Evaluation Of Mechanical Properties Research Articles

Hybrid Coatings Based on Polyvinylpyrrolidone/Polyethylene Glycol Enriched with Collagen and Hydroxyapatite: Incubation Studies and Evaluation of Mechanical and Physiochemical Properties.

Coating materials offers an intriguing solution for imparting inert implants with additional bioactive characteristics without changing underlying parameters such as mechanical strength. Metallic implants like endoprostheses or polymeric implants can be coated with a thin layer of bioactive film capable of stimulating bone-forming cells to proliferate or release a drug. However, irrespective of the final implantation site of such a coating biomaterial, it is necessary to conduct detailed mechanical and physicochemical in vitro analyses to determine its likely behavior under biological conditions. In this study, polymeric and composite coatings with hydroxyapatite obtained under UV light underwent incubation tests in four different artificial biological fluids: simulated body fluid (SBF), artificial saliva, Ringer's fluid, and water (as the reference fluid). The potentiometric and conductometric properties, sorption capacity, and degradation rate of the coatings were examined. Furthermore, their hardness, modulus of elasticity, and deformation were determined. It was demonstrated that the coatings remained stable in SBF liquid at a pH value of around 7.4. In artificial saliva, the greatest degradation of the polymer matrix (ranging between 36.19% and 39.79%) and chipping of hydroxyapatite in the composite coatings were observed. Additionally, the effect of ceramics on sorption capacity was determined, with lower capacity noted with higher HA additions. Moreover, the evaluation of surface morphology supported by elemental microanalysis confirmed the appearance of new apatite layers on the surface as a result of incubation in SBF. Ceramics also influenced mechanical aspects, increasing hardness and modulus of elasticity. For the polymer coatings, the value was 11.48 ± 0.61, while for the composite coating with 15% ceramics, it increased more than eightfold to a value of 93.31 ± 11.18 N/mm2. Based on the conducted studies, the effect of ceramics on the physicochemical as well as mechanical properties of the materials was determined, and their behavior in various biological fluids was evaluated. However, further studies, especially cytotoxicity analyses, are required to determine the potential use of the coatings as biomaterials.

Mechanical behavior and property evaluations of electromagnetic shielding/far infrared functional composite boards made of nano carbon-stainless steel knitted fabrics and far infrared polypropylene

Mechanical behavior and property evaluations of electromagnetic shielding/far infrared functional composite boards made of nano carbon-stainless steel knitted fabrics and far infrared polypropylene

Design of Compact Multiple-test Machine for Evaluation of Electrical and Mechanical Properties of Flexible Thin Electrode

Design of Compact Multiple-test Machine for Evaluation of Electrical and Mechanical Properties of Flexible Thin Electrode

Mechanical Properties Evaluation of 3D Printing Recycled Concrete utilizing Wasted Shell Aggregate

Mechanical Properties Evaluation of 3D Printing Recycled Concrete utilizing Wasted Shell Aggregate

Evaluation of mechanical properties of cement mortars containing pond ash as partial replacement of river sand and prediction of properties by regression models

Despite vast research on the utilisation of coal ashes in cement mortars, many studies lack a comprehensive evaluation of properties related to mortar for masonry and plaster work. This study investigate properties like workability, compressive strength, drying shrinkage, tensile bond strength and adhesive strength through a systematic replacement of river sand by pond ash in cement mortars. Volumetric mix proportions of 1:3, 1:4, 1:5 and 1:6 (cement: sand) were considered, where river sand was replaced in the range of 20–100% by pond ash. At 30% pond ash content, properties like the compressive strength, tensile bond strength and adhesive strength improved in the range of 21–30%, 13–20% and 14–24%, respectively, for all mix proportions. At 60% pond ash content, these strength properties were comparable with those of control mixes and found suitable for mortars for masonry works. However, the drying shrinkage increased with an increase in pond ash content. At 30% pond ash content, drying shrinkage increased in the range of 26–40% for all mix proportions. The thermogravimetric analysis (TGA) showed that mixes with pond ash demonstrated reduced portlandite content compared to the control mixes, resulting in the formation of secondary C-S-H gel. Simple regression models were developed based on experimental results to establish the relationships between different properties. Based on coefficient of determination (R 2), variance inflation factor (VIF) and Durbin–Watson statistics, relationships between the strength and shrinkage properties were very well quantified to be used by researchers and practitioners. Utilisation of pond ash as partial replacement of river sand in mortars proved to be a useful step towards achieving circular economy at the same time reducing threat to depletion of limited natural resources.

