Ultimate Tensile Research Articles

Metallurgical Behaviour and Characterization on Polymer Metal with HCHCr Tool by using Friction Stir Welding Adopting L27 Taguchi Technique

Friction stir welding is a technique of combining harmless for the environment because it doesn’t use flux or any other shield gas and doesn’t produce hazardous gas. To study the FSW process on composite material this work offers an experimental enquiry and optimisation technique. In this investigated how input process operating factors like tool rotational speed, feed rate and depth of cut affect an output parameter like hardness of welded connections and Ultimate Tensile Strength (UTS), Microstructure and metallurgical on the metal. To achieve this L27 Taguchi approach orthogonal array used to optimise design tests on friction stir welding parameters and also HCHCr tool used to improve the good weld ability and to increase the heat input. The experimental setup is run with several combinations of process parameters such as 900, 1000, and 1200 rpm of Tool rotational speed 20 mm, 25 and 30 mm as feed rate by adjusting the depth of cut values of 5.4 mm, 5.6 mm and 5.8 mm respectively. Additionally, utilising the regression analysis equations (ANOVA) used to identify the significant input parameters how it effects for the output metal structure. Finally, by achieved effective evaluation of the metallurgical and microstructure on the nylon 6A metal by various analysis and Testing.

Machine learning-assisted pattern recognition algorithms for estimating ultimate tensile strength in fused deposition modelled polylactic acid specimens

ABSTRACT In this study, we investigate the application of supervised machine learning algorithms for estimating the Ultimate Tensile Strength (UTS) of Polylactic Acid (PLA) specimens fabricated using the Fused Deposition Modeling (FDM) process. 31 PLA specimens were prepared, with Infill Percentage, Layer Height, Print Speed, and Extrusion Temperature serving as input parameters. The primary objective was to assess the accuracy and effectiveness of four distinct supervised classification algorithms, namely Logistic Classification, Gradient Boosting Classification, Decision Tree, and K-Nearest Neighbor, in predicting the UTS of the specimens. The results revealed that while the Decision Tree and K-Nearest Neighbor algorithms achieved an F1 score of 0.71, the KNN algorithm exhibited a higher Area Under the Curve (AUC) score of 0.79, outperforming the other algorithms. The findings offer valuable insights into the potential use of machine learning techniques in improving the performance and accuracy of predictive models in additive manufacturing.

The Challenge of Impurities (Fe, Si) to Recycling in the Rolled Aluminum Industry in the Coming Years in Relation to Their Influence on Ultimate Tensile Strength

The increased recycling in aluminum production has raised the impurity content in the industry, thus increasing its effect on mechanical characteristics and making it difficult for recycled products to meet the properties’ goals as their effect is not yet sufficiently known. Therefore, the two main impurities (Fe and Si) in standard aluminum rolling mill products of alloy 5754 were investigated to determine their effects on the ultimate tensile strength (UTS). After analyzing the composition, mechanical properties, and microstructure, the relationship of both impurities with the UTS in fully annealed products was estimated by statistical analysis, obtaining a strong influence of Si and Fe.

Effect of Fiber Sizing Levels on the Mechanical Properties of Carbon Fiber-Reinforced Thermoset Composites.

