scholarly journals Tribological Behavior of a Rubber-Toughened Wood Polymer Composite

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2055
Author(s):  
Valentina Mazzanti ◽  
Annalisa Fortini ◽  
Lorenzo Malagutti ◽  
Giulia Ronconi ◽  
Francesco Mollica
Keyword(s):  
Environmental Sustainability ◽  
Tribological Behavior ◽  
Wood Flour ◽  
Thermal Analyses ◽  
Constant Load ◽  
Dry Sliding Wear ◽  
Damping Factor ◽  
Wood Polymer ◽  
Pre Treatment ◽  
Toughening Agent

Wood polymer composites or WPCs are increasingly used as substitutes for natural wood in outdoor applications due to their better environmental sustainability and the consequent reduction in carbon footprint. In this paper, the presence of an elastomer used as a toughening agent (Santoprene by Exxon Mobil) in a polypropylene-based WPC containing 50 wt % wood flour was investigated in terms of its tribological behavior by dry sliding wear tests. These were performed after two environmental pre-conditioning treatments, i.e., drying and water soaking. The ball-on-disk configuration under a constant load was chosen along two sliding distances. Dynamic mechanical thermal analyses were used to reveal the effect of the toughening agent on the storage modulus and damping factor of the composites. Results in terms of weight loss measurement and coefficient of friction were obtained, together with surface morphology analysis of the worn surfaces at the scanning electron microscope and 3D profilometer. An abrasive wear mechanism was identified, and it was shown that the toughening agent improved wear resistance after both pre-treatments. This beneficial effect can be explained by the increase in strain at break of the WPC containing the elastomer. On the other hand, the water soaking pre-treatment produced severe damage, and the loss of material cannot be completely compensated by the presence of the toughening agent.

scholarly journals Biofilm on the polymer composites - qualitative and quantitative microbiological analysis

2021 ◽  
Author(s):  
Dobrochna Ginter-Kramarczyk ◽  
Izabela Kruszelnicka ◽  
Michał Michałkiewicz ◽  
Przemysław Muszyński ◽  
Stanisław Zajchowski ◽  
...  
Keyword(s):  
Polymer Composites ◽  
Wood Flour ◽  
Biological Membrane ◽  
Polymeric Materials ◽  
Active Surface ◽  
Modern Technology ◽  
Biofilm Reactor ◽  
Active Surface Area ◽  
Microbiological Analysis ◽  
Wood Polymer

Abstract Background Modern technology, which has been getting more and more recognition in the world for the last several years, is the moving bed biofilm reactor (MBBR) technology. Currently, movable biofilters made of basic polymeric materials, polyethylene and polypropylene. Methods An innovative solution in the field, mainly because of the large active surface area for biological membrane can be wood polymer composites (WPC). In the research polypropylene (PP) and polyvinyl chloride (PVC) was used as the matrix. Two types of commercial wood flour also, selected from conifers, were selected for the study: Lignocel C 120 with particle sizes in the range of 70 μm–150 μm and L9 with dimensions of 0.8–1.1 mm and wood chips, which are used on an industrial scale for the production of chipboards, were used as a filler. A quantitative and qualitative analysis of newly formed biofilms was performed. Results The study showed a direct effect of the filler and its particle size on the susceptibility to the formation of the biofilm of on the composites surface. Conclusions Polypropylene PPH 648 T and 40% wt. of L9 type wood flour was the most susceptible to biofilm formation. Pure polypropylene PPH 648 T was the least susceptible material.

