Average Compressive Strength Research Articles

Deformation and Failure Characteristics of Bimaterial Samples Consisting of Sandstone and Cemented Coal Gangue–Fly Ash Backfill under Uniaxial Loading

Based on the acoustic emission (AE) system and the digital scattered-spot deformation monitoring system, uniaxial compression tests were conducted on composite samples consisting of sandstone and cemented coal gangue–fly ash backfill (CGFB) to investigate their deformation and failure characteristics. The results showed that the average uniaxial compressive strength of the composite samples was 83.09% higher than that of the pure CGFB samples and 92.28% lower than that of the pure sandstone samples. In the composite samples, damage occurred in the CGFB part, and they showed obvious plastic damage characteristics. On both sides of the intersection, the sandstone and the CGFB deformed synergistically in the absence of a macroscopic failure. After a macroscopic failure, the interface effect promoted sandstone deformation and restrained CGFB deformation, transforming the sandstone and the CGFB on both sides of the intersection into a nonsynergistically deformed state. The interface effect had the most obvious influence on the horizontal deformation of the sandstone and CGFB monitoring points near the intersection. The failure of the CGFB samples induced sandstone springback deformation with a springback capacity of 0.0089 mm in the vertical direction and 0.0055 mm in the horizontal direction, which led to the further rupture and failure of the CGFB.

The effect of reinforcement ratio on the flexural performance of alkali-activated fly ash-based geopolymer concrete beam

Alkali activated fly ash (AAFA) based geopolymer concrete structure is getting attention due to its eco-friendly construction characteristics and improved engineering properties. However, comprehensive studies on the structural performance of hardened properties of AAFA geopolymer concrete is not well addressed, especially on non-linear fracture behavior. This paper aims to present the reinforcement ratio effect on the flexural performance and non-linear fracture characteristics of alkali activated fly ash based geopolymer concrete beams. Sixteen finite element (FE) and four experimental models were used to study the effect of reinforcement ratio on the flexural performance and non-linear fracture characteristics. Four groups of concrete specimens with an average compressive strength of 19.30 MPa, 32.60 MPa, 38.2,0 MPa, and 41.70 MPa were utilized under this study. To investigate the effect of reinforcement ratio on flexural performance of the beams, reinforcement ratios of 0.03, 0.042, 0.045, and 0.063 were used for each compressive strength class. The result showed that the ultimate load carrying capacity of the beam showed significant improvement by about 36.38% by increasing of reinforcement ratio from 0.03 to 0.063 by keeping the compressive strength of concrete constant. However, it was observed that the effect of compressive strength was not such substantial as reinforcement ratio in enhancing the ultimate load bearing capacity. The experimental result showed that the increase in ultimate load by keeping the reinforcement ratio constant is about 12.20% for different compressive strength. Furthermore, the crack formation in the concrete was highly associated with the tensile reinforcement ratio, i.e., smaller reinforcement ratio led to higher strain growth in the concrete. Moreover, the validation study between the numerical simulation and test results showed a good agreement.

Coal Ash and Rice Husk Ash Binder for Manufacturing Hollow Blocks

This paper presents the development of a binder from coal ash and rice husk ash for manufacturing hollow blocks. Experiments were conducted to determine the compressive strength of the coal ash and rice husk ash as binders using cylindrical specimens at different curing periods. The mixture proportion with the highest compressive strength in the experiment was adopted in making the 4” hollow blocks. The compressive strength of the hollow blocks with the coal ash and rice husk ash binder was also determined at different curing periods.Cylindrical specimens with four different alkali activators were made and subjected to compression testing on the 3rd, 5th, and 7th day of curing. The mean compressive strength of the cylindrical specimen with all sodium hydroxide activator (RS0CS0) after 7 days curing is 2.54 MPa as compared to 3.05 MPa with the 2.5 sodium silicate to sodium hydroxide ratio (RS1CS0). As the amount of sodium silicate from rice husk was doubled (RS2CS0), the average compressive strength of the 7 days old cylindrical samples increased from 3.05 MPa to 3.49 MPa. Meanwhile, the 7th-day compressive strength of the cylindrical specimen with commercial silica (RS0CS1) was 5.5 Mpa.Hollow blocks were also manufactured based on the material proportion that utilizes RHA with the highest compressive strength or the design mixture RS2CS0. These blocks have a mean compressive strength of 1.22 MPa on the 3rd day, 1.88 MPa on the 7th day, and 2.7 MPa on the 14th day of the curing period.