Fiber sizing is one of the most important components in manufacturing composites by affecting mechanical properties, including strength and stiffness. The sizing of manmade fibers offers many advantages, such as improving fiber/matrix adhesion and bonding properties, protecting fiber surfaces from damage during the processing and weaving stages, and enhancing the surface wettability of polymer matrices. In this work, the influence of fiber sizing levels on carbon fibers' (CFs) mechanical properties is reported at room temperature using single fiber tensile testing (Favimat+), single fiber pullout testing (SFPO), and interfacial elemental analysis by X-ray photoelectron spectroscopy (XPS). Standard modulus CFs (7 ± 0.2 μm in diameter) were sized using two commercially available Michelman sizing formulations. The average solid content for each sizing formulation was 26.3 ± 0.2% and 34.1 ± 0.2%, respectively. HEXION RIMR 135 with curing agent RIMH 137 was used as a model thermoset epoxy matrix during SFPO measurements. A predictive engineering fiber sizing methodology was also developed. Sizing amounts of 0.5, 1, and 2 wt.% on the fiber surface were achieved for both sizing formulations. For each fiber size level, 50 single-fiber tensile testing experiments and 20 single-fiber pull-out tests were conducted. The ultimate tensile strength (σult) of the carbon fibers and the interfacial shear strength (τapp) of the single fiber composite were analyzed. The sizing levels' effect on interfacial shear stress and the O/C (Oxygen/Carbon) surface composition ratio was investigated. Based on our experimental findings, an increase of 6% in fiber performance was recorded for ultimate tensile and interfacial shear strengths. As a result, generalized fiber sizing and characterization methods were established. These developed methods can be used to characterize the strength and interfacial shear strength of manmade fibers with different sizing formulations and solid contents irrespective of the matrix, i.e., thermoset or thermoplastic.

Submerged Arc Welding of SA 516 Gr70 Material: Parametric Optimization of Mechanical Properties UT-Strength and Hardness

In this study, the Taguchi technique was employed to optimize the process parameters of submerged arc welding (SAW) in terms of mechanical properties such as Ultimate Tensile Strength (UTS) and hardness. The study considered a variety of weld quality factors and provided a detailed explanation of the procedure and results using the Taguchi method, which is a statistical analysis approach that requires fewer trials. The experiment was conducted on SA 516 GR70 material using a L9 orthogonal array and a range of current, voltage, and speed settings. The comparison of anticipated and experimental values with the mathematical model of regression analysis-ANOVA with and without interaction helped in achieving the desired results. Lastly, a verification experiment confirmed that the Taguchi technique is reliable in predicting UTS and hardness performance. Overall, this research provides valuable insights into optimizing the SAW process parameters for mechanical properties and demonstrates the effectiveness of the Taguchi technique in predicting and achieving optimal welding performance.

Enhanced strength ductility and wear resistance in a friction stir processing engineered AZ31B/TiC magnesium-based nanocomposites

ABSTRACTIn the present investigation, efforts have been made to fabricate a magnesium-based AZ31B nanocomposite by integrating nano-sized titanium carbide (TiC) particles via utilising the friction stir processing (FSP) process. The primary objective of the research was to enhance the metallurgical, mechanical, and tribological properties of the base material while investigating the influence of secondary phase particles and various FSP parameters. The findings were rigorously validated through a comprehensive analysis, which encompassed the use of various testing apparatus, such as optical microscopy, field emission scanning microscopy, microhardness testers, tensile and compressive testing machines, along with fractography analysis for wear morphology and tensile properties. The results indicate that the nanocomposite produced under the conditions of a tool rotation speed of 1600 rpm and a transverse speed of 40 mm/min along with three number of FSP passes exhibits superior mechanical and tribological properties compared to both other developed composites and the base alloy. A significant enhancement of nearly 2.68 times in microhardness values along with simultaneous refinement in grain size up to 14.85 times was obtained. Ultimate tensile and compressive strengths report an impressive increase in values up to 2.16 and 1.6 times respectively when compared to the base metal. Furthermore, the tensile fracture behaviour of the base magnesium alloy indicated brittleness, while the AZ31B/TiC composite displayed a combination of ductile and brittle features. In terms of wear morphology, the base magnesium alloy exhibited adhesive and abrasive wear, while the composite demonstrated particle pull-out, delamination, and localised plastic deformation, with enhanced resistance to wear. These findings underscore the significant improvements achieved in mechanical and tribological properties, thus emphasising the novel contributions of this research to the field.

