Enhancement of Mechanical Properties and Porosity of Concrete Using Steel Slag Coarse Aggregate

This paper investigates the possibility of utilizing steel slags produced in the steelmaking industry as an alternative to burnt clay brick aggregate (BA) in concrete. Within this context, physical, mechanical (i.e., compressive and splitting tensile strength), length change, and durability (porosity) tests were conducted on concrete made with nine different percentage replacements (0%, 10%, 20%, 30%, 40%, 50%, 60%, 80%, and 100% by volume of BA) of BA by induction of furnace steel slag aggregate (SSA). In addition, the chemical composition of aggregate through X-ray fluorescence (XRF) analysis and microstructural analysis through scanning electron microscopy (SEM) of aggregates and concrete were performed. The experimental results show that the physical and mechanical properties of concrete made with SSA were significantly higher than that of concrete made with BA. The compressive and tensile strength increased by 73% when SSA fully replaced BA. The expansion of concrete made with SSA was a bit higher than the concrete made with BA. Furthermore, a significant lower porosity was observed for concrete made with SSA than BA, which decreased by 40% for 100% SSA concrete than 100% BA concrete. The relation between compressive and tensile strength with the porosity of concrete mixes are in agreement with the relationships presented in the literature. This study demonstrates that SSA can be used as a full replacement of BA, which is economical, conserves the natural aggregate, and is sustainable building material since burning brick produces a lot of CO2.

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Influence of active inorganic fillers on the physical and mechanical properties of polyvinyl chloride wood-plastic composites when immersed

BioResources ◽

10.15376/biores.16.1.789-804 ◽

2020 ◽

Vol 16 (1) ◽

pp. 789-804

Author(s):

Qiang Jin ◽

Lin Zhu ◽

Jiedeerbieke Madiniyeti ◽

Chunxia He ◽

Li Li

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Water Absorption ◽

Polyvinyl Chloride ◽

Steel Slag ◽

Physical And Mechanical Properties ◽

Control Group ◽

Wood Plastic Composites ◽

Plastic Composites ◽

Inorganic Fillers

Hydration-active steel slag and slag micropowder were used as inorganic fillers with silane coupling agent (KH550) to prepare wheat straw/polyvinyl chloride wood-plastic composites (WPCs) by extrusion molding. A 35-day immersion and a pre-immersion test were carried out to analyze the influence of steel slag and slag micropowder on the physical and mechanical properties of the WPCs under wet conditions. Results showed the following: (1) KH-550 exhibited a good surface modification effect on the activated steel slag and slag micropowder, (2) an increase in the activated steel slag and slag micropowder content could effectively reduce the percent water absorption of the WPCs by 20% to 25% and the expansion by 20% to 24%, respectively, compared with the control group, but had a limited effect on the tensile strength retention, and (3) pre-immersion could effectively induce the synergistic reinforcement effect of the active fillers, resulting in reaching the saturated water absorption within 20 days. The water absorption and tensile strength were respectively 18% to 25% lower and 1.5% to 3% higher than those of the composites without pre-immersion. The results of this study could provide experimental data and theoretical references for the influence of hydration-active inorganic fillers on WPC properties.

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Nanostructured Films Produced from the Bleached Pinus sp. Kraft Pulp

Floresta e Ambiente ◽

10.1590/2179-8087.019115 ◽

2019 ◽

Vol 26 (4) ◽

Author(s):

Lívia Cássia Viana ◽

Graciela Ines Bolzon de Muñiz ◽

Washington Luiz Esteves Magalhães ◽

Alan Sulato de Andrade ◽

Silvana Nisgoski ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Kraft Pulp ◽

Physical And Mechanical Properties ◽

Compact Structure ◽

Nanostructured Films ◽

Bleached Kraft Pulp ◽

Lower Porosity ◽

Density Values ◽

Number Of Passes

ABSTRACT This study investigates the physical and mechanical properties of nanostructured films produced from Pinus sp. kraft pulp. To obtain the nanocellulose, the bleached kraft pulp was submitted to six different grinding regimes: two, five, ten, 20, 30, and 40 passes through the grinder. The influence of the number of passes was evaluated through the films’ physical and mechanical properties. The results show that the nanofibers reduced the thickness and considerably increased the density values of the fabricated films. The tensile strength increased more than 300% and the burst index was ten times higher in relation to normal papers. The more compact structure and lower porosity caused by the larger contact surface between nanofibers in the nanostructured films resulted in higher values of density, tensile strength, and burst resistance.