The Use of Polymer Admixtures for Concrete Quality 45 Mpa Using the Combination of Bangkalan and Pandan Aggregate

Madura Island has natural resource potential, one of which is the result of mining excavations, including class C. Bangkalan Regency has aggregates that could be used in concrete mixtures, including fine aggregate (sand) and coarse aggregate (gravel). The compressive strength of concrete using Bangkalan aggregate, on the other hand, is just 20 MPa, or the regular concrete category. High-quality concrete is one of the most frequently utilized building materials nowadays. Admixture is required to build high-strength concrete, particularly in Bangkalan Regency. In this research, a polymer admixture was used.The goal of this study was to determine the proportion of polymer additives used in the concrete mixture when fine aggregate from Lumajang, coarse aggregate 10/20 from Bangkalan, and coarse aggregate 5/10 from Pandaan were used to achieve a concrete compressive strength of 45 MPa.Based on the findings of research on the usage of polymer-type additives in concrete mixtures using fine aggregate from Lumajang, 10/20 coarse aggregate from Bangkalan, and 5/10 coarse aggregate from Pandaan, a concrete compressive strength of 0.95% Fc '45 Mpa was obtained from cement weight. At the design concrete quality of Fc '45 Mpa, the average compressive strength of concrete aged 28 days is 45.54 Mpa.

Study on damage constitutive relationship of mudstone affected by dynamic pile driving

The mudstone around the pile is damaged during pile driving, altering the mechanical properties of the mudstone. This study conducts standard penetration, uniaxial compression, and triaxial shear tests before and after pile driving. It develops a constitutive damage model of mudstone affected by pile driving based on the statistical damage theory and triaxial test data. The findings in this study show that: (1) The standard penetration number (N) of the clay around the pile remains unchanged after driving because of the thixotropic recovery effect. However, the N of mudstone surrounding the pile decreases by 35.1% on average, (2) The average uniaxial compressive strength is 1.56 MPa before pile driving and 1.12 MPa after pile driving, which decreases by 28.2%. After pile driving, c (cohesion) = 217.2 kPa, φ (internal frictional angle) = 21.6°, (3) The calculated value agrees well with the measured one, verifying the rationality of the model, and (4) The mechanical properties of mudstone change considerably after pile driving, and it is unrealistic to use the mechanical parameters of undisturbed mudstone to design the pile. This research provides theoretical support and parameter preparation for calculating pile driven mudstone foundations.

Modified Paving Block- a Solution for Waste Plastic into Value added Applications for Mathura-Vrindavan City

This investigation is focused on the conversion of waste plastic into modified pavement interlock block (Bitumen: quarry dust: coarse aggregate: rice straw ash: waste plastic:: 5% by weight of aggregate mix : 1:2:2% by weight of aggregate mix : 8% by weight of Bitumen) for Mathura Vrindavan city. The aim of this work is to reduce the rapid accumulation of waste plastic at religious places/ tourist spot by throwing the PET bottles in Mathura Vrindavan city. With the application of these experimental results, can make economical and environment friendly paving block. For each 6.7 no. of paving block, 1 PET bottle (38gm) of 1lit volume consumed hence in 10m2 areas 55.37no. bottles can be utilized. From Marshall Stability- Flow value test, 8% of PET plastic is optimum value which can use in manufacturing of modified paving block with 80/100 grade of bitumen. The average compressive strength of these blocks at 3 and 7 days is15.94MPa and 24.2MPa and the water absorption value is approximately 0.27%. In the presence of sodium sulphate (250gm in 1lit water) loss of weight is around 7.7%. It was estimated that the manufacturing cost of designed paving block is 12Rs. whereas concrete paving block of same size is Rs. 17. Hence its cost quite low as compared to conventional block. Keywords- Mathurav vrindavan city, waste plastic, Bitumen

Hydroxyapatite Humidifier Vibrator Housing Fabrication and Characteristics

The humidifier vibrator housing is difficult to clean and prone to contamination due to its metallic material. To overcome these shortcomings, the humidifier vibrator housing was manufactured using Hydroxyapatite as a raw material. Although hydroxyapatite has excellent antibacterial properties and biocompatibility, it is difficult to manufacture a sintered body due to its weak fracture toughness. Therefore, hydroxyapatite sintered compacts were prepared according to the amount of plasticizer added and their physical properties were compared. The average compressive strength was 395.1 N·mm-2 at 8 % of the amount of added plasticizer, and the average bending strength was 61.8 N·mm-2 at 6 % of the amount of added plasticizer. The hydroxyapatite sintered compact showed the effect of inhibiting the production of bacteria regardless of the amount of plasticizer added. As a result of this physical property study, it was possible to develop a humidifier vibrator housing with excellent antibacterial properties and maintaining mechanical strength.