Investigation of mechanical characteristics of coir fibre/hexagonal boron nitride reinforced polymer composite

Coir fibre, derived from the husk of coconuts, is a natural resource and they are biodegradable and renewable. By incorporating them, any product can become more lightweight and durable, meeting the global desire for eco-friendly and efficient designs. This study has the potential to significantly alter the design of components such as switches and enclosures and it has an international research impact on engineering applications. Coir fibres and Hexagonal-Boron Nitride (h-BN) possess superior mechanical, thermal and physical qualities when reinforced with polymers. Hence novel study is carried out to examinecoir fibre/h-BN reinforcement in epoxy polymer composites. Response Surface Methodology via Box-Behnken Design (BBD) is utilized to investigate the mechanical properties such as Tensile Strength, Impact Strength and Young’s Modulus of coir fibre/h-BN reinforced epoxy polymer composite. The effect of input parameters onresponse is evaluated through regression equation and analysis of variance by using statistical Minitab software. The response optimization represents the maximum Young’s modulus (1597 MPa) by combining coir fibre (5 wt%), Coir fibre powder size (75 μm) and h-BN (1 wt%). The response optimization portrays the maximum Ultimate Tensile strength(36.83 MPa) by combining coir fibre (1 wt%), coir fibre powder size (220 μm) and h-BN (3.78 wt%). The response optimization reveals the maximum Impact strength (98.35 J m−2) by combining coir fibre (5 wt%), coir fibre powder size (225 μm) and h-BN(1 wt%). This work emphasises the use of composite materials that are environmental friendly in a variety of industries such as automotive, electrical, etc.

Carboxymethyl Cellulose-Amuniacum Gum Based Edible Films Enriched with Clove Essential Oil: Optimization Formulation Using Response Surface Methodology (RSM)

Backgraound: Polysaccharides, particularly Carboxymethyl Cellulose (CMC) and Ammoniacum Gum (AMG), are considered valuable due to their thermal stability and non-toxicity. CMC has good film-forming ability but weak mechanical properties, while AMG shows promise with its unique chemical composition. Additionally, essential oils, such as Clove Essential Oil (CEO), are being used to enhance the antimicrobial properties of edible films, offering a natural way to extend the shelf life of food products.
 Methods: This study investigated the combined effect of CMC: 0.5-1.5 wt %, AMG: 1-5 wt %, as well as CEO: 0-30 v/v % on the physical characteristics of the CMC-AMG films by Response Surface Methodology. The optimization was performed with the aim of maximizing Whiteness Index, Ultimate Tensile Strength (UTS), and Strain at Break (SB) and minimizing total color difference (ΔE) values. Fourier-Transform Infrared Spectroscopy, film microstructure, Differential Scanning Calorimeter analysis, and antibacterial activity were investigated. The analysis was conducted using Design Expert software version 10.00 (STAT-EASE Inc., Minneapolis, USA).
 Result: The films with the highest UTS have been obtained through a composition of 5 g CMC, 1.5 g AMG, and 15% CEO. On the contrary, using a composition of 5 g CMC, 1 g AMG, and 30% CEO revealed the highest SB (115.41%). The highest UTS value of 13.17 MPa was obtained with a formulation consisting of 5% AMG, 1.5% CMC, and 15% CEO. Nevertheless, the maximum SB value of 115.41% was achieved with a formulation containing 5% AMG, 1% CMC, and 30% CEO. Moreover, heterogeneous microstructure and more opaque films were obtained as identified by the higher ΔE. The Differential Scanning Calorimeter results demonstrated that incorporating a CEO did not impinge on thermal stability. Furthermore, the addition of CEO led to a rise in antimicrobial activity against Salmonella enterica, Pseudomonas fluorescens, Escherichia coli, and Listeria monocytogenes.
 Conclusion: In conclusion, combination of CMC and AMG in optimum levels, led to the production of a film with acceptable mechanical properties. Also, these films showed significant antimicrobial activity.

