mechanical properties

Chemical regeneration of thermally conditioned basalt fibres

The disposal of fibre reinforced composite materials is a problem widely debated in the literature. This work explores the ability to restore the mechanical properties of thermally conditioned basalt fibres through chemical treatments. Inorganic acid (HF) and alkaline (NaOH) treatments proved to be effective in regenerating the mechanical strength of recycled basalt fibres, with up to 94% recovery of the strength on treatment with NaOH.

Waste polymer addition for 3D cementitious printing materials

Background/ Objectives and Goals
During the last 30 years, extensive researches were performed an attempt to reuse the waste tires by grinding them into granulated samples and use
as aggregates in cementitious materials. The innovative purpose of this work is to investigate the feasibility of applying tire rubber-modified cement
compounds to 3D additive construction technologies. The influence of crumb rubber on the rheological, durability and structural performance of

Nanomechanical characterization of K-basalt from Roman comagmatic province: A preliminary study

Based on atomic force microscopy (AFM), contact resonance AFM (CR-AFM) is a nondestructive technique that allows
one to perform single point measurements as well as surface mapping of the indentation modulus of a material. In this work we
exploit the possibility to use CR-AFM to study synthetic materials representative of K-basalt from Roman comagmatic Province.
Having observed the presence of subsurface voids and inclusions at micrometer and sub-micrometer scale, a preliminary study has

Quasi-static and low-velocity impact behavior of intraply hybrid flax/basalt composites

In an attempt to increase the low-velocity impact response of natural fiber composites, a new hybrid intraply woven fabric based on flax and basalt fibers has been used to manufacture laminates with both thermoplastic and thermoset matrices. The matrix type (epoxy or polypropylene (PP) with or without a maleated coupling agent) significantly affected the absorbed energy and the damage mechanisms. The absorbed energy at perforation for PP-based composites was 90% and 50% higher than that of epoxy and compatibilized PP composites, respectively.

Hybrid cellulose–Basalt polypropylene composites with enhanced compatibility. The role of coupling agent

This study deals with the development and optimization of hybrid composites integrating microcrystalline cellulose and short basalt fibers in a polypropylene (PP) matrix to maximize the mechanical properties of resulting composites. To this aim, the effects of two different coupling agents, endowed with maleic anhydride (MA-g(grafted)-PP) and acrylic acid (AA-g-PP) functionalities, on the composite properties were investigated as a function of their amount.

Tailoring the interfacial strength of basalt fibres/epoxy composite with ZnO-nanorods

The presence of a secondary phase between the fibres and the matrix has proved to be a good approach for interphase tailoring for enhanced load transfer. In this regard, an optimization of the low-temperature hydrothermal growth process of ZnO-nanorods on different basalt substrates as a function of different growth times was performed. Scanning electron microscope and X-ray diffraction analysis revealed the best results in terms of homogeneity and uniformity of the ZnO nanostructures for the longest growth time, i.e., 5 h for basalt fabrics and 120 minutes for single basalt fibres.

Correlation between mechanical properties and processing conditions in rubber-toughened wood polymer composites

The use of wood fibers is a deeply investigated topic in current scientific research and one of their most common applications is as filler for thermoplastic polymers. The resulting material is a biocomposite, known as a Wood Polymer Composite (WPC). For increasing the sustainability and reducing the cost, it is convenient to increase the wood fiber content as much as possible, so that the polymeric fraction within the composite is thereby reduced.

Interactions between PLA, PE and wood flour. Effects of compatibilizing agents and ionic liquids

The differences in hydrophilicity are a main drawback for wood polymer composites (WPCs). This work aims at compatibilizing bio-derived poly(lactic acid) (PLA), high density polyethylene (PE) and wood fibers (WFs) with either functional PEs [PE-graft-maleic anhydride (MA) (Polybond 3029) or random copolymer of ethylene and glycidyl methacrylate (PE-g-GMA) (Lotader AX8840)] or trihexyl(tetradecyl)phosphonium bistriflamide ionic liquid (IL). The interactions and possible chemical reactions between PLA and functional PE or IL were studied including their mechanical properties.

Influence of thermal conditioning on tensile behaviour of single basalt fibres

This article presents an experimental investigation of the effects of temperature and atmosphere on the tensile behaviour of basalt fibres. The heating conditions have been chosen in order to mimic those used in thermal recycling of polymer matrix composites. The change of properties is investigated at room temperature on fibres heat-treated for 1 h up to 600 °C in air and in inert atmosphere (argon).

Comparison between mechanical properties and structures of a rolled and a 3D-printed stainless steel

In this work selective laser melting was successfully utilized to produce 316 stainless steel bulk specimens. Although this technology provides many advantages compared to conventional shaping processes, little residual porosity may be a problem for some applications where high strength is required. The objective of this work was to determine, through data analysis, a mechanical and metallographic comparison between thin sheets made by using different manufacturing technologies: Cold rolling and additive manufacturing.

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