Dharmastiti ◽

Urip Agus Salim ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Low Cost ◽

Thermoplastic Polyurethane ◽

High Strength ◽

Tensile Tests ◽

Uniaxial Tensile ◽

Fused Filament Fabrication ◽

Raster Angle ◽

Manufacturing Techniques

Abstract Fused filament fabrication (FFF) has become one of the most popular, practical, and low-cost additive manufacturing techniques for fabricating geometrically-complex thermoplastic polyurethane (TPU) elastomer. However, there are still some uncertainties concerning the relationship between several operating parameters applied in this technique and the mechanical properties of the processed material. In this research, the influences of extruder temperature and raster orientation on the mechanical properties of the FFF-processed TPU elastomer were studied. A series of uniaxial tensile tests was carried out to determine tensile strength, strain, and elastic modulus of TPU elastomer that had been printed with various extruder temperatures, i.e., 190–230 °C, and raster angles, i.e., 0–90°. Thermal and chemical characterizations were also conducted to support the analysis in this research. The results obviously showed the ductile and elastic characteristics of the FFF-processed TPU, with specific tensile strength and strain that could reach up to 39 MPa and 600%, respectively. The failure mechanisms operating on the FFF-processed TPU and the result of stress analysis by using the developed Mohr’s circle are also discussed in this paper. In conclusion, the extrusion temperature of 200 °C and raster angle of 0° could be preferred to be applied in the FFF process to achieve high strength and ductile TPU elastomer.

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Effect of Quenching and Partitioning Processing on Microstructure and Mechanical Properties of a Low Alloyed Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.941.52 ◽

2018 ◽

Vol 941 ◽

pp. 52-57

Author(s):

Bernd Pfleger ◽

Marina Gruber ◽

Gerald Ressel ◽

Peter Gruber ◽

Matthew Galler ◽

...

Keyword(s):

Mechanical Properties ◽

High Strength ◽

Phase Evolution ◽

Tensile Tests ◽

Austenite Phase ◽

Phase Fraction ◽

Quenching Temperature ◽

Quenching And Partitioning ◽

Low Alloyed Steel ◽

A Minor

The concept of quenching and partitioning (Q&P) is a tool to generate steels with high strength and high ductility resulting from a relatively high amount of martensite and austenite. As the parameters of the Q&P treatment influence the strength and ductility properties, the goal of this work was to analyze the effects of varying quenching and partitioning temperatures on the phase evolution, on the retained austenite phase fraction and on the mechanical properties. The phase evolution during heat treatment was analyzed by dilatometer and the microstructure after processing was characterized by light microscopy in combination with color etching according to Klemm. The austenite phase fraction and its carbon content were determined by X-Ray diffraction and the mechanical properties were evaluated by tensile tests. It is shown that the quenching temperature has a minor impact on the phase fraction of austenite as well as its stabilization by carbon and thus, also the mechanical properties. Furthermore, austenite transformation during the partitioning treatment is illustrated.

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Effect of Intercritical Annealing and Austempering on the Microstructure and Mechanical Properties of a High Silicon Manganese Steel

Metals ◽

10.3390/met10111448 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1448 ◽

Cited By ~ 1

Author(s):

Mattia Franceschi ◽

Luca Pezzato ◽

Claudio Gennari ◽

Alberto Fabrizi ◽

Marina Polyakova ◽

...

Keyword(s):

Mechanical Properties ◽

Intercritical Annealing ◽

High Strength ◽

Xrd Analysis ◽

Tensile Tests ◽

Manganese Steel ◽

Microstructure And Mechanical Properties ◽

Martensitic Microstructure ◽

Steel Grades ◽

High Silicon

High Silicon Austempered steels (AHSS) are materials of great interest due to their excellent combination of high strength, ductility, toughness, and limited costs. These steel grades are characterized by a microstructure consisting of ferrite and bainite, accompanied by a high quantity retained austenite (RA). The aim of this study is to analyze the effect of an innovative heat treatment, consisting of intercritical annealing at 780 °C and austempering at 400 °C for 30 min, on the microstructure and mechanical properties of a novel high silicon steel (0.43C-3.26Si-2.72Mn wt.%). The microstructure was characterized by optical and electron microscopy and XRD analysis. Hardness and tensile tests were performed. A multiphase ferritic-martensitic microstructure was obtained. A hardness of 426 HV and a tensile strength of 1650 MPa were measured, with an elongation of 4.5%. The results were compared with those ones obtained with annealing and Q&T treatments.

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Effect of Ce Addition on Modifying the Microstructure and Achieving a High Elongation with a Relatively High Strength of As-Extruded AZ80 Magnesium Alloy

Materials ◽

10.3390/ma12010076 ◽

2018 ◽

Vol 12 (1) ◽

pp. 76 ◽

Cited By ~ 6

Author(s):

Zheng Wang ◽

Jin-Guo Wang ◽

Ze-Yu Chen ◽

Min Zha ◽

Cheng Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Dynamic Recrystallization ◽