High Temperature Tensile Properties and Microstructure of Ni20Cr Alloy Fabricated by Laser Powder Bed Fusion

Additive Manufacturing (AM) brings about an array of modifications in microstructure with respect to conventional routes transforming mechanical performances. These new microstructure features depend on process parameters and especially on volume energy-density delivered by the laser on powder layer. Among the different alloys manufactured by AM, Ni-alloys exhibit high-strength at elevated temperature opening the way of fabrication of gas turbines and jet-engine parts. Ni-superalloys experience precipitation hardening due to the formation of γ′ and γ′′ phases leading to complex microstructures. To better study the influence of the AM microstructure on Ni-alloys mechanical properties, in particular at elevated temperatures, a theoretically monophasic and binary Ni20Cr-alloy manufactured by laser powder-bed fusion was studied in this work. Remarkable Yield Strength (400 MPa) and Ultimate Tensile Strength (UTS) (600 MPa) were observed at 500°C with hardly any loss of properties from room temperature, owing to the thermal stability of cellular dendrites till 700°C. Ductility drop was reported at 700°C due to anomalous brittle behaviour of Ni-alloys. Hardening behaviour vanished at 900°C signifying the deletion of dendrites, disappearance of dislocations, diffusion of Cr from dendritic walls and growth of oxides.

The nanocrystalline and high density dislocation-Enabled ultrahigh strength and ductility of Al0.4Co0.5V0.2FeNi high entropy alloy

The evolution of the microstructure and mechanical properties of a vacuum arc melted non-equiatomic Al0.4Co0.5V0.2FeNi high-entropy alloy (HEA) subjected to severe plastic deformation was investigated experimentally and by simulations. The present work explored duplex HEAs, comprising a face-centered cubic (FCC) matrix and a body-centered cubic (BCC) phase, towards outstanding their mechanical responses. The Al0.4Co0.5V0.2FeNi alloys had a duplex structure, i.e., with dispersed B2-phase islands (with sizes of dozens of microns) in several hundred micron-, even millimeter-sized FCC grains. The mechanical properties of this HEA were strongly deformation dependent, i.e., when deformation increased from 30 % up to 60 %, the yield strength and ultimate strength tensile increased from ∼0.9 GPa and 1.0 GPa to ∼1.2 GPa and 1.3 GPa, respectively. During tensile deformation, initial fractures occurred in the FCC phase located close to the interface between the FCC and BCC phases. With an increase of deformation, the fracture degree in the FCC phase got larger, and fractures also appeared in the BCC phase. Combined with the geometric dislocation density calculation results from an electron backscatter diffraction (EBSD) analysis, it can be seen that the dislocation density near the phase interface of FCC was higher, making it more likely to produce defects.

Effects of thermal ageing time and temperature during heat-treatment on the mechanical properties of fiber laser welded Nb-1%Zr-0.1%C alloy in continuous wave mode

The effects of thermal ageing time and temperature used during heat-treatment were studied on tensile strength, elongation, and microhardness of the laser welded Nb-1%Zr-0.1%C alloy in continuous wave mode. Post-weld heat treatment (PWHT) was carried out by varying the temperature and time in the ranges of (850–1050) °C (that is, about the recrystallisation temperature) and (0.5–4) h (as the weld samples were prepared in the form of sheets), respectively. The grain sizes of fusion zone (FZ), and FZ heat treated at 850 °C for 4 h and that at 950 °C for 2 h were found to be equal to 52.85 μm, 84.89 μm and 116.43 μm, respectively. The segregation of zirconium, carbon and oxygen increased grain boundary energy and induced brittleness to the grain boundary, resulting in loss of ductility. The micro-hardness and Young's modulus values were observed to increase in the FZ compared to that of the base metal (BM), but their decreasing trends were noticed during the heat-treatment due to the grains' softening. For the PWHT samples, the plasticity was found to decrease to about 57% of that of BM. This was attributed to the precipitation of carbides, grain growth, and dislocation pinning during the ageing process. During the heat-treatment of the welded samples, both Yield Strength (YS) and Ultimate Tensile Strength (UTS) were found to decrease to 77% and 86%, respectively, of that of the BM.