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Improving the surface quality and mechanical properties of selective laser sintered PA2200 components by the vibratory surface finishing process

SN Applied Sciences ◽

10.1007/s42452-021-04371-4 ◽

2021 ◽

Vol 3 (3) ◽

Author(s):

Hamaid M. Khan ◽

Tolga B. Sirin ◽

Gurkan Tarakci ◽

Mustafa E. Bulduk ◽

Mert Coskun ◽

...

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Tensile Strength ◽

Additive Manufacturing ◽

Microstructural Analysis ◽

Surface Hardness ◽

Physical And Mechanical Properties ◽

Surface Finishing ◽

Finishing Process ◽

Wide Range

Abstract This paper attempts to improve the physical and mechanical properties of selective laser sintered polyamide PA2200 components through a vibratory surface finishing process by inducing severe plastic deformation at the outer surface layers. The industrial target of additive manufacturing components is to obtain structures having surface roughness, hardness, and other mechanical properties equivalent to or better than those produced conventionally. Compared to the as-built SLS PA2200 samples, vibratory surface finishing treated specimens exhibited a smooth surface microstructure and more favorable roughness, hardness, and tensile strength. Also, the duration of the vibratory surface finishing process showed a further improvement in the surface roughness and hardness of the SLS samples. Compared to the as-built state, the roughness and hardness of the surface-treated samples improved by almost 90% and 15%, respectively. Consequently, microstructural analysis indicates that lower surface roughness and enhanced surface hardness is a crucial factor in influencing the overall tensile strength of SLS-PA2200 components. We consider that the combination of VSF and SLS processes can successfully handle a wide range of potential applications. This study also highlights the efficiency and applicability of the vibratory surface finishing process to other additive manufacturing processes and materials. Graphic abstract

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Characterization of physical and mechanical properties of aluminium based composites reinforced with titanium diboride particulates

Journal of Composite Materials ◽

10.1177/0021998320980800 ◽

2020 ◽

pp. 002199832098080

Author(s):

Dipankar Dey ◽

Abhijit Bhowmik ◽

Ajay Biswas

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Titanium Diboride ◽

Microstructural Analysis ◽

Physical And Mechanical Properties ◽

High Strength ◽

Casting Process ◽

Matrix Alloy ◽

Stir Casting ◽

Sem Analysis

Particulate reinforced aluminium matrix composites are one of the most attractive approaches for applications where high strength and hardness combinations are necessary. The aspiration of this study is to investigate the effect of titanium diboride addition on physical and mechanical properties of Al2024-TiB2 composites manufactured using stir casting route, by varying the weight percentages (wt.%) (0, 3, 6 and 9 percent) of titanium diboride particulates. During the casting process, stirring time and speed were kept constant and same for all the composites. Microstructural analysis demonstrates uniformity in TiB2 distribution and also strong matrix-reinforcement bonding which can be as a result of magnesium addition and preheating of titanium diboride particles before incorporating into the molten aluminium. With an increment in the wt.% of TiB2 particulates, hardness and tensile strength of the prepared composites improved, a significant improvement in hardness as well as tensile strength is encountered in Al2024-9% TiB2 composite, which is 44.94% and 35.49% higher than Al2024 matrix alloy, respectively. SEM analysis of the fractured surfaces revealed that the mode of fracture of unreinforced material is purely ductile but reinforced material fractured by nucleation of cracks and plastic deformation.

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A STUDY ON MECHANICAL PROPERTIES AND STRUCTURE OF ANHYDRITE BINDER MODIFIED BY ULTRA-DISPERSED SILTSTONE

Engineering Structures and Technologies ◽

10.3846/est.2019.11950 ◽

2020 ◽

Vol 11 (3) ◽

pp. 78-86

Author(s):

Yury Tokarev ◽

Grigory Yakovlev ◽

Zarina Saidova ◽

Valery Grakhov ◽

Alexander Buryanov ◽

...