Preparation and properties of highly loaded SnO2-based porous electrodes by DLP 3D printing

In this study, highly loaded tin oxide-based (SnO2-based) porous electrodes were prepared by digital light processing (DLP) 3D printing technology. Firstly, the SnO2 light-cured slurry was prepared. The curing process and heat treatment process were analyzed and optimized. Then the best process parameters were obtained. Antimony oxide (Sb2O3) was selected as the conductive agent to improve the electrical conductivity of the SnO2-based electrode. Through the characterization of resistivity, SEM and XRD, the optimum doping amount of conductive agent Sb2O3 was determined to be 6 wt. %. Three kinds of porous electrodes with different shapes were prepared by DLP 3D printing, and the printing accuracy and mechanical properties were characterized. The results showed that the forming dimension error was about 1.7 % in the X and Y direction, 2.3 % in the Z direction. And the average compressive strength was 18.1 MPa, which effectively ensured the shape integrity and mechanical stability of the printed parts. Then the electrochemical properties of DLP 3D printed SnO2-based electrode and conventional coated electrode were tested and compared. The results showed that the 3D printed porous electrode showed lower charge transfer impedance and higher ion diffusion efficiency, and the maximum charge transfer impedance could be reduced to 1/25 of the traditional electrode; At the same time, it showed better cycle performance and rate performance, and the capacity retention of the 3D printed porous electrode could be improved by about 29.0 % compared with the traditional electrode. This work shows that high-performance high-load porous electrodes can be accurately prepared by DLP 3D printing, which provides a new strategy for the future development of high-load thick electrodes.

Effects of Hydration during Drilling on Fracability of Shale Oil Formations: A Case Study of Da’anzhai Section Reservoir in Sichuan Basin, China

Accurate evaluation of shale oil reservoir fracability helps avoid blind fracturing and ensures efficient fracturing. However, the current evaluation of the fracability index rarely considers the impact of hydration caused by drilling fluid invasion during drilling. The results of a rock triaxial mechanical test conducted to evaluate the mechanical properties of shale oil reservoirs are reported in this paper. Based on the results, we developed a comprehensive evaluation method of shale oil reservoir fracability that considers hydration; the effects of the brittleness index, horizontal difference stress, and fracture toughness; and the law of water phase intrusion into shale oil reservoirs. The research results show that the average compressive strength decreased by 37.99%, the average elastic modulus decreased by 53.36%, and the average Poisson’s ratio increased by 68.75% after being soaked for 48.00 h at 80 °C and 30.00 MPa. The water saturation rate at the borehole wall was the highest; with the extension to the stratum, it gradually decreases to the original water saturation rate of the formation, while the fluctuation radius gradually increases with time. The Young’s modulus and fracture toughness decrease, the Poisson’s ratio increases, and the fracability index reaches a maximum value at the wellbore (i.e., the highest water saturation rate), indicating that the strength of the hydrated rock decreases and it can be easily fractured. The case analysis shows that the optimal fracturing position of the Da’anzhai Section of Well NC2H is around 2600 m deep. After the hydration occurs, the fracture initiation pressure of the formation is reduced from the original value of 72.31 MPa to 66.80 MPa. This indicates that when hydration decreases, the formation fracture pressure also increases. The research presented in this paper can be used to optimize fracture location and set a reasonable fracturing pressure.

Self-Healing Bio-Concrete Using Bacillus subtilis Encapsulated in Iron Oxide Nanoparticles.

For the creation of healable cement concrete matrix, microbial self-healing solutions are significantly more creative and potentially successful. The current study investigates whether gram-positive "Bacillus subtilis" (B. subtilis) microorganisms can effectively repair structural and non-structural cracks caused at the nano- and microscale. By creating an effective immobilization strategy in a coherent manner, the primary challenge regarding the viability of such microbes in a concrete mixture atmosphere has been successfully fulfilled. The iron oxide nanoparticles were synthesized. The examined immobilizing medium was the iron oxide nanoparticles, confirmed using different techniques (XRD, SEM, EDX, TGA, and FTIR). By measuring the average compressive strength of the samples (ASTM C109) and evaluating healing, the impact of triggered B. subtilis bacteria immobilized on iron oxide nanoparticles was examined. The compressive strength recovery of cracked samples following a therapeutic interval of 28 days served as a mechanical indicator of the healing process. In order to accurately correlate the recovery performance as a measure of crack healing duration, the pre-cracking load was set at 80% of the ultimate compressive stress, or "f c," and the period of crack healing was maintained at 28 days. According to the findings, B. subtilis bacteria greatly enhanced the compressive strength and speed up the healing process in cracked cement concrete mixture. The iron oxide nanoparticles were proven to be the best immobilizer for keeping B. subtilis germs alive until the formation of fractures. The bacterial activity-driven calcite deposition in the generated nano-/micro-cracks was supported by micrographic and chemical investigations (XRD, FTIR, SEM, and EDX).

