Filler Material In Composites Research Articles

Enhancement of magnetic activation on the backfilling performance of coal gangue-based composite materials

ABSTRACT The large accumulation of coal gangue has resulted in significant environmental contamination and detrimental impacts. Utilizing it as a filler material in coal mining operations may successfully address this issue. It may be used to efficiently alleviate this issue by filling up coal mines. The wettability of magnetized solution on the coal gangue surface and the phase composition, microstructure, and pore structure of hydration products of coal gangue-based composite material (CGCM) at different ages were analyzed by means of contact angle (CA), X-ray diffraction (XRD), thermogravimetry (TG/DTG), mercury intrusion (MIP), and scanning electron microscopy (SEM) in order to control the fluidity and mechanical properties of backfilling materials. Simultaneously, an investigation was conducted on the slump expansion, setting time, and compressive strength of composite filler materials derived from magnetized coal gangue. The findings indicate that the application of a magnetic field reduces the interaction force among the molecules in the mixing water. Consequently, this leads to an improvement in the wettability of the coal gangue particle surface. Thus, the fluidity of the backfilling slurry is improved. The permeability and diffusion characteristics of magnetized water surpass those of regular water, The rate of dissolving and hydration reactions of the cementitious active material in the slurry is increased, resulting in a noticeable reduction in the setting time of the slurry. In the backfilling body, magnetized mixing water can encourage the formation of dicalcium silicate (C2S), tricalcium silicate (C3S), and Ca (OH)2. Higher amounts of C-S-H gel and Aft are produced by the pozzolanic action with SiO2, which enhances the pore structure. Thus, the mechanical qualities of the filler body are enhanced. The study findings provide novel insights into the coal gangue backfill mining and offer an environmentally friendly and efficient approach for the large-scale processing and exploitation of coal gangue.

Using Local Concentration to Model the Progress of Acoustophoretic Assembly of Microspheres in Planar Standing Waves

Abstract Acoustophoretic assembly uses a standing acoustic field to move dispersed small particles into a geometric pattern. The technique relies on the acoustic radiation force (ARF), which arises from the interaction between the acoustic field and the particles, and drives the particles toward the pressure nodes or antinodes of the standing wave. Acoustophoretic assembly shows potential for a wide range of applications, including organizing filler materials in composites, creating metamaterials, and fabricating functional biological tissue. However, the method has not yet been incorporated into large-scale manufacturing processes. One barrier is the incomplete understanding of the assembly process. While an ideal final pattern geometry can be calculated from the acoustic field and material properties, there are currently no widespread metrics for measuring the progress of the pattern formation. As a result, it is difficult to know how long the acoustic field should be applied during manufacturing. Our approach uses the local particle concentration to model the acoustophoretic assembly process in bulk acoustic waves. We show that the time-dependent local particle concentration can be derived from the force balance on the particles and a control volume analysis. The analysis is applied to microspheres in a planar standing wave, and an analytical expression is obtained, which yields a time parameter for pattern assembly and suggests a cutoff time. We then use the local concentration to define measurements for the quality of the assembled microsphere pattern. Experiments were carried out using polystyrene microspheres in a glycerol–water mixture to validate the theoretical results.

Resource Utilization Potential of Red Mud: A Study on the Micro-Mechanism of the Synergistic Effect of Multiple Solid Waste Filling Materials

Red mud (RM) is a common industrial byproduct that is characterized by high alkalinity, high pollution, and difficult utilization. In this paper, gangue (CG), flue gas desulfurization gypsum (FGD), and silicate cement (PC) were used to assist red mud in the preparation of red mud-based composite filler material (RMC), aiming at the large-scale resource utilization of RM. The effects of the mass ratio of RM/CG, the mass ratio of FGD/(RM + CG), and the water–solid ratio (WCR) on the multi-angle properties of RMC were investigated and the optimal ratios were determined. The results showed that the RM/CG was 7:1, FGD/(RM + CG) was 4%, and WCR was 0.51 (RMC8), and the system could increase the RM content to 70%. The microstructural analysis of RMC using a specific surface area and porosity analyzer (BET), X-ray diffractometer (XRD), and scanning electron microscope (SEM) showed that its hydration products could remodel the pore structure, encapsulate and cement the coarse and fine particles into a dense matrix, and play a certain alkali reduction role, which revealed the microscopic synergistic mechanism between multiple solid wastes. The study shows that the comprehensive disposal of RM reduces the pollution released into the environment and provides new ideas for the green development of mines.