Influence of wood flour loading on tribological behavior of epoxy composites

2008 ◽  
Vol 29 (11) ◽  
pp. 1189-1192 ◽  
Author(s):  
U.K. Dwivedi ◽  
Navin Chand
Keyword(s):  
Tribological Behavior ◽  
Wood Flour ◽  
Epoxy Composites

Fabrication and Tribological Properties of Al-Si/B4C Metal Matrix Composites

2014 ◽  
Vol 2 (1) ◽  
pp. 74-84 ◽  
Author(s):  
Sadineni Rama Rao ◽  
G. Padmanabhan ◽  
P.V. Chandra Shekar Rao
Keyword(s):  
Friction Coefficient ◽  
Boron Carbide ◽  
High Strength ◽  
Casting Process ◽  
Stir Casting ◽  
Constant Load ◽  
Dry Sliding Wear ◽  
Al Alloy ◽  
Wear Rates ◽  
Line Wear

Aluminium composite materials are exponentially growing up and rapidly gaining importance because of their properties like low density, high strength, high stiffness, environmental resistance, low co-efficient of thermal expansion etc. In this context aluminum-boron carbide composites, with 2.5, 5 and 7.5 wt% of boron carbide (B4C) particulate reinforced, were prepared by stir casting process and the effect of the percentage of reinforcement of B4C on dry sliding wear and friction coefficient were investigated. The wear tests were carried out on a pin-on-disc type apparatus at a linear speed of 1m/s, sliding distance of 500 m and a constant load of 30 N. The coefficient of friction was recorded on line. Wear rates were calculated from mass loss measurements. Scanning electron microscope was used to examine the tribo-surface of worn Al- B4C composites. The results showed that the wear rate of 7.5 wt% B4C composites is 0.375 mg/min which is significantly lower than pure Al alloy (3.125 mg/min). The friction coefficient decreases from 0.477(for pure Al alloy) to 0.261(for 7.5 wt% B4C composites).

scholarly journals Partial deoxygenation of biomass derived pyrolysis liquids

2018 ◽  
Vol 61 ◽  
pp. 00018
Author(s):  
Murlidhar Gupta ◽  
Jacques Monnier ◽  
Eric Turriff ◽  
Mark Boyd
Keyword(s):  
Environmental Sustainability ◽  
Capital Investment ◽  
High Pressures ◽  
Positive Impact ◽  
Biomass Pyrolysis ◽  
High Oxygen Content ◽  
Bio Oil ◽  
Pre Treatment ◽  
Lower Energy Density ◽  
Pyrolysis Liquids

Biomass pyrolysis liquids (also known as bio-oil), are derived from renewable lignocellulosic biomass residues by fast pyrolysis process. These second-generation oxygenated hydrocarbon resources have the potential to partially substitute for petroleum-derived feedstocks and thus enhance the economic and environmental sustainability of our natural resources. However, in contrast to petroleum fuels, biomass-derived pyrolysis liquids contain a large amount of oxygen, usually 40-50% wt% (wet basis). This undesirable high oxygen content in pyrolysis liquids is considered as the primary reason for its high polarity, high acidity, lower stability, lower energy density and very low miscibility with conventional crude refining feedstocks. There are two major pathways for upgrading the pyrolysis liquids. While hydrodeoxygenation route is one of the most explored options, it requires production and supply of large amounts of expensive hydrogen at high pressures, mandating large and centralized upgrading plants, and thus large capital investment. In this paper, we discuss an alternative method of pyrolysis liquid upgrading, using cheap and affordable hydrogen donor additives and catalysts to promote partial deoxygenation at near atmospheric pressure. This approach is preferably to be used as a pre-treatment and stabilizing method for pyrolysis liquids in the close vicinity of remote biomass pyrolysis plants. The pre-treated oil, then can be shipped for further hydrocracking process in a centralized co-processing facility. Preliminary results from the initial proof of concept experiments involving a 200 g/h gas-phase continuous fast catalytic cracking system with continuous coke removal to enhance deoxygenation performance are presented. These results indicate positive impact of catalyst bed on quality and yield of the upgraded bio-oil product in terms of pH, viscosity, degree of deoxygenation, oil yield and concentration of hydrogen in the off gases.

scholarly journals Germination and performance of seven native wildflowers in the Mediterranean landscape plantings