Irregular Shape Effect of Brass and Copper Filler on the Properties of Metal Epoxy Composite (MEC) for Rapid Tooling Application

Due to their low shrinkage and easy moldability, metal epoxy composites (MEC) are recognized as an alternative material that can be applied as hybrid mold inserts manufactured with rapid tooling (RT) technologies. Although many studies have been conducted on MEC or reinforced composite, research on the material properties, especially on thermal conductivity and compressive strength, that contribute to the overall mold insert performance and molded part quality are still lacking. The purpose of this research is to investigate the effect of the cooling efficiency using MEC materials. Thus, this research aims to appraise a new formulation of MEC materials as mold inserts by further improving the mold insert performance. The effects of the thermal, physical, and mechanical properties of MEC mold inserts were examined using particles of brass (EB), copper (EC), and a combination of brass + copper (EBC) in irregular shapes. These particles were weighed at percentages ranging from 10% to 60% when mixed with epoxy resin to produce specimens according to related ASTM standards. A microstructure analysis was made using a scanning electron microscope (SEM) to investigate brass and copper particle distribution. When filler composition was increased from 10% to 60%, the values of density (g/cm3), hardness (Hv), and thermal conductivity (W/mK) showed a linear upward trend, with the highest value occurring at the highest filler composition percentage. The addition of filler composition increased the compressive strength, with the highest average compressive strength value occurring between 20% and 30% filler composition. Compressive strength indicated a nonlinear uptrend and decreased with increasing composition by more than 30%. The maximum value of compressive strength for EB, EC, and EBC was within the range of 90–104 MPa, with EB having the highest value (104 MPa). The ANSYS simulation software was used to conduct a transient thermal analysis in order to evaluate the cooling performance of the mold inserts. EC outperformed the EB and EBC in terms of cooling efficiency based on the results of thermal transient analysis at high compressive strength and high thermal conductivity conditions.

Utilization of flue gas desulfurization gypsum waste as a partial substitution of cement for the production of concrete bricks

This research aims to determine the use of flue gas desulfurization gypsum waste as a partial substitution of cement for the manufacture of concrete bricks. Flue gas desulfurization gypsum is waste from the tin processing that takes place. This research uses flue gas desulfurization gypsum waste compositions of 5%, 15%, 25%, and 35% by weight of cement. The design of the concrete brick was mixed with a design compressive strength value of 5 MPa and is included in the class II quality category according to SNI 03-0349-1989 concerning concrete bricks for masonry walls with a water-cement factor value of 0,4. The size of the test object is 40 x 10 x 20 cm, where the making of concrete brick uses a hydraulic press machine with a total sample of 40 pieces. The results showed that the use of flue gas desulfurization gypsum could increase the compressive strength with a substitution percentage of 5% with an optimum average compressive strength value of 8,569 MPa and the optimum water absorption value with a 5% substitution percentage of 9,315%. The percentage above 5% experienced a decrease in the average compressive strength and an increase in the average water absorption capacity of the concrete bricks.

ANALISIS KUAT TEKAN BETON MENGGUNAKAN LIMBAH BOTOL KACA SEBAGAI PENGGANTI SENAGIAN AGREGAT HALUS DAN GULA MERAH SEBAGAI BAHAN TAMBAH / ADITIF BETON