Studying the influence of waste glass and montmorillonite powders on the thermal conductivity and hardness of poly(methyl methacrylate) polymer matrix

The present study aims to evaluate the effect of montmorillonite nanoclay (MMT) and waste glass powder (WGP) on the hardness and thermal conductivity of PMMA polymer composites. Thus, this study concentrates on the potential use of MMT and WGP as reinforcements, in different concentrations, in PMMA polymer matrix, with the expectation of improving the performance of PMMA polymer composites in various applications.There is a growing demand for PMMA with increased mechanical properties and thermal stability for applications where inorganic glass would fail. Montmorillonite (MMT) clay and Waste Glass Powder (WGP) have physical and chemical properties compatible with PMMA. Therefore, they could potentially enhance PMMAs hardness and thermal conductivity. Silicon dioxide in glass silica and MMT and octahedral aluminium hydroxide sheet in MMT can strengthen both covalent and hydrogen bonding architecture in PMMA composite for better mechanical strength and thermal conductivity. Thus, PMMA composites were designed by combining MMT powder and WGP powder in different ratios before being incorporated into the PMMA polymer matrix and tested for hardness and thermal conductivity.The present study measured Brinell Hardness (HB) and electrical conductivity values of four PMMA composites containing different proportions of MMT and WGP. MMT/WGP filler mix had optimal hardiness (HB number = 74) when glass content was 1% (3MMT1G) or better still (HB number = 63) when an equal mix ratio was used (1MMT1G). PMMA composite with 3MMT1G also had the highest thermal conductivity (0.01899W/m.K-1). However, the higher the glass content, the lower the thermal conductivity of the PMMA composite. Thus, the present study has demonstrated that 3MMT1G filler was the best for enhancing the thermal and mechanical properties of PMMA composite.The results of this study demonstrate the potential of this new composite material for a variety of applications. Further research is needed to explore the full potential of this material and to develop new and improved versions.Reusing waste glass as filler materials in composites requires minimal processing and therefore has lower environmental impacts than synthetic options.Experimental data from the present study has provided new insights into Glass/MMT mix design in PMMA composites. The PMMA composite containing 3MMT1G exhibited the best hardness and thermal conductivity characteristics. Thus, the present study has successfully optimised Glass/MMT mix design for PMMA composite for applications requiring these features.

Potential of Using Agricultural Waste Composites as Thermal Insulation Material

AbstractA huge amount of waste is produced every day in the world and it is thrown away without giving them any new use. Agricultural wastes generated as a result of obtaining, processing, and consuming plant and animal products constitute a remarkable large part of this waste amount. Today, these wastes are used in the production of composites, and the composites produced from these wastes give positive results in durability, flexibility, and thermal insulation. Composite materials which are combination of different materials to create a new material with discrete properties than its ingredients have gained great importance with the increment of product variety thus the property requirement. In production process, it is now always possible to fulfill the requirements of the design with conventional engineering materials. Since composite materials have the ability of being tailorable they have been started to be used in many different application areas. Recently, the usage of such composite materials in the automotive field has been evaluated. In this review, the usage of composites produced from different agricultural wastes in thermal insulation has been examined. A detailed review of the past and recent research activities has been documented. The literature survey reveals that agricultural wastes can be a good candidate to be used as reinforcement or filler material in composites for thermal insulation purposes.