Keyword(s):

Mechanical Properties ◽

Microstructural Analysis ◽

Physical And Mechanical Properties ◽

Uniform Structure ◽

Calcium Sulfate Dihydrate ◽

Mineral Additive ◽

Lower Porosity ◽

Combined Action ◽

First Time ◽

Crystalline Hydrates

This research is devoted to modification of physical and mechanical properties and structure of a binder based on natural anhydrite. A sedimentary rock siltstone was added into the composition as a mineral ultrafine additive. The presence of aluminosilicate minerals proves that finely ground siltstone can be used as a mineral additive in the composition of the anhydrite binder, accelerating crystallization of gypsum new formations and densifying the structure of gypsum stone. For the first time, the effectiveness of using sodium and ammonium phosphates as hardening activators of an anhydrite binder was shown. Siltstone, added to the composition in the amount from 0 to 5%, lead to up to 40% increase in strength, which is due to the action of siltstone particles as “crystallization centers” and formation of crystalline hydrates of calcium sulfate dihydrate on their surface. Combined action of calcined siltstone and lime leads to a 45% increase in strength due to the additional compaction by new hydration products formed in the course of metakaolin and lime interaction. Microstructural analysis showed that samples with calcined siltstone and lime have a more dense and uniform structure with a lower porosity, compared to those with only natural siltstone.

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Damage Evolution of Granodiorite after Heating and Cooling Treatments

Minerals ◽

10.3390/min11070779 ◽

2021 ◽

Vol 11 (7) ◽

pp. 779

Author(s):

Mohamed Gomah ◽

Guichen Li ◽

Salah Bader ◽

Mohamed Elkarmoty ◽

Mohamed Ismael

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Failure Mode ◽

Physical And Mechanical Properties ◽

P Wave ◽

Physical Parameters ◽

Slow Cooling ◽

Heating And Cooling ◽

Natural Rock ◽

The Impact

The awareness of the impact of high temperatures on rock properties is essential to the design of deep geotechnical applications. The purpose of this research is to assess the influence of heating and cooling treatments on the physical and mechanical properties of Egyptian granodiorite as a degrading factor. The samples were heated to various temperatures (200, 400, 600, and 800 °C) and then cooled at different rates, either slowly cooled in the oven and air or quickly cooled in water. The porosity, water absorption, P-wave velocity, tensile strength, failure mode, and associated microstructural alterations due to thermal effect have been studied. The study revealed that the granodiorite has a slight drop in tensile strength, up to 400 °C, for slow cooling routes and that most of the physical attributes are comparable to natural rock. Despite this, granodiorite thermal deterioration is substantially higher for quick cooling than for slow cooling. Between 400:600 °C is ‘the transitional stage’, where the physical and mechanical characteristics degraded exponentially for all cooling pathways. Independent of the cooling method, the granodiorite showed a ductile failure mode associated with reduced peak tensile strengths. Additionally, the microstructure altered from predominantly intergranular cracking to more trans-granular cracking at 600 °C. The integrity of the granodiorite structure was compromised at 800 °C, the physical parameters deteriorated, and the rock tensile strength was negligible. In this research, the temperatures of 400, 600, and 800 °C were remarked to be typical of three divergent phases of granodiorite mechanical and physical properties evolution. Furthermore, 400 °C could be considered as the threshold limit for Egyptian granodiorite physical and mechanical properties for typical thermal underground applications.

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Thermal, Physical and Mechanical Properties of Poly(Butylene Succinate)/Kenaf Core Fibers Composites Reinforced with Esterified Lignin

Polymers ◽

10.3390/polym13142359 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2359

Author(s):

Harmaen Ahmad Saffian ◽

Masayuki Yamaguchi ◽

Hidayah Ariffin ◽

Khalina Abdan ◽

Nur Kartinee Kassim ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Loss Modulus ◽

Physical And Mechanical Properties ◽

Weight Percent Gain ◽

Weight Percent ◽

Esterification Reaction ◽

Butylene Succinate ◽

Kenaf Core ◽

Modified Lignin

In this study, Kraft lignin was esterified with phthalic anhydride and was served as reinforcing filler for poly(butylene succinate) (PBS). Composites with different ratios of PBS, lignin (L), modified lignin (ML) and kenaf core fibers (KCF) were fabricated using a compounding method. The fabricated PBS composites and its counterparts were tested for thermal, physical and mechanical properties. Weight percent gain of 4.5% after lignin modification and the FTIR spectra has confirmed the occurrence of an esterification reaction. Better thermo-mechanical properties were observed in the PBS composites reinforced with modified lignin and KCF, as higher storage modulus and loss modulus were recorded using dynamic mechanical analysis. The density of the composites fabricated ranged from 1.26 to 1.43 g/cm3. Water absorption of the composites with the addition of modified lignin is higher than that of composites with unmodified lignin. Pure PBS exhibited the highest tensile strength of 18.62 MPa. Incorporation of lignin and KCF into PBS resulted in different extents of reduction in tensile strength (15.78 to 18.60 MPa). However, PBS composite reinforced with modified lignin exhibited better tensile and flexural strength compared to its unmodified lignin counterpart. PBS composite reinforced with 30 wt% ML and 20 wt% KCF had the highest Izod impact, as fibers could diverge the cracking propagation of the matrix. The thermal conductivity value of the composites ranged from 0.0903 to 0.0983 W/mK, showing great potential as a heat insulator.

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Influence of Hydrostatic Extrusion on the Mechanical Properties of the Model Al-Mg Alloys

Journal of Materials Engineering and Performance ◽

10.1007/s11665-021-05628-0 ◽

2021 ◽

Author(s):

Aleksandra Towarek ◽

Wojciech Jurczak ◽

Joanna Zdunek ◽

Mariusz Kulczyk ◽

Jarosław Mizera

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Tensile Strength ◽

Microstructural Analysis ◽

Tensile Tests ◽

Hydrostatic Extrusion ◽

Microstructure Formation ◽

Initial State ◽

Degree Of Deformation ◽

Al Mg Alloys

AbstractTwo model aluminium-magnesium alloys, containing 3 and 7.5 wt.% of Mg, were subjected to plastic deformation by means of hydrostatic extrusion (HE). Two degrees of deformation were imposed by two subsequent reductions of the diameter. Microstructural analysis and tensile tests of the materials in the initial state and after deformation were performed. For both materials, HE extrusion resulted in the deformation of the microstructure—formation of the un-equilibrium grain boundaries and partition of the grains. What is more, HE resulted in a significant increase of tensile strength and decrease of the elongation, mostly after the first degree of deformation.

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Effect of Castor Oil Impregnation on the Physical and Mechanical Properties of Bacterial Cellulose

Polymers from Renewable Resources ◽

10.1177/204124791200300102 ◽

2012 ◽

Vol 3 (1) ◽

pp. 13-26

Author(s):

Myrtha Karina ◽

Lucia Indrarti ◽

Rike Yudianti ◽

Indriyati

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Bacterial Cellulose ◽

Young’S Modulus ◽

Castor Oil ◽

Young's Modulus ◽

Physical And Mechanical Properties ◽

Scanning Electron Micrographs ◽

Elongation At Break ◽

Acetone Water

The effect of castor oil on the physical and mechanical properties of bacterial cellulose is described. Bacterial cellulose (BC) was impregnated with 0.5–2% (w/v) castor oil (CO) in acetone–water, providing BCCO films. Scanning electron micrographs revealed that the castor oil penetrated the pores of the bacterial cellulose, resulting in a smoother morphology and enhanced hydrophilicity. Castor oil caused a slight change in crystallinity indices and resulted in reduced tensile strength and Young's modulus but increased elongation at break. A significant reduction in tensile strength and Young's modulus was achieved in BCCO films with 2% castor oil, and there was an improvement in elongation at break and hydrophilicity. Impregnation with castor oil, a biodegradable and safe plasticiser, resulted in less rigid and more ductile composites.

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Composites from Thermoplastic Natural Rubber Reinforced Rubberwood Sawdust: Effects of Sawdust Size and Content on Thermal, Physical, and Mechanical Properties

International Journal of Polymer Science ◽

10.1155/2018/7179527 ◽

2018 ◽

Vol 2018 ◽

pp. 1-11 ◽

Cited By ~ 5

Author(s):

Chatree Homkhiew ◽

Surasit Rawangwong ◽

Worapong Boonchouytan ◽

Wiriya Thongruang ◽

Thanate Ratanawilai

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Natural Rubber ◽

High Density Polyethylene ◽

High Performance ◽

Physical And Mechanical Properties ◽

Modulus Of Rupture ◽

Shore Hardness ◽

Thermoplastic Natural Rubber ◽

Plastic Content

The aim of this work is to investigate the effects of rubberwood sawdust (RWS) size and content as well as the ratio of natural rubber (NR)/high-density polyethylene (HDPE) blend on properties of RWS reinforced thermoplastic natural rubber (TPNR) composites. The addition of RWS about 30–50 wt% improved the modulus of the rupture and tensile strength of TPNR composites blending with NR/HDPE ratios of 60/40 and 50/50. TPNR composites reinforced with RWS 80 mesh yielded better tensile strength and modulus of rupture than the composites with RWS 40 mesh. The TPNR/RWS composites with larger HDPE content gave higher tensile, flexural, and Shore hardness properties and thermal stability as well as lower water absorption. The TPNR/RWS composites with larger plastic content were therefore suggested for applications requiring high performance of thermal, physical, and mechanical properties.

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