Various studies in the field of concrete were carried out in an effort to improve the quality of concrete, thetechnology of the research and experiment materials intended to answer the increasingly high demands on the useof concrete.One way to reduce excessive mining of natural materials is by utilizing waste glass bottles and brown sugar,especially glass bottles which area lot of waste and accumulate in the environment around the house.This study aims to analyze the compressive strength of concrete using wasteglass bottles and brown sugar as a substitute for fine aggregate and water. Mix Design in glass bottles and brownsugar as a substitute for fine aggregate and water. Mix Design in This study uses the SNI 2000 method. Thecomposition of glass bottle waste is 5% and 10% to fine aggregate while brown sugar is 0.25% and 0.50% againstwater. The specimens were cylindrical in shape with a diameter of 15 cm and a height of 30 cm as many as 24specimens aged 7, 14 and 28 days. The results of the average compressive strength using glass bottle waste and brown sugar with a composition of 5% and 10% for fine aggregate and 0.25% and 0.50% for water, namely for variation 1 of 8.98Mpa, 11.74 Mpa , 16.06 Mpa while for variation 2 it is 7.45 Mpa, 9.87 Mpa, 14.99 Mpa. then the percentagereduction of concrete variations 1 and 2 against normal concrete is 4.02%, 5.86%, 3.94% and 5.55%, 7.73%,5.01%.

EFFECT OF ADDING SUPERPLASTICIZER ON HIGH INITIAL COMPRESSIVE STRENGTH OF HIGH-PERFORMANCE CONCRETE (HPC) FC’= 36.62 MPA

This research aims to determine the effect of the most optimal variation of the addition of Sikament- NN in producing high initial strength in High Performance Concrete (HPC) using Superplasticizer (Sikament-NN) added material on the compressive strength of concrete Fc' = 36.62 Mpa or K-450, by using 4%,5%,6%,7% and 8% variation of the Superplasticizer Sikament NN with the effect of accelerating hardening and strengthening the concrete to determine the most optimal variation. Researchers will test 150 cylindrical-shaped concrete samples with a size of 15 x 30 cm at the age of 3, 7, 14, 21 and 28 days. The result shows that the most optimum high initial compressive strength was achieved by concrete with 5% Sikamen NN added, at the age of 3 days with the initial compressive strength of the test object has surpassed the design compressive strength by 100.4% or equal to 34.65 Mpa, while at the age of 28 days produces an average concrete compressive strength of Fc' = 57.77 Mpa.

Influence of Mesoscopic Parameters of Weakly Cemented Rocks on Macroscopic Mechanical Properties

In weakly cemented rocks, the mesoscopic parameters have a great influence on the macroscopic mechanical properties. One example of a typical weakly cemented rock is the Cretaceous coarse sandstone in the Hongqinghe Coal Mine. In this study, rock samples were subjected to physical and mechanical experiments, from which a sample model was constructed based on particle flow theory. Uniaxial compression numerical simulation experiments and analyses were conducted, and sensitivity analyses of various microscopic parameters in relation to the macroscopic mechanical properties of the rock were performed via a control variable method. A response mechanism between the macroscopic and mesoscopic parameters was then inferred. On the microscopic scale, the rock is porous with a loose structure and extremely low average uniaxial compressive strength, indicating looseness and weakness. The mesoscopic parameters were then divided into three grades based on their degrees of influence from high to low on the peak strength, peak strain, and elastic modulus. Laboratory experiments revealed that the fracture form of weakly cemented coarse sandstone is typically due to single-section shear failure, whereas through simulation, cracks are caused mainly by tension failure. These two failure modes were inferred to be consistent with each other.

Development of clayey ceramic membranes prepared with bio-based additives: Application in water and textile wastewater treatment

Eco-friendly ceramic membranes have been developed from clayey materials mixed with biobased additives (woodworking waste and rice husk) as pore-forming agents. Heated blends of two clayey occurring materials with the biobased additives (up to 20 wt%) were investigated using X-Ray Fluorescence spectrometry (XRF), X-Ray Diffraction (XRD), Thermogravimetric Analysis (TDA-TG), Mercury Porosimetry, Scanning Electron Microscopy/Energy Dispersive Spectroscopy (SEM-EDS) and Filtration tests. The effect of adding the pore-forming agent on the physical and mechanical properties (apparent density, apparent porosity, average pore diameter and compressive Strength) was assessed and the results were interrelated to the microstructural changes. The mineralogical analyzes showed that original minerals together with thermal decomposition products were involved in the neoformation process. SEM observations displayed the appearance of several pores with various shapes, sizes and features corresponding to the neoformed phases (gehlenite and albite) and localized heterogeneous aspects. The experimental filtration tests have clearly shown the elimination of turbidity and suspended matter with the reduction of the chemical/biological oxygen demand and the dye concentration. Thereby, it was confirmed that ceramic membranes intended for filtration with homogenous morphological aspect, good physical properties and high mechanical strength could be manufactured and used in industrial wastewater treatments.