Experimental Investigation on Thermal Behaviors of Nanosilicon Carbide/Kenaf/Polymer Composite

Over the last few years, natural fiber-based hybrid polymers have been widely used to increase the biodegradability and cost-effectiveness of the products in many industrial applications, such as automobile construction industries. Adding filler materials provides enhanced wear properties and thermal behaviors of composites. Kenaf fiber has better strength and stiffness, and it has been used as reinforcement in polymer composites. Silicon carbide as filler material in composites modifies the mechanical properties and thermal behaviors. The present research analyzes the thermal characteristics of silicon carbide/kenaf fiber-reinforced epoxy composites with various weight percentages. Six different composite specimens were fabricated at varying weight percentages of silicon carbide. The specimens were subjected to various thermal tests, such as heat deflection temperature (HDT), coefficient of thermal expansion (CTE), thermal conductivity (TC), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The findings could serve to expand the range of application for SiC/kenaf fiber-reinforced composite, which may have better thermal stability, better performance, and lower thermal expansion than the other regularly used natural fiber-reinforced composites.

Effect of aspect ratio on piezo-resistance properties of aligned multi-walled carbon nanotube polymer composites

Multi-walled carbon nanotubes (MWNTs) are actively used as reinforcing and electrical filler materials in composites owing to their superior electrical and mechanical performances. The electrical, mechanical, and piezoresistive performances of MWNT/polymer composites vary depending on the filler direction and aspect ratio (A/R). In this study, we fabricated MWNT/polymer composites with fillers aligned at different A/R. To prepare the aligned MWNT polymer composite with three different A/R, well dispersed MWNTs in the polymer matrix were applied continuous shear force in one direction by two-roll mill. Also, randomly oriented composites using same fillers were compared their mechanical, electrical, and piezoresistive properties to aligned composites. The aligned composite with the high A/R showed 6.03 times higher in elastic modulus and 17.4 times higher in electrical conductivity compared to the randomly oriented composite with the low A/R. The piezo-resistance, expressed as the maximum resistance change in tension, of the aligned composite with the low A/R had 84% higher than that of the randomly arrayed composite with the high A/R. In contrast to the enhancement of mechanical and electrical properties as the A/R rises and alignment occurs, the resistance in tension increases as the A/R decreases and the fillers are aligned. Thus, the influence of the filler alignment on the piezo-resistance properties of the composite is significant.

Potential end of life application of African star apple shell and waste toner powder as composite filler materials

Potential end of life application of African star apple shell and waste toner powder as composite filler materials

Forming a conductive large area AA6061 HDPE metal-polymer composite via top plate friction stir processing

In this study, a new method of forming conductive large area metal/polymer composites called top plate friction stir processing was performed using a thin aluminum plate and HDPE sheet. To form the composite, a rotary tool uses friction to heat and stir lapped aluminum into HDPE. This method differs from other forms of friction stir processing polymers because the base material does not need modification prior to processing, increasing the total manufacturing efficiency. Upon processing, the top plate becomes the composite filler material in addition to controlling surface quality by containing the molten polymer and distributing heat. Optical analysis, electrical and thermal conductivity tests, and tensile tests were performed to determine the material distribution, conductivity, and mechanical properties of processed specimens. These tests revealed that top plate friction stir processing improved the electrical and thermal conductivity over the base HDPE. Electrical resistance across specimens measured just several ohms and thermal conductivity increased up to 108%, but mechanical properties have room for improvement.

Fillers for aesthetics on the face – Newer perspectives

Dermal fillers are a cornerstone of the aesthetic treatments of the face. They have evolved over many aspects since their initial use. Facial fillers are not just used for anti-aging to restore volume, but are now also used for contouring, enhancing facial features, and changing the emotional attributes of the face. Newer techniques and approaches have been proposed for greater predictability of results and minimum complications. Newer composite filler materials and a resurgence of older materials have taken place with better understanding of the science behind them. With more use of facial fillers comes the reporting of newer complications with recommendations and guidelines to avoid them. A new perspective is seen in guidelines for their use in the COVID-19 pandemic. This article is a review of the insight into the latest perspectives of facial fillers for aesthetic indications.