2017 ◽  
pp. 163-171 ◽  
Author(s):  
Enrico Scarici ◽  
Roberto Ruggeri ◽  
Maria Elena Provenzano ◽  
Francesco Rossini
Keyword(s):  
Environmental Sustainability ◽  
Native Species ◽  
Climatic Conditions ◽  
Mediterranean Environment ◽  
Seed Collection ◽  
Marginal Areas ◽  
The Mediterranean ◽  
Pre Treatment ◽  
And Performance ◽  
The Aesthetic

The use of native species in landscape design is a choice related to environmental sustainability and it contributes to the aesthetic appeal of urban and marginal areas. However, to date, the lack of knowledge of the ecological characteristics and agronomic practices of these species, represents a limit for their use. This study aims to obtain information about germination ecology, morphological traits and ornamental value of 7 selected perennial native taxa, with potential use in meadows seed mixtures for the Mediterranean environment. Seed germination for each taxon was assessed under different conditions (temperature, photoperiod and pre-treatment) in a controlled environment, while data on plant performances was collected from field plots. In general, the dormant seeds showed a positive response to pre-treatment with gibberellic acid (GA3) and chilling within a period of about six months from the time of seed collection. The dependence of germination on light and temperature was observed in most of the tested taxa. Differences in plant height and flowering dynamics gave practical directions in terms of combining seeds of different species to create and maintain a wildflower meadow in low-maintenance areas. Crepis bursifolia L. and Hypochaeris radicata L. were the only two species, which showed good persistence during the two-year field study and met the aesthetic requirements of low-input Mediterranean landscaping. Our study by adding original findings to the limited knowledge available on wildflower sowing in the Mediterranean environment, contributes to the development of sustainable strategies in the greening projects designed for those peculiar climatic conditions.

scholarly journals Surface, Subsurface and Tribological Properties of Ti6Al4V Alloy Shot Peened under Different Parameters

Materials ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 4363
Author(s):  
Yasemin Yıldıran Avcu ◽  
Okan Yetik ◽  
Mert Guney ◽  
Eleftherios Iakovakis ◽  
Tamer Sınmazçelik ◽  
...  
Keyword(s):  
Tribological Properties ◽  
Biomedical Applications ◽  
Sliding Wear ◽  
Tribological Behavior ◽  
Ti6al4v Alloy ◽  
Dry Sliding Wear ◽  
Micro Cracks ◽  
The Coefficient Of Friction ◽  
Mechanical Surface ◽  
Wear Tests

Ti6Al4V alloy was shot peened by using stainless-steel shots with different sizes (0.09–0.14 mm (S10) and 0.7–1.0 mm (S60)) for two durations (5 and 15 min) using a custom-designed peening system. The shot size was the main parameter modifying the roughness (0.74 µm for S10 vs. 2.27 µm for S60), whereas a higher peening time slightly increased roughness. Hardness improved up to approximately 35% by peening with large shots, while peening time was insignificant in hardness improvement. However, longer peening duration with large shots led to an unwanted formation of micro-cracks and delamination on the peened surfaces. After dry sliding wear tests, the mass loss of peened samples (S60 for 15 min) was 25% higher than that of un-peened samples, while the coefficient of friction decreased by 12%. Plastically deformed regions and micro-scratches were observed on the worn surfaces, which corresponds to mostly adhesive and abrasive wear mechanisms. The present study sheds light on how surface, subsurface and tribological properties of Ti6Al4V vary with shot peening and peening parameters, which paves the way for the understanding of the mechanical, surface, and tribological behavior of shot peened Ti6Al4V used in both aerospace and biomedical applications.