Investigation of the Effect of Weathering of Selected Charnockite Rocks in Nigeria on Its Engineering Properties

The effect of alteration in the petrographic characteristics of charnockite on its strength, its engineering properties and transformations of the specific gravity which took place during weathering has been examined in this study. This study characterized selected samples of un-weathered and weathered charnockite rocks of Ijare, Ondo State, Nigeria. The physical properties determined were specific gravity, density, porosity, water content and water absorption while the mechanical properties investigated include the point load strength index. Results from the analysis carried out reveal: the point load index of 5.74Mpa and 3.72Mpa for unweathered and weathered samples; average uniaxial compressive strength of 136.90Mpa and 65.50Mpa for unweathered and weathered samples; slake durability of 98.80% and 97.80% for unweathered and weathered sample; Schmidt rebound value of 49Mpa and 45Mpa for both the unweathered and weathered samples respectively. The rock samples were also subjected to petrographical analysis whose result shows that weathering increases some investigated physical properties like porosity, water content and water absorption of the rock while decreasing the specific gravity and density. The result of the tests shows the bulk and dry densities increase for both the weathered and unweathered samples; increased degree of weathering equally results in a major reduction in the strength of the charnockite rock which is directly associated with changes in mineralogy and associated porosity. The point load strength, uniaxial compressive strength test and rebound hardness result values decreases because of weathering. Weathering processes also affected the physical properties of rock, mineralogy, chemical composition as well as the mechanical properties of the rock thereby reducing the strength and mechanical behavior of the rock materials.

A field study on the behaviour of driven and drilled micropiles implemented in clay

Micropiles are often implemented through drilling, steel pipe installation, reinforcement and grouting. However, in some parts of the world, especially in areas with fine-grained soils, these shafts are implemented by steel pile driving, followed by reinforcement, and grouting has been expanded considerably. In this study, micropile shafts were installed at the site by both driving and drilling methods. Reinforcement and grouting were carried out by two-step grouting and applying different grouting pressures in the micropiles. Some boreholes (at a distance of 0.3 m from the micropile axis) and test pits were drilled to investigate the penetration radius of the grout at different grouting pressures. Results showed that the bearing capacity of driven micropiles is about 4 to 14% more than that of drilled micropiles due to the soil compaction impacts. The average uniaxial compressive strength of the soil samples after micropiles grouting was dependent on the applied grouting pressure and increased from 25 to 56%. In addition, the direct shear test results showed an increase of 15% in the soil cohesion and an increase of 4° in the internal friction angle for the soil after grouting of the micropiles.

Investigating the effects of Silicone Rubber (SR), Polyether Ether Ketone (PEEK), and Nanoclay on the mechanical properties of artificial granite stone

ABSTRACT This study aimed to investigate the effect of Silicone Rubber (SR), Polyether Ether Ketone (PEEK), and Nanoclay on the mechanical properties of granite artificial/engineered stone. In this study, two types of resins called epoxy resin and vinyl ester resin as an adhesive and also three types of additives called SR, PEEK, and Nanoclay as properties modifiers are used. Waste granite aggregate has also been used to fabricate all the specimens. Specimens modified with PEEK had an average compressive strength of about 40% and 132% more than the control specimens in specimens made with epoxy resin and vinyl ester resin, respectively. Also, the flexural strength results of the fabricated specimens showed that adding SR to the vinyl ester resin is the best option to obtain the highest flexural strength. Analysing the tensile strength results of the specimens made with three types of additives, the results showed that adding SR to the specimens made with epoxy resin is the best option to obtain the highest tensile strength for them. It can be concluded that the suitable additive to increase the tensile and flexural strength of the specimens is SR, which increases these strengths by 20.7% to 46.2% and 7.2% to 18.2%, respectively.

Wire and arc additive manufactured an innovative material Ti-Al-V-Ni-Cr-Mo-Nb-Cu alloy: Study of its microstructure and mechanical properties

In this study, Ti-Al-V-Ni-Cr-Mo-Nb-Cu alloy was successfully fabricated in-situ for the first time by ternary-wire + arc additive manufacturing (WAAM) technology using Ti6Al4V, Inconel625 and pure Cu wires. The microstructure and mechanical properties were investigated accordingly. The results show that the phase consisted of NiTi (B2), NiTi (B19′), TiCu and Ti2Cu phases. The microstructure was mainly composed of gray matrix Ti(Ni, Cu) and black second phase precipitation Ti2(Ni, Cu). The average compressive strength of the sample was 1211.98 MPa and the average compressive strain was 4.95 %. In the designed composition, the average microhardness was 677 HV0.2.