A review on filler materials for brazing of carbon-carbon composites

Abstract It is needed to join C/C composite to other materials since its individual use is limited. Brazing is a method to join C/C composite that has been studied most, maturest and most widely used in recent decades. The quality of a brazed joint is largely determined by the intermediate layer material. It is significant to choose filler materials reasonably. C/C composite is difficult to be wetted by common brazing filler materials. Moreover, there is a large difference in the coefficient of thermal expansion between C/C composite and metals. At present, there is no brazing filler alloy exclusively recommended for commercial C/C composites and metal brazing. Usually, active elements are added into filler metals to improve the wettability of them on C/C composite surface. The existing research includes Al-based, Ag-based, Cu-based, Ti-based, Ni-based brazing filler metals, and so on. In addition, various particle reinforced composite filler materials and stress buffer metal interlayer added composite filler materials have been studied for brazing C/C composite. The summarization of the overview on the application of intermediate filler metals is made in this paper. The basic reference basis is provided for the subsequent brazing filler metals development and joint performance improvement for C/C composite brazing.

Innovative processes of production functional gradient layered compositions with enhanced tribological properties

Arc surfacing processes are proposed as innovative methods for the synthesis of functionally gradient layered compositions. Existing composite filler materials based on aluminum and tin have been investigated. The schemes and technological parameters of arc welding allowing to produce the coatings having a composite structure with a given reinforcement ratio, satisfactory reinforcements distribution, and enhanced tribotechnical properties have been shown.

Composite brazing of C/C composite and Ni-based superalloy using (Ag-10Ti)+TiC filler material

With the aim of alleviating the residual thermal stress in the C/C-GH3044 joints, a novel composite brazing, which combines Ag-Ti reactive composite brazing and TiC particle-reinforced composite brazing, was adopted for joining C/C composite to Ni-based superalloy GH3044 using (Ag-10Ti)+TiC composite filler material. The results showed that the composite interlayer was strengthened by four kinds of reinforcements, containing the introduced TiC, the in situ synthesized AgTi and Ti 2 Ni phases, and the residual Ti particles. With increasing TiC content from 0 to 32 %, the thermal expansion coefficient of the composite interlayer declined by 18.2 %, which is helpful in alleviating the residual thermal stress in the joints. In addition, the introduced TiC particles decreased the fluidity of the filler material and inhibited the inter-diffusion of atoms between GH3044 and filler material. As a result, the continuous brittle compound Ti 2 Ni in the composite interlayer was effectively reduced, so the composite interlayer had good plasticity. Meanwhile, the thickness of the composite interlayer gradually increased from 260 μm to 520 μm, and the finite element analysis showed that the corresponding peak value of von Mises stress decreasedby 20.1 %. The highest shear strength of the joints was 67.2 MPa obtained with (Ag-10Ti)+24 %TiC at 1020°C for 30 min,which is almost the same strength as the C/C composite matrix used in this study.

Fabrication of high density polyethylene composites reinforced with pine cone powder: mechanical and low velocity impact performances

The pine cone plant is a cellulosic material that is inexpensive and abundant in nature. It can be used as a reinforcing material in thermoplastic based composites. Pine cone plant has good mechanical properties and therefore allows it to be used as a filler material in composites. Alternative utilization from such agricultural pine cone powder in high density polyethylene (HDPE) composites can supply economic and environmental advantages. In this study, pine cone reinforced high density polyethylene (HDPE) composites were fabricated and their mechanical (i.e., tensile, compression and flexural properties) and low velocity impact behaviors were determined experimentally. To this end, collected pine cones were firstly cut into 1 cm pieces by using a knife and were pulverized by grinding in a ring mill. After that, two HDPE plates with dimensions of 350 × 350 × 1 mm were manufactured in the hot press. Then, various percentage amounts of powdered pine cones (5, 10, 15 and 20% wt) were added between these plates. Thereafter, pine cone reinforced HDPE composites were obtained under the same conditions. Mechanical properties and low velocity impact behaviors of the pine cone reinforced HDPE composites were determined at room temperature and findings were compared with each other. The parameters such as tensile and flexural strengths, compressive strength, elasticity and flexural modulus and energy absorption capacities of the composites were evaluated through various curves. According to obtained results, HDPE containing 10% pine cone powder showed the highest tensile strength, elasticity modulus and flexural strength. Low velocity impact test results exhibited that maximum contact force values of the reinforced HDPE with 5, 10 and 15% wt pine cone powder are higher than the neat HDPE at the impact energy levels ranging from 5 J to 25 J.