Effect of microstructural evolution during melt pool formation on nano-mechanical properties in LPBF based SS316L parts

Laser Powder Bed Fusion (LPBF) based SS316L parts have a wide range of industrial applications, mainly due to their high strength and good structural integrity. However, there is a lack of nano-mechanical studies related to microstructural evolution. The SS316L cubes were examined for grain orientation and phase transformation with the help of OM and FESEM with EDX analysis. Cellular and columnar grains were substantiated by FESEM with EDX. Further, the δ ferrite and γ austenite phases occurrence was evident in XRD analysis. The orientation of grains was further examined through EBSD analysis. The microstructural transformation was substantiated by mapping based on modulus. Cellular grains showed a maximum hardness of 6 Gpa, whereas the transverse columnar grains displayed a minimum elastic modulus of 105.8 GPa. Nano-wear and scratch analysis predicted the functions caused by the occurrence of cellular dendritic microstructure, and the topographic wear and scratch tracks confirmed the soft nature of transverse columnar grains by forming more pile-up of materials. Strain Rate Sensitivity (SRS) of the SS316L specimens was analysed based on three different strain rates (4.1 ×10−5 s−1, 2.08 ×10−4 s−1 and 3.3 ×10−4 s−1). It was concluded that the LPBFed SS316L parts possessed a negative strain rate. In contrast, the simultaneous attainment of maximum Ultimate Tensile Strength (UTS) and ductility was possible in the quasi-static strain rate.

Machine learning approach on the prediction of mechanical characteristics of pristine, boron doped and nitrogen doped graphene

Machine Learning (ML), a subset of Artificial Intelligence has been widely applied in various domains, but it has only just begun to be employed in the field of engineering. In the present investigation, various ML algorithms and artificial neural network (ANN) structures are used for the first time to predict the mechanical properties of pristine, boron-doped, and nitrogen-doped graphene while also taking into account the effects of various types of vacancy defects. Fracture strain, Ultimate Tensile Strength (UTS), and Young’s modulus are all predicted. ML technique reduces the computational cost and time required to find out mechanical properties of these materials. The training dataset for the ML models is developed using Molecular Dynamics (MD) simulations. It was shown that defects and doping both had an adverse effect on mechanical characteristics. While ANN, LASSO, and LASSO Lars have all performed quite well at predicting these features, pipeline polynomial regression has performed best across all datasets. New insights on the research of mechanical characteristics utilizing cutting-edge computational techniques are provided by the discoveries in this research.

The effect of oxide scale and microstructural changes during cyclic hot corrosion on high-temperature tensile properties of Rene-80 superalloy

ABSTRACT The effect of oxide scale and microstructural changes during 10, 20, and 40 hot corrosion cycles on the high-temperature tensile properties of Rene-80 superalloy at 950 °C was investigated. Due to the formation of micro-cracks and micro-voids, compressive stresses produced from Cr2O3 and NiO growth, and tensile stresses stemming from NiMoO4 transformation and Al internal oxidation, the oxide scale spalled. By increasing the hot corrosion cycles, UTS (Ultimate Tensile Strength) and El.% (Elongation) first decreased and then increased due to the propagation of intergranular vertical cracks from the oxide scale to the Rene-80 after 20 cycles. During hot corrosion cycles, YS increased due to a rise in the density of near-surface intergranular cracks close to the Rene-80/oxide scale interface resulting from micro-void linkage and γ′-depleted zone. Due to the high area fraction and the small average size of secondary γ′, UTS and YS were the highest and lowest after ten cycles, respectively.

