Properties Of Steel Research Articles

Ballistic analysis of high-performance armor steel by numerical simulation

In order to establish a connection between the ballistic performance and mechanical properties of armor steel, a ballistic simulation model was developed and subsequently validated for accuracy and reliability. The mechanical properties of the target plate were described using the Johnson–Cook constitutive relation. An analysis was conducted to investigate the impact of the J–C parameters of the target plate on its ballistic performance, revealing a strong linear relationship between them. Subsequently, a mathematical model represented as H = 14.82 − 0.0048A − 0.0023B + 5.95n − 81.3C was derived, and its accuracy was demonstrated to exceed 90%. This mathematical model can effectively predict the ballistic performance of the armor steel, even when its mechanical properties undergo variations during the production process. This prediction capability significantly contributes to reducing research costs and time.

Dual Antibacterial Properties of Copper-Coated Nanotextured Stainless Steel.

Bacterial adhesion to stainless steel, an alloy commonly used in shared settings, numerous medical devices, and food and beverage sectors, can give rise to serious infections, ultimately leading to morbidity, mortality, and significant healthcare expenses. In this study, Cu-coated nanotextured stainless steel (nSS) fabrication have been demonstrated using electrochemical technique and its potential as an antibiotic-free biocidal surface against Gram-positive and negative bacteria. As nanotexture and Cu combine for dual methods of killing, this material should not contribute to drug-resistant bacteria as antibiotic use does. This approach involves applying a Cu coating on nanotextured stainless steel, resulting in an antibacterial activity within 30min. Comprehensive characterization of the surface revealing that the Cu coating consists of metallic Cu and oxidized states (Cu2+ and Cu+), has been performed by this study. Cu-coated nSS induces a remarkable reduction of 97% in Gram-negative Escherichia coli and 99% Gram-positive Staphylococcus epidermidis bacteria. This material has potential to be used to create effective, scalable, and sustainable solutions to prevent bacterial infections caused by surface contamination without contributing to antibiotic resistance.

Formation and growth of transition metal carbides in ferrite

Carbide nano-precipitates are commonly used to improve mechanical properties of steel. It has been experimentally observed that TiC, NbC, and VC carbide precipitates initially form as ‘plate-like’ particles oriented in the {100} planes of the ferrite lattice. These platelets share similarities with Guinier-Preston zones in Al-Cu alloys.The clustering of group IV and V transition metal atoms (M = Ti, Zr, Hf, V, Nb, Ta) in ferrite is studied using density functional theory. It is deduced that the transition metal carbides all form in a similar way. Furthermore, the transition from an initial M–C cluster to a NaCl-structured platelet to a NaCl-structured precipitate is examined through atomistic simulations using Modified Embedded Atom Method potentials. A route is established along which transition metal carbides form and transform into precipitates that possess the Baker-Nutting orientation relation with the ferrite matrix.

Effect of hydrogen on microstructure evolution and properties of high-strain pipeline steel under cyclic strain loading

The microstructure evolution and the fatigue damage mechanism of hydrogen-charged high-strain pipeline steel during the cyclic strain loading is studied. Hydrogen promotes the formation of dislocation walls and cells, and causes the lattice distortion iron atoms to move to the grain boundary, resulting in grain refinement. The fatigue life is reduced to more than 40% when the strain amplitude reaches 0.5% after hydrogen-charged. The main reasons for the reduce are the decrease of the number and the change of propagation mode of secondary cracks, and the increase of cleavage fracture and the decrease of deflection angle in the main cracks.

Bending Properties of Cold-Formed Thin-Walled Steel/Fast-Growing Timber Composite I-Beams

A cold-formed, thin-walled steel/fast-growing timber composite system has recently been presented for low-rise buildings. It aims to increase the use of fast-growing wood as a green building material in structures, thus contributing to the transformation of traditional buildings. This study proposed a composite I-beam combined with fast-growing radiata pine and cold-formed thin-walled U-shaped steel. A four-point bending test was used to measure the bending properties of steel–timber composite I-beams under various connection methods. Based on experimental results, this study examined the specimen’s failure mechanism, mechanical properties, and strain development. In addition, a method for calculating flexural bearing capacity based on the superposition principle and transformed section method was suggested. It is evident from the results that fast-growing timber and cold-formed thin-walled steel can have significant composite effects. Different connecting methods significantly impact beams’ failure mode, stiffness, and bearing capacity. Furthermore, the theoretical method for calculating the flexural bearing capacity of composite beams differs from the test value by less than 10%. This paper’s research encourages the applications of fast-growing wood as light residential components, and it serves as a reference for the development, production, and engineering of steel–timber composite structural systems.

The effect of deformation temperature in metastable austenite zone on microstructure evolution, mechanical and corrosion properties of high Cr ferritic-martensitic steel

The effect of deformation temperature in metastable austenite zone on microstructure evolution, mechanical and corrosion properties of high Cr ferritic-martensitic steel

Effect of duplex surface treatment on the impact properties of maraging steel produced by laser powder bed fusion

The impact properties of an L-PBF 18Ni-300 maraging steel were investigated after different heat and duplex (nitriding and PVD coating) surface treatments. Impact energy is almost isotropic. Contrary to expectations, impact energy is not decreased by surface treatments, since the effect of surface embrittlement of nitriding is compensated by the increase in the austenite content. An important role is played by the geometry of the notch where the surface hardening is lower than in the flat surface of the Charpy specimens.