Evaluation of mechanical properties, heating rate and radio frequency explosive puffing (RFEP) quality of purple sweet potato under different moisture contents and moisture equilibrium process

The effects of different initial moisture contents (15–55%) and moisture equilibrium process (MEP) on the mechanical properties of the gas-blocking surface layer of purple sweet potato chips and the radio frequency (RF) heating rate, uniformity, and radio frequency explosion puffing (RFEP) quality were discussed in this article. Low-field nuclear magnetic resonance indicated that hot-air pre-drying reduced the amount of free water and caused the transfer of immovable water to bound water. This process was accompanied by an increase in the thickness and elastic modulus of the gas-blocking surface layer, resulting in a significant increase in the RF heating rate and uniformity. Prolonged RF heating time led to a decrease in anthocyanin content. The results demonstrated that the puffing rate initially increased and then decreased with increasing initial moisture content. The puffed sample with an initial moisture content of 45% exhibited the highest puffing rate, crispiness, and porosity. X-ray micro-tomography results reveal that MEP improved the morphology of puffed products, ensuring even distribution of small pores and reducing the presence of hard edges. In conclusion, considering the heating time and anthocyanin retention rate, the initial moisture content ranges from 35% to 45% after MEP was the best pre-treatment.

Study on the rock physical mechanical properties evaluation of tight oil reservoir in Chang 7 member, Longdong area, Ordos Basin, China

The study aims to investigate the rock mechanical properties of the Chang 7 member tight oil reservoir in the Longdong region of the Ordos Basin, China, with the goal of enhancing the efficiency of oilfield development. Despite numerous contributions in the field of rock mechanics, challenges persist in reconciling experimental results with actual geological conditions and achieving comprehensive understanding of rock mechanical properties in tight oil reservoirs. To address this, a variety of experimental methods were employed to systematically assess the mechanical properties of the target reservoir. Rock density was measured using volumetric methods, tensile strength was evaluated through the Brazilian test, uniaxial and triaxial compression tests were conducted to assess rock mechanics properties, and dynamic elastic modulus and Poisson’s ratio were obtained via sonic velocity measurements. Furthermore, differential strain analysis and imaging log analysis were employed to determine the magnitude and direction of geostress. The results revealed that fine-grained sandstone exhibited higher rock density and relatively higher tensile strength, while muddy siltstone exhibited comparatively lower values in these aspects. Analysis of the influence of confining pressure on rock mechanics properties demonstrated a strong positive correlation between compressive strength and Young’s modulus with confining pressure, while Poisson’s ratio exhibited more irregular variations. Additionally, a mathematical relationship between dynamic and static rock mechanical parameters was established. Lastly, based on the characteristics of geostress, reliable foundations for optimizing hydraulic fracturing and wellbore layout were provided. This study has enriched and complemented the investigation of rock mechanical properties in tight reservoirs, offering vital parameters and theoretical support for the development of tight oil reservoirs. This bears significant importance in enhancing petroleum extraction efficiency and optimizing engineering design.

Manufacturing and Evaluation of Mechanical Properties of Aluminum Matrix Composites Reinforced with Continuous Carbon Fibers Using Melting and Casting Process

Manufacturing and Evaluation of Mechanical Properties of Aluminum Matrix Composites Reinforced with Continuous Carbon Fibers Using Melting and Casting Process