Grain Refinement ◽

High Strength ◽

Tensile Tests ◽

Area Fraction ◽

Schmid Factor ◽

High Elongation ◽

Az80 Alloy ◽

Ce Content

Forming magnesium alloys with rare earth elements (La, Gd, Nd, Y, Ce) is a routine method for modifying their microstructure and properties. In the present work, the effect of Ce addition on the microstructure evolution and the mechanical properties of as-extruded Mg-8Al-0.5Zn (AZ80) alloy was investigated. All of the extruded AZ80-xCe (x = 0, 0.2, 0.8 and 1.4 wt %) alloys exhibited equiaxed grains formed by fully dynamic recrystallization, and the grain size of the extruded AZ80 alloy was remarkably reduced by ~56.7% with the addition of 1.4 wt % Ce. Furthermore, the bulk-shaped Al4Ce phase formed when Ce was first added, with the Ce content rising to 0.8 wt % or higher, and Al4Ce particles in both the nano- and micron sizees were well distributed in the primary α-Mg matrix. The area fraction of the Al4Ce particles expanded with increasing Ce content, providing more nuclei for dynamic recrystallization, which could contribute to the grain refinement. The results of the tensile tests in this study showed that Ce addition effectively improved the room temperature formability of the as-extruded AZ80 alloy, without sacrificing strength. The significantly improved mechanical properties were ascribed to excellent grain refinement, weakened texture strength, an increased Schmid factor, and a reduced area fraction of low-angle grain boundaries, all resulting from Ce addition to the as-extruded AZ80 alloy. The contribution of the nano-Al4Ce precipitates on improving the mechanical properties was also discussed in this paper.

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Investigation on mechanical properties and failure mechanisms of basalt fiber reinforced aluminum matrix composites under different loading conditions

Journal of Composite Materials ◽

10.1177/0021998317733807 ◽

2017 ◽

Vol 52 (14) ◽

pp. 1907-1914 ◽

Cited By ~ 5

Author(s):

Yang Zhiming ◽

Liu Jinxu ◽

Feng Xinya ◽

Li Shukui ◽

Xu Yuxin ◽

...

Keyword(s):

Mechanical Properties ◽

Failure Mechanisms ◽

Basalt Fiber ◽

Aluminum Matrix ◽

Fiber Content ◽

Aluminum Matrix Composites ◽

Matrix Composites ◽

Fiber Reinforced ◽

Basalt Fibers ◽

Static Compression

Basalt fiber reinforced aluminum matrix composites with different fiber contents (i.e. 0 wt%, 10 wt%, 30 wt% and 50 wt%) were prepared by hot-press sintering. Microstructure analysis indicates that basalt fibers are uniformly distributed in 10% basalt fiber reinforced aluminum matrix composite. The interfacial bonding between basalt fibers and aluminum matrix is good, and there is no interface reaction between basalt fiber and aluminum matrix. Quasi-static tensile, quasi-static compression and dynamic compression properties of basalt fiber reinforced aluminum composites were studied, and the influences of basalt fiber content on mechanical properties were discussed. Meanwhile, the failure mechanisms of basalt fiber reinforced aluminum matrix composites with different fiber content were analyzed.

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Mechanical Properties of Densified Untwisted Carbon Nanotube Yarn / Epoxy Composites

Volume 1: Processing ◽

10.1115/msec2015-9342 ◽

2015 ◽

Author(s):

Risa Yoshizaki ◽

Kim Tae Sung ◽

Atsushi Hosoi ◽

Hiroyuki Kawada

Keyword(s):

Mechanical Properties ◽

Volume Fraction ◽

Polymer Matrix Composites ◽

High Strength ◽

Matrix Composites ◽

Specific Strength ◽

The Matrix ◽

Cnt Arrays ◽

Strength And Stiffness ◽

Long Fibers

Carbon nanotubes (CNTs) have very high specific strength and stiffness. The excellent properties make it possible to enhance the mechanical properties of polymer matrix composites. However, it is difficult to use CNTs as the reinforcement of long fibers because of the limitation of CNT growth. In recent years, a method to spin yarns from CNT forests has developed. We have succeeded in manufacturing the unidirectional composites reinforced with the densified untwisted CNT yarns. The untwisted CNT yarns have been manufactured by drawing CNTs through a die from vertically aligned CNT arrays. In this study, the densified untwisted CNT yarns with a polymer treatment were fabricated. The tensile strength and the elastic modulus of the yarns were improved significantly by the treatment, and they were 1.9 GPa and 140 GPa, respectively. Moreover, the polymer treatment prevented the CNT yarns from swelling due to impregnation of the matrix resin. Finally, the high strength CNT yarn composites which have higher volume fraction than a conventional method were successfully fabricated.

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Evaluation of Mechanical Properties and Comprehensive Modeling of CMC with Stiff and Weak Matrices

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.45.1435 ◽

2006 ◽

Vol 45 ◽

pp. 1435-1443 ◽

Cited By ~ 8

Author(s):

Dietmar Koch ◽

Kamen Tushtev ◽

Jürgen Horvath ◽

Ralf Knoche ◽

Georg Grathwohl

Keyword(s):

Mechanical Properties ◽

Mechanical Response ◽

Ceramic Matrix Composites ◽

High Strength ◽

Shear Mode ◽

Matrix Composites ◽

Matrix Interface ◽

Strain Behavior ◽

Fiber Matrix Interface ◽

Fiber Matrix

The mechanical properties of ceramic matrix composites (CMC) depend on the individual properties of fibers and matrix, the fiber-matrix interface, the microstructure and the orientation of the fibers. The fiber-matrix interface of ceramics with stiff matrices (e.g. CVI-derived SiC/SiC) must be weak enough to allow crack deflection and debonding in order to achieve excellent strength and strain to failure (weak interface composites WIC). This micromechanical behavior has been intensively investigated during the last 20 years. With the development of CMC with weak matrices (weak matrix composites WMC) as e.g. oxide/oxide composites or polymer derived CMC the mechanical response can not be explained anymore by these models as other microstructural mechanisms occur. If the fibers are oriented in loading direction in a tensile test the WMC behave almost linear elastic up to failure and show a high strength. Under shear mode or if the fibers are oriented off axis a significant quasiplastic stress-strain behavior occurs with high strain to failure and low strength. This complex mechanical behavior of WMC will be explained using a finite element (FE) approach. The micromechanical as well as the FE models will be validated and attributed to the different manufacturing routes.

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