Performance Assessment of Quenchants on Mechanical Properties of Steel Grade A1046

The main aim of the study is to assess the performance of ghee oil, coconut oil and sea water quenchants on mechanical properties of A1045 steel. The procedures comprise the production of tensile steel specimens, heat-treat them into electrical oven at 850°C for one hour, quench them in ghee oil, coconut oil and sea water separately. The quenched samples were again tempered separately at the temperature of 400°C. Then all the specimens taken for the mechanical tests such as hardness, tensile, impact test and also to calculate the percentage of elongation, having completion of tests, microstructural analysis had conducted to view the structures contain in each specimen. The results obtained on these processes determine whether these oils can be used as local industrial quenchants. The facilities required for the research is include material testing laboratory, heat treatment workshop, machine shop and metallographic laboratory to mentioned but a few. The material selection is steel grade A1045, that have been normally utilize in metal industries for the production of machine parts and structural components

Effect of direct aging heat treatment on microstructure and mechanical properties of Laser Powder Bed Fused Maraging steel 300 grade alloy

Abstract This paper investigates the effects of a 6-hour direct aging heat treatment at 490°C on the mechanical, tribological, and microstructure characteristics of laser powder bed fused maraging 300 steels, which is produced at various laser energy densities. After direct aging heat treatment, the grain boundaries become irregular and vague due to the residual stress releasing, squeezing of precipitates into the grain boundaries, and phase transformations. The XRD analysis reveals the reverted austenite (γ') phase forms during age treatment due to the inevitable reversion of metastable martensite to the stable reverted γ' phase. The heat-treated samples microhardness rises with rising the Laser Energy Density (LED) from 61.33 to 92.10 J/mm3 due to a decrease in the reversed austenite phase and a further rise in LED decreases the microhardness due to a rise in the reversed austenite phase. The heat-treated sample produced at LED of 92.10 J/mm3 shows maximum yield, ultimate tensile strengths, and minimum elongation percentage due to its high microhardness, and the fractography results show the failure mode as a mixed brittle and ductile fracture. The wear rate of the heat-treated additively manufactured maraging 300 steel decreases as the LED increases from 61.41 to 92.1 J/mm3 and a further rise in LED increases the wear rate. The wear rate rises with a rise in sliding velocity from 1.5-3.5 m/s. The dominant wear mechanism was observed as abrasion with small grooves and saplings.

Performances of the sandwich panel structures under fire accident due to hydrogen leaks: Consideration of structural design and environment factor using FE analysis

Abstract This study presents a comprehensive analysis using the finite element method (FEM) to examine and evaluate the behavior of fuel carrier ship structure. Sandwich panels are effective structures for use in ship structures due to their lightweight yet robust nature. Sandwich panels used in ship structures have various core shapes, such as hexagonal, circular, and square, as needed. The sandwich panel structure can be widely implemented in ship construction, for example, on the deck, hull, and bulkhead of the ship’s cabin. Hydrogen is an alternative fuel that can replace fossil fuels. In this modern era, hydrogen is high valuable energy commodity, so accidents involving carrier ships could have significant consequences. Hydrogen is produced from liquefied natural gas (LNG), so if a leak occurs, for instance, in a storage tank or fuel tank, it has the potential to lead to accidents such as fires. Corrosion is a significant concern for the maritime industry, as it can jeopardize the structural integrity of these vessels and pose substantial safety and environmental risks. In this research, FEM was utilized to model and simulate the effects of corrosion on hydrogen carrier ships when exposed to fire, considering various environmental and operational factors. Through a systematic investigation, it is aimed to gain insights into the impact of corrosion on ship structural components during fires, such as hulls and storage tanks. The result of this study will contribute to improving corrosion and fire mitigation strategies, ensuring the safety and longevity of hydrogen and LNG carrier ships, and supporting the sustainable transportation of hydrogen to meet global energy demands. No research has been conducted on the structural behavior resulting from hydrogen fires and corrosion simultaneously. To achieve this, it is assumed to use the corrosion properties of steel in heavily traveled ship routes such as the Panama Canal Zone, Barent Sea, North Sea, and Suez Canal Zone. This study utilized an approach by modeling corrosion using shell thickness in Abaqus Quasi-Static and applying boundary conditions in the form of temperature increase up to 800°C and subsequent cooling back to the initial temperature. At the maximum temperature, the most significant mid-span displacement occurred in the circular core sandwich panel, with a value of 4 mm. The axial force in the structure was inversely proportional to the mid-span displacement. In the case of the circular core sandwich panel, the axial force was 96 kN. The most resilient core type was hexagonal because it experiences the least deformation when compared to circular and square cores.

Effect of process parameters on joint quality and mechanical properties of local-thickened self-piercing riveted steel and die-casting aluminum joints

Effect of process parameters on joint quality and mechanical properties of local-thickened self-piercing riveted steel and die-casting aluminum joints

Intervention mechanism of carbide precipitation during tempering and its impact on residual stress and mechanical properties of wear-resistant steels

The production of low-stress, high-performance wear-resistant steels poses a formidable challenge in the steel industry. This article delves into the carbide precipitation behaviour of wear-resistant steel NM300TP during tempering and its subsequent impact on residual stress and mechanical properties. Our findings reveal a crucial aspect: prolonging the holding time can interfere with the precipitation behaviour of carbides, thereby altering the relaxation mechanism of residual stress and its influence on material properties. Remarkably, we discovered that substituting the formation of θ-cementites with the precipitation of ε-transition carbides can yield a steel with significantly lower residual stress while maintaining exceptional mechanical properties. Specifically, when θ-cementites precipitate, the residual stress in the wear-resistant steel diminishes by 54.23%, accompanied by a hardness measurement of 299.58 HV0.5. However, when a substantial quantity of ε-transition carbides is dispersed and precipitated, the residual stress is further diminished by 69.51%, and the hardness reaches 317.2 HV0.5. Furthermore, this precipitation of ε-transition carbides exhibits superior wear resistance compared to θ-cementites. These groundbreaking discoveries offer critical theoretical insights for