Biofilm removal effect of diatom complex on 3D printed denture base resin

For patients who have difficulty in mechanical cleaning of dental appliances, a denture cleaner that can remove biofilm with dense extracellular polymeric substances is needed. The purpose of this study is to evaluate the efficacy of diatom complex with active micro-locomotion for removing biofilms from 3D printed dentures. The diatom complex, which is made by doping MnO2 nanosheets on diatom biosilica, is mixed with H2O2 to generate fine air bubbles continuously. Denture base resin specimens were 3D printed in a roof shape, and Pseudomonas aeruginosa (107 CFU/mL) was cultured on those for biofilm formation. Cleaning solutions of phosphate-buffered saline (negative control, NC), 3% H2O2 with peracetic acid (positive control, PC), denture cleanser tablet (DCT), 3% H2O2 with 2 mg/mL diatom complex M (Melosira, DM), 3% H2O2 with 2 mg/mL diatom complex A (Aulacoseira, DA), and DCT with 2 mg/mL DM were prepared and applied. To assess the efficacy of biofilm removal quantitatively, absorbance after cleaning was measured. To evaluate the stability of long-term use, surface roughness, ΔE, surface micro-hardness, and flexural strength of the 3D printed dentures were measured before and after cleaning. Cytotoxicity was evaluated using Cell Counting Kit-8. All statistical analyses were conducted using SPSS for Windows with one-way ANOVA, followed by Scheffe’s test as a post hoc (p < 0.05). The group treated with 3% H2O2 with DA demonstrated the lowest absorbance value, followed by the groups treated with 3% H2O2 with DM, PC, DCT, DCT + DM, and finally NC. As a result of Scheffe’s test to evaluate the significance of difference between the mean values of each group, statistically significant differences were shown in all groups based on the NC group. The DA and DM groups showed the largest mean difference though there was no significant difference between the two groups. Regarding the evaluation of physical and mechanical properties of the denture base resin, no statistically significant differences were observed before and after cleaning. In the cytotoxicity test, the relative cell count was over 70%, reflecting an absence of cytotoxicity. The diatom complex utilizing active micro-locomotion has effective biofilm removal ability and has a minimal effect in physical and mechanical properties of the substrate with no cytotoxicity.

Optimization and Evaluation of Mechanical and Electrochemical Properties of Ferritic Stainless Steel Welding Using Taguchi Design

The main objective of this work is to optimize welding parameters of AISI 430 FSS welds, focused to minimization of ferrite grains size using Taguchi’s design. Two input parameters of speed and welding current; were chosen to select the minimum grain size and to ascertain their effects on ferrite grain size. ANOVA method was used to evaluate the influence of varying factors on the overall quality of welds. Optimal combination of the parameters were be predicted by S/N analyses, it was accessed on employing an 80 A with 6mm/s. Experimental characterizations of optimum weld joint were performed by using tensile test assisted by image correlations, optical and electronic microscopy. As a result, welding speed had the main influence on grain size by 84.30%. Optimum welding parameter offered finest microstructure with low rate of martensite precipitates in both fusion zone and heat affected zone, and best combination of strength and ductility, it presented a homogeneous distribution of tensile stresses that caused a ductile fracture in base material. ,it is found that that optimized welding parameters permit to give greater resistance to corrosion, which exhibit a lower corrosion current, indicating that coarse ferrite grains are more susceptible to corrosion compared to fine grains.

Microstructure and Mechanical Properties of the EN AC-AlSi12CuNiMg Alloy and AlSi Composite Reinforced with SiC Particles

There is growing interest in developing more advanced materials, as conventional materials are unable to meet the demands of the automotive, aerospace, and military industries. To meet the needs of these sectors, the use of advanced materials with superior properties, such as metal matrix composites, is essential. This paper discusses the evaluation of microstructural and mechanical properties of conventional eutectic EN AC-AlSi12CuNiMg aluminum alloy (AlSi12) and advanced composite based on EN AC-AlSi12CuNiMg alloy matrix with 10 wt% SiC particle reinforcement (AlSi12/10SiCp). The microstructure of these materials was investigated with the help of metallographic techniques, specifically using a light microscope (LM) and a scanning electron microscope (SEM). The results of the microstructural analysis show that the SiC particles are uniformly distributed in the matrix. The results of the mechanical tests indicate that the tensile properties and hardness of the AlSi12/10SiCp composite are significantly higher than those of the unreinforced eutectic alloy. For AlSi12/10SiCp composite, the tensile strength is 21% higher, the yield strength is 16% higher, the modulus of elasticity is 20% higher, and the hardness is 11% higher than unreinforced matrix alloy. However, the unreinforced AlSi12 alloy has a percentage elongation that is 16% higher than the composite material. This shows that the AlSi12/10SiCp composite has a lower ductility than the unreinforced AlSi12 alloy. The tensile specimens of the tested composite broke apart in a brittle manner with no discernible neck development, in contrast to the matrix specimens, which broke apart in a ductile manner with very little discernible neck formation.