Improved Dynamic Characteristics for Machine Tools Structure Using Filler Materials

Simplified filler approach has been developed to enhance structural stability of existing cast iron columns and beds. The motivation for this research was to develop a machine tool structural material having characteristics such as, improved dynamic stability, ease in production, cost-effectiveness, and sustainability. A methodology has been developed to predict dynamic behaviour of prototype column structure using simplified reduced odd-scale model. A combination of formulae based similitude model, FE based structural analysis and statistics based Taguchi design analysis has been used to achieve enhanced structural dynamic performance of a VMC column. Similitude principles have been developed to correlate simplified odd-scale column model with existing complex prototype column through FE based 1:5 scaled column structure. Prototype column has been replaced by simplified odd-scale column for filler optimization experiments using Taguchi design and scaling factors. Simplified odd-scale column models were filled with a number of combinational designs of unique composite filler material. VMC column structural stability in terms of excitation decay time, dynamic stress and displacement has been analyzed for present hollow cast iron structures as well as filled structures. Present methodology combination reduces efforts to develop dynamically improved machine tool structures through simplified odd-scale models, avoiding complexity involved in implementation of traditional scaling approach. As a result, dynamic characteristics have been improved by 20-30 times with introduction of composite filler material as compared to unfilled structures. This composite filler technology has been applied for patent.

Joining interface and compressive strength of brazed cubic boron nitride grains with Ag-Cu-Ti/TiX composite fillers

Ag-Cu-Ti/TiX (TiX=TiB2, TiN or TiC) composite filler materials, instead of pure Ag-Cu-Ti alloy, were developed to improve the comprehensive mechanical performance of brazed joints of cubic boron nitride (CBN) grains/bonding layer/steel matrix. This article mainly concerns the effects of TiX addition on the joining interface and compressive strength of brazed CBN grains. The results demonstrate that, due to the variation of chemical activity of Ti atoms induced by TiX addition into the brazing system, the brazing reactions, especially chemical resultants produced at the joining interface between CBN grain and Ag-Cu-Ti alloy, are restrained to some extents. In general, the TiN particles show the greatest suppression effect on the brazing resultants, while the TiC particles have the weakest effect, and TiB2 particles have the medium effect. The optimum reinforcement of the composite filler is finally determined as the TiB2 particles with the content of 8wt%, with which the average compressive strength of brazed CBN grains reaches 15 N, which is nearly the same high as that of original CBN grains.

Brazing of CBN grains with Ag-Cu-Ti/TiX composite filler - The effect of TiX particles on microstructure and strength of bonding layer

In order to improve the comprehensive mechanical performance of brazed joints of cubic boron nitride (CBN) grains/bonding layer/steel matrix, Ag-Cu-Ti/TiX (TiX=TiB2, TiN or TiC) composite filler materials, instead of the pure Ag-Cu-Ti alloy, were developed. As Part I of this work, a detailed investigation on the effects of TiX addition on the microstructure and strength of Ag-Cu-Ti/TiX bonding layer was made based on the evaluation of some fundamental performance (i.e. spreading area, shear strength, metallurgical microstructure and microhardness). Results obtained indicate that, the addition of TiX particles to Ag-Cu-Ti alloy is generally favorable for controlling the spreading behavior and improving the shear strength and microhardness of bonding layer. The metallurgical microstructure of the Ag-Cu-Ti/TiX bonding layer is refined to a certain extent, which is contributed to that the added particles become the potential nucleation agent of the molten Ag-Cu-Ti alloy during brazing. Combined with the effects of the reinforcing particles on the comprehensive performance of the bonding layer, and meanwhile considering the effects of the reinforcing particles on the brazing resultants of CBN grains reported in Part II of this work, the optimum addition to the Ag-Cu-Ti/TiX composite filler materials is determined as the TiB2 particles with 8wt.% content.