Impact of Electric-Arc Welding on The Mechanical Properties of AISI 1055 Medium Carbon Steel with Varied Gauge Diameters

Purpose: This paper investigated through experimentation, the impact of electric-arc welding processes on the mechanical properties of AISI 1055 steel medium carbon steel material with varied gauge diameters.
 Design/Methodology/Approach: The study used experimental and analytical methods to investigate the impact of electric arc welding on the mechanical properties of AISI 1055 Medium Carbon Steel. The test samples were prepared based on the standards of the American Iron and Steel Institute (AISI), with varied gauge diameters. Standard tensile tests were performed on the samples before welding and after welding, using a computer-interfaced Universal Tensile Testing Machine. Data obtained from the study was analyzed using graphs, tables and charts. Finally, the sets of results for both welded and unwelded specimens were compared to determine the impact that welding has on welded medium carbon steel components and structures.
 Findings: The data recorded by the computer-interfaced tensile test machine was used to plot and display, the stress-stain graphs for the various sets of samples. The results showed that the welding processes adversely affected the Ultimate Tensile Strength (UTS), Yield Strength, Elastic Modulus and Impact Strength of the samples studied; since all the samples studied had their initial values dropped after undergoing welding and testing. However, the strain of the samples increased after welding.
 Research Limitation/Implication: Although there are other methods and techniques of welding metals, this study adopted electric arc welding to weld the samples used for the study due to resource constraints.
 Practical Implication: The findings of this study also bring to the fore, the need for industry regulators to promulgate standards to regulate the welding of medium carbon steel and by extension, other industrial materials to preserve the natural properties of the materials.
 Originality/Value: This study introduced an important perspective to the testing of engineering materials by varying the gauge diameters (a key determinant of the dimensional specifications of the specimen), to obtain a comprehensive insight into the impact of electric-arc welding on the mechanical properties of the material.

Use of hardness, PIP and tensile testing to obtain stress-strain relationships for metals

Both hardness testing and Profilometry-based Indentation Plastometry (PIP) can be used to obtain features of (tensile) stress-strain curves. The two tests are superficially similar, involving penetration (under a known load) of an indenter into the flat surface of a sample, followed by measurement of dimensional characteristics of the residual indent. The associated data handling procedures, however, are very different in the two types of test. Hardness numbers, which are commonly based on measurement of the lateral extent or depth of the indent, essentially give a semi-quantitative indication of the resistance to plastic deformation: going beyond this to infer features of the (nominal) stress-strain curve – notably the yield stress (YS) and Ultimate Tensile Stress (UTS) – can only be done via empirical correlations (often restricted to certain types of alloy). PIP testing, on the other hand, involves measurement of the complete indent profile, followed by (automated) iterative FEM modelling of the indentation, allowing the complete (true) stress-strain curve to be obtained. This paper covers application of both approaches to 12 different alloys, with inferred stress-strain characteristics being compared with those from tensile testing. Insights are provided relating to the very different levels of detail and reliability offered by the two procedures.

Microstructure, mechanical and fracture properties of friction stir welded 2195 Al-Li alloy joints

The 8 mm-thick 2195 Al-Li alloy joints were achieved by Friction Stir Welding (FSW). The microstructural evolution, temperature-dependent mechanical properties, and fracture properties were studied. The T1, δ′/β′ and θ′ precipitates were observed in the Base Metal (BM) and the Heat Affected Zone (HAZ). Most of the precipitates, except for re-precipitated δ′/β′ phases, were dissolved in the Nugget Zone (NZ). The tensile specimens that failed at cryogenic temperatures (–196 °C) had the maximum Ultimate Tensile Strength (UTS), and the fracture surface showed the inter-granular fracture characteristics. Compared to those at room temperature (25 °C), the decreasing tensile properties at high temperature (180 °C) were related to microstructure and strain hardening effects. The NZ presented the optimal fracture toughness, and the Crack Tip Opening Displacement (CTOD) was mutually dominated by microhardness and grain size. Analysis on Fatigue Crack Growth (FCG) rates indicates that the Thermal-Mechanically Affected Zone (TMAZ) exhibited the most superior fatigue resistance performance at stress intensity range below 17 MPa·m1/2 due to compressive residual stress and the crack closure effect. The fatigue fracture surfaces reveal that the crack propagation zone was characterized by the striations and secondary cracks. Also, inter-granular fracture behavior was responsible for the fastest FCG rates in the NZ.

Study on Mechanical Behaviour of Al-15Si-10Zn/x ZrO2 Composites Synthesized by Stir Cast Method

In this research, the microstructure and mechanical properties of Al-15Si-10Zn-xZrO2 (x = 5, 7 and 10 wt.%) composites synthesized by the stir-casting process have been investigated. The matrix and composite samples were characterized using an X-ray diffraction test (XRD) and their microstructures were studied using optical microscopy and scanning electron microscopy (SEM). The microstructure of different phases was analyzed using energy-dispersive spectroscopy (EDS). The microstructure of the Al-15Si-10Zn/ZrO2 composites consisted of coarse primary Si, needlelike eutectic Si, and Zn-rich phases, with ZrO2 reinforcement particles distributed homogeneously in the composites. The micro-hardness and tensile properties of the matrix and composites were determined at room temperature. The results show significant improvements in the micro-hardness and tensile strength of the composites compared to the matrix alloy. The micro-hardness of the stir-cast composites increased by 24%, 44%, and 58% in the 5, 7, and 10 wt% ZrO2 reinforcement composites, respectively. The ultimate tensile strength (UTS) of the 5, 7, and 10 wt% ZrO2 composites increased by 17%, 30%, and 44%, respectively, compared to the matrix alloy. The increased content of ZrO2 resulted in an increase in hardness, ultimate tensile and yield strengths and a decrease in ductility.

Experimental and Theoretical Justification of the Foam Fiber-Reinforced Concrete Application Expediency in Earthquake-Resistant Construction

Introduction. Based on the evolutionary approach to the analysis of the lightweight concrete application expediency in earthquake-resistant construction it has been revealed that development of the above mentioned technologies fosters the reduced material consumption in construction and the increased durability of buildings under the seismic loads. The efficient solutions for constructing the earthquake-resistant buildings are constantly searched for, and the reasons for reducing the range of energy-efficient products made of the autoclaved aerated concrete are noticed. The research is aimed at compiling an inventory of modern technological methods of increasing the buildings seismic resistance.Materials and Methods. The list and properties of raw materials used for single-stage technology manufacture of the foam concrete mixtures have been provided. The list of equipment used for assessing the studied materials’ mechanical properties has been defined.Results. The new experimental data confirming the significant influence of the individual properties of fiber on the value of the dispersedly reinforced foam concrete ultimate deformability and bending tensile strength has been obtained. The positive effect of the length of fiber on the foam concrete mechanical properties has been confirmed. The considerably positive effect of the dispersed reinforcement on the homogeneity of mechanical properties observed in the foam concrete mass has been distinguished.Discussion and Conclusions. The work performed has elucidated the importance of the individual properties of fiber as a tool for managing the operational properties of foam concrete. The ultimate properties of the aerated rock material are influenced by the length of fibers and their ultimate deformability. The length of fiber is important for the bending tensile strength, whereas the values of this parameter in the composite material are regulated by the ultimate extensibility.

Evaluation of metallurgical and mechanical characteristics of the ferritic stainless steel AISI 430 produced by GTAW-based WAAM

In this work, AISI 430 ferritic stainless steel (FSS) was produced in multi-layered wall form using gas tungsten arc welding (GTAW) based wire arc additive manufacturing (WAAM), and the mechanical and metallurgical performance was evaluated. Ferrite microstructure was found on the as-printed steel with deleterious phases and needle-shaped martensite structure. The microhardness variation of the WAAM deposited steel is found to be 200–240 HV at different regions of the entire cross-sectional area. The tensile test was done on the steel to determine the ultimate tensile and yield strength, reported as 565 ± 3 and 306 ± 1 MPa. The tensile fractured surface shows the existence of more and deeper dimples which illustrates the ductile failure.