Analytical Solution of Ice–Rock-Model Stress Field and Stress Intensity Factors in Inhomogeneous Media

The stress distribution and fracture parameter calibration of ice–rock models are important aspects of studying rock properties at high altitudes and latitudes. However, progress in ice–rock modeling has been slow and singular, and it is limited due to the discrete nature of rocks and the applicability of fracture mechanics. In this study, a circular inhomogeneous ice–rock model is proposed for the first time, and a method is provided for calculating the stress field of the model under biaxial loading. A method for calculating the single-crack stress intensity factor of the model subjected to biaxial compressive loading is also provided. The novelty of this work is that the inhomogeneous ice–rock model is treated as a superposition of two models, namely, a circular pore plate and circular ice, according to the superposition principle. The key is that the stress field distribution law of the ice–rock model is obtained based on the basis of the displacement continuity of the ice–rock interface. The analytical and approximate solutions of the stress intensity factor of a single crack were also obtained by considering the normal phase effect of the crack surface and combining the stress distribution law of the ice–rock model. Comparison with the CAE method was made to verify the correctness of the stress field and stress intensity factor calculation methods. The evolution laws of lateral pressure coefficients, the elastic modulus ratio of ice and rock on the stress field, and the stress intensity factor were analyzed. The effects of lateral pressure coefficients, elastic modulus ratios, and crack distributions on the failure modes were investigated using the extended finite element method (XFEM). This study can provide a theoretical basis for the evaluation of mechanical properties and prediction of the failure modes of frozen rock bodies.

Evaluation of Mechanical Properties with the Use of EPS Polymer for the Preparation of Sustainable Composite Based on Concrete

The civil construction area is one of the activities with the highest consumption of raw materials, presenting a large generation of waste. The use of EPS polymer (expanded polystyrene), in addition to being technological, has a low environmental impact by reducing the use of traditional concrete inputs, in addition to being 100% recyclable, cost-effective. The study enabled the elaboration of the composite based on concrete with different contents of recycled expanded polystyrene (EPS) added (0.20; 0.10 and 0.05%, in % weight/weight). The use of this material allowed the partial replacement of standard sand in the composite aggregate, obtaining an environmentally sustainable material, with low specific mass, thermal resistance with insulating, hydrophobic properties that allow low water absorption, with a low impact manufacturing process. This addition of EPS to the fresh concrete mixture showed a reduction in water penetration, making the construction material more hydrophobic, minimizing infiltration problems, reducing the physical process of absorption. The specimens for the concentration of 0.10% (weight/weight) showed better axial mechanical performance, with an average of 11.4 kgf, 52% in gain of reinforcement effect, in relation to the concentration of 0.20% (weight/weight). For this concentration of 0.20 (weight/weight), the EPS beads obtained greater homogeneity in the dispersion in the cementitious matrix, promoting better impact absorption during mechanical efforts. The absorption test was carried out for 10 and 20 minutes, and with that the percentage of water absorbed for each composite was verified. The specimens prepared with higher contents of styrofoam (0.20% and 0.10%), with 0.98 and 1.29%, respectively, of absorbed water, showed a more hydrophobic character due to the higher percentage of presence of pearls. EPS, making the material less permeable to water. The absorption results were quite satisfactory, showing values ​​below 20%, as recommended in the NBR 8491 standard.

Thermally Conductive and Electrically Insulating Polymer-Based Composites Heat Sinks Fabricated by Fusion Deposition Modeling.