Composite Materials Reinforced with Fabric from Used Tyres

The Paper deals with testing of composite materials reinforced with fabric, which are obtained after the recycling process of used tyres and matrix is polyvinyl butyral (PVB). PVB is a product of windshields recycling. Fabric, that makes up the composite filler material benefits in various proportions of polyvinyl butyral, which is a matrix of the composite. It is possible to produce various designs material with percentage from 1 % to the 80% of fabrics. The advantage of this material is the primary resource conservation, the use of recovered (waste) materials, and thus generally contributes to environmental protection.

The influence of accelerated weathering on the mechanical and physical properties of wood-plastic composites

This research concentrates on the effect of moisture absorption and UV radiation on the mechanical and physical properties of wood-plastic composites (WPC). The goal is also to evaluate the importance of wood flour fraction size on the mechanical properties of WPC and their influence on the accelerated weathering results. Wood flour reinforced composites with three different fractions of wood flour made from birch (Betula) chips were prepared. Additionally, Bleached-Chemi-Thermo- Mechanical aspen (Populus tremula) pulp (Aspen BCTMP) was used. Thermoplastics (LLDPE-g-MAH, PP) were used to prepare composites. Wood flour and BCTMP surface were treated with two different coupling agents: 3-aminopropyltriethoxysilane (APTES) and polyvinyalcohol (PVA). The WPC specimens were prepared by injection molding. Accelerated weathering tests were carried out to evaluate the influence of weathering on the mechanical and physical properties of composites. Three-point bending test and Charpy impact test were used to test mechanical properties. The test results showed that using wood flour as a filler material in composites made the WPC material more rigid and brittle. Due to the water absorption and swelling of WPC, the flexural modulus (MOE) and strength decreased and impact strength increased by making the material weaker with increasing the deflection of the WPC. The UV radiation decreased the composites flexural strength and MOE, while impact strength was increased. After the accelerated weathering cycles, cracks and voids were found on the surface of the WPC materials. After the UV radiation treatment, also the WPC colour was lightened.

Microstructures and mechanical properties of Cf/SiC composite and TC4 alloy joints brazed with (Ti–Zr–Cu–Ni)+W composite filler materials

Abstract In this study, carbon fiber reinforced SiC (Cf/SiC) composite was joined to TC4 alloy using (Ti–Zr–Cu–Ni)+W mixed powders as composite filler material at proper process parameters. The interfacial microstructures and evolution mechanism of Cf/SiC composite/(Ti–Zr–Cu–Ni)+W/TC4 alloy joints were investigated based on scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). The mechanical properties of the brazed joints were measured by the mechanical testing machine. The results showed that Ti and Zr elements in the interlayer can react with the brazed material, the brazed joint mainly consisted of Ti3SiC2, Ti5Si3, (Ti, Zr)C, Ti2Cu, Cu10Zr7, Ti(Cu, Ni) and Ti(s,s) reaction products. The diffusion–reaction layer was formed between the interlayer and TC4 alloy due to the element interdiffusion. The brazing parameters had a distinct effect on the interfacial reaction between Cf/SiC composite and filler material, which affected the shear strength of the brazed joints. Adding the appropriate W powder was beneficial for relaxing the residual thermal stress and reinforcing the brazed joints. The maximum shear strength of the brazed joints was 166 MPa at room temperature and 96 MPa at 800 °C high temperature acquired at 930 °C for 20 min using (Ti–Zr–Cu–Ni)+15 vol.%W composite filler material.