Tribological Behavior of Al–20Si–5Fe–2Ni Alloy at Elevated Temperatures Under Dry Sliding

2018 ◽  
Vol 140 (3) ◽  
Author(s):  
Hui Tan ◽  
Jun Cheng ◽  
Shuai Wang ◽  
Shengyu Zhu ◽  
Yuan Yu ◽  
...  
Keyword(s):  
Elevated Temperatures ◽  
Tribological Behavior ◽  
Wear Behavior ◽  
Dry Sliding Wear ◽  
Dry Sliding ◽  
Sintered Alloy ◽  
Aisi 52100 ◽  
Potential Applications ◽  
Aisi 52100 Steel ◽  
Worn Surface

Wear-resistant aluminum alloys have enormous potential applications. In this paper, the Al–20Si–5Fe–2Ni alloy was fabricated by hot-pressed sintering, and its dry sliding wear behavior was investigated from 25 °C to 500 °C sliding against Al2O3 ceramic and AISI 52100 steel. The microstructure, phase, high temperature hardness, and worn surface of the sintered alloy were examined. The results indicate that the uniform distribution of Si particles and Al5FeSi intermetallic in the Al matrix contribute to its superior tribological properties. Additionally, the correlation of the tribological behavior of the alloy with the sliding testing conditions was studied, and its wear mechanism was discussed.

Influence of Tempering Temperature and Microstructure on Wear Properties of Low Alloy PM Steel with 1-2 % Ni Addition

2007 ◽  
Vol 534-536 ◽  
pp. 629-632
Author(s):  
Süleyman Tekeli ◽  
Ahmet Güral ◽  
Metin Gürü
Keyword(s):  
Sliding Wear ◽  
Wear Behavior ◽  
Constant Load ◽  
Dry Sliding Wear ◽  
Dry Sliding ◽  
Wear Properties ◽  
Wear Coefficient ◽  
Tempering Temperature ◽  
Pin On Disk ◽  
Cold Pressed

The effect of tempering temperature and microstructure on dry sliding wear behavior of quenched and tempered PM steels was investigated. For this purpose, atomized iron powder was mixed with 0.3 % graphite and 1-2 % Ni powders. The mixed powders were cold pressed and sintered at 1200°C. The sintered specimens were quenched from 890°C and then tempered at 200°C and 600°C for 1 hr. Wear tests were carried out on the quenched+tempered specimens under dry sliding wear conditions using a pin-on-disk type machine at constant load and speed. The experimental results showed that the wear coefficient effectively increased with increasing tempering temperature. With increasing Ni content, the wear coefficient slightly decreased at all tempering temperatures due to the high amount of Ni-rich austenitic areas.

Effect of Repeated Quenching Heat Treatment on Microstructure and Dry Sliding Wear Behavior of Low Carbon PM Steel

2007 ◽  
Vol 534-536 ◽  
pp. 673-676 ◽  
Author(s):  
Ahmet Güral ◽  
Süleyman Tekeli ◽  
Dursun Özyürek ◽  
Metin Gürü
Keyword(s):  
Heat Treatment ◽  
Sliding Wear ◽  
Volume Fraction ◽  
Wear Behavior ◽  
Constant Load ◽  
Dry Sliding Wear ◽  
Dry Sliding ◽  
Low Carbon ◽  
Ar Gas ◽  
Pin On Disk

The effect of repeated quenching heat treatment on microstructure and dry sliding wear behavior of low carbon PM steel was investigated. For this purpose, atomized iron powder was mixed with 0.3 % graphite and 1 % Ni powders. The mixed powders were cold pressed and sintered at 1200°C for 30 min under pure Ar gas atmosphere. Some of the sintered specimens were intercritically annealed at 760°C and quenched in water (single quenching). The other sintered specimens were first fully austenized at 890°C and water quenched. These specimens were then intercritically annealed at 760°C and re-quenched in water. The martensite volume fraction in the double quenched specimens was higher than that of the single quenched specimen. Wear tests were carried out on the single and double quenched specimens under dry sliding wear condition using a pin-on-disk type machine at constant load and speed. The experimental results showed that the wear coefficient effectively decreased in the double quenched specimen.

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