This study explores the potential of novel boron nitride (BN) microplatelet composites with combined thermal conduction and electrical insulation properties. These composites are manufactured through Fusion Deposition Modeling (FDM), and their application for thermal management in electronic devices is demonstrated. The primary focus of this work is, therefore, the investigation of the thermoplastic composite properties to show the 3D printing of lightweight polymeric heat sinks with remarkable thermal performance. By comparing various microfillers, including BN and MgO particles, their effects on material properties and alignment within the polymer matrix during filament fabrication and FDM processing are analyzed. The characterization includes the evaluation of morphology, thermal conductivity, and mechanical and electrical properties. Particularly, a composite with 32 wt% of BN microplatelets shows an in-plane thermal conductivity of 1.97 W m-1 K-1, offering electrical insulation and excellent printability. To assess practical applications, lightweight pin fin heat sinks using these composites are designed and 3D printed. Their thermal performance is evaluated via thermography under different heating conditions. The findings are very promising for an efficient and cost-effective fabrication of thermal devices, which can be obtained through extrusion-based Additive Manufacturing (AM), such as FDM, and exploited as enhanced thermal management solutions in electronic devices.

The effects of copper on the mechanical properties of Ti-10Mo alloy prepared by powder metallurgy method

Titanium alloys are currently widely explored and produced for applications in various engineering fields. Alloying metal elements such as Mo, Cu, and Mn bring more advantages among them to help improve the mechanical properties of titanium alloys. This study is intended for the evaluation of mechanical properties through compression and hardness testing performed on a Ti-10Mo alloy with copper addition by powder metallurgy. Ti-10Mo alloys with the addition of copper contents of 3 wt% Cu, 6 wt% Cu, and 9 wt% Cu were prepared to optimize the properties of Ti-10Mo-xCu alloys. With the addition of 3 wt% copper, the compressive strength increased to 577 MPa, which is the maximum compressive strength in this study. On the other hand, with 6 wt% and 9 wt% Cu addition, the compressive strength became 140 MPa and 201 MPa, respectively. A Ti-10Mo alloy with a 3 wt% copper content was able to achieve the maximum hardness of 576 HV. In short, the addition of 3 wt% copper successfully increased the compressive strength as well as the hardness of the prepared titanium alloys.

Final Irrigant Temoporfin, Femtosecond Laser, and Chitosan Nanoparticles on Extrusion Bond Strength of Glass Fiber Post, Microhardness, and Modulus of Elasticity of Canal Dentin

Final root canal disinfectants Temoporfin, Femtosecond (FS) laser, and Chitosan nanoparticles (NPs) on marten hardness (MH), modulus of elasticity (EIT), and push-out bond strength (PBS) of glass fiber reinforced post (GFRP) to the root dentin. Sixty caries-free single-rooted human premolars were decoronated and a root canal was performed followed by post space. The specimens were then arbitrarily allocated into groups according to the final disinfectant used. Group 1: 17% EDTA, Group 2: Temoporfin, Group 3: FS laser and Group 4: Chitosan NPs. Evaluation of mechanical properties (MH and EIT) was performed on five samples from each group. Ten samples from each group were bonded with GFRP and sectioned. A universal testing machine and stereomicroscope were used to analyze the PBS and failure mode. Means and standard deviations (SD) of MH, EiT, and PBS were assessed using ANOVA and post hoc Tukey. The highest values of MH and EiT were revealed by 5.25% NaOCl+Chitosan NP samples. The lowest scores of MH and EiT were presented by samples irrigated with 5.25% NaOCl+17% EDTA. The coronal section of samples treated with 5.25% NaOCl+Chitosan NPs showed the highest EBS. Chitosan NPs and FS laser have proved to be valuable alternatives to EDTA as both improved PBS without deteriorating the MH and EiT.

Nano-scale characterisation, deformation and failure mechanisms on enhanced-performance modern steels

This research project aims to experimentally study the nature and fundamental characteristics of microstructure, deformation and failure mechanisms, focused on various and complex nanoscale phases, such as precipitations and paraequilibrium phases, not yet completely explained in modern nanophase steels by state-of-the-art literature. Moreover, this work focuses on the investigation of correlation of the microstructure with its impact on the mechanical properties in laboratory-developed novel nanophase steels, which mainly consist of a ductile ferrite matrix, and are strongly affected by appropriate alloy design and thermomechanical treatment differentiations. The microstructural investigation will be accomplished by Light Optical Microscopy (LOM), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM), in conjunction with Energy Dispersive Spectroscopy (EDS) and X-Ray Diffraction (XRD). Mechanical properties evaluation is assessed by hardness tests. The experimental approach has been designed based on the -nano to macro- examination of the materials under investigation to overall understand and explain their nature and properties. Finally, the outcome endeavours to interpret the nanophases’ influence as well as the contribution of alloying elements and thermomechanical and heat treatment routes on the microstructure-properties relationship of these novel nanophase steels.

The effect of reinforcement particles weight percentage on the mechanical properties and plastic flow behaviour of aluminum alloy 7075 matrix material

AbstractIn the present investigation, an aluminum 7075 based hybrid metal matrix composite has been prepared by utilizing the primary reinforcement element (boron carbide with 9 %, 7 %, 5 %, 3 %, and 1 % weight percentage) and secondary reinforcement particles (silicon carbide with 1 %, 3 %, 5 %, 7 %, and 9 % weight percentage) through the well‐known stir‐casting method. Further, the tensile, hardness and Charpy impact tests were performed on the prepared composite material for mechanical properties evaluation. In addition, an attempt has also been performed to analyze the effect of reinforcement weight percentages (primary and secondary) on the strength coefficient, strain hardening rate and strain hardening exponent of the prepared composite material compositions. The results revealed that sample 1 (aluminum 7075/9 weight percentage boron carbide/1 weight percentage silicon carbide) exhibited the maximum 14.12 percent, 14.25 percent and 19.56 percentage increase in hardness, ultimate tensile strength and yield strength respectively than the matrix material. The strain hardening exponent has been increased with the increase in the weight percentage of silicon carbide. Further, the value of the strength coefficient was decreased with the increase in the weight percentage of boron carbide particles. In addition, stage III hardening was associated with the all developed composite material compositions.

Evaluation of Mechanical Properties and Machinability Study of Aluminium Metal Matrix Composite and Mild Steel

Abstract: Machining is one of the Core operations in most of the Manufacturing firms as it consumes most of thetime material and effort. The development of any manufacturing industry lies in a proper controlled machining environment. Hence to avoid wastage of Material and ensure in time production it is necessary to optimize the machining Process. This can be achieved through optimizing certain parameters like Speed, feed, and depth of cut etc. The Controlled machining process can be achieved through Pre simulated study or predicting the values in a computational procedure. Predictive study of parameters ensures better machinability in a specified time without much wastage of resources. In the Present Work turning operation is carried out on A356 Aluminium alloy and Mild steel in a medium duty Lathe with a HSS tool with the cutting parameters of cutting speed of 140, 310, 500m/min, feed rate of 0.35, 0.66, 1mm/rev, and cutting depth 0.5mm. Evaluation of mechanical properties is being carried out to study the influence of reinforcement particles in matrix material and Regression analysis is being carried out to predict the output value with respect to the input value

Evaluation and Comparison of Mechanical Properties of Lithium Disilicate-Based CAD/CAM Blocks

Lithium disilicate are commonly used in dental restoration due to its aesthetic and mechanical performance. However, the patent expiration of the IPS emax system has led to the emergence of other variations of the system. Data and studies concerning mechanical properties of these recent lithium disilicate-based CAD/CAM are scarce and it warrants for an investigation to provide scientific evidence to support its routine use. The aim of this study was to investigate and compare the mechanical properties of lithium disilicate-based CAD/CAM blocks from four different brands. Four CAD/CAM lithium disilicate brands were investigated; IPS emax, Mazic Claro, Cameo, and Tessera. Specimens (n=10) were prepared accordingly; for flexural strength (16 × 4 × 1.2 mm) and microhardness test (15 × 13 × 2 mm). One specimen from each brand was analysed for the microstructure, elemental composition and distribution before and after heat treatment using scanning electron microscope and energy dispersive x-ray spectroscopy. The three-point flexural strength test (n=10) and microhardness test (n=10) was performed. Data were analysed using one-way ANOVA and Dunnett’s T3 test. The results showed that the highest mean flexural strength was from Group 4 Tessera (540.52 ± 143.33 MPa). For microhardness, the highest mean was from Group 1 Mazic Claro (667.70 ± 9.41 HV). Within the four groups, statistically significant difference is noted for flexural strength and microhardness. As a conclusion, Tessera demonstrated significantly higher flexural strength than IPS emax and Cameo. Mazic and Tessera demonstrated significantly higher microhardness than IPS emax and Cameo. All materials tested were above the threshold of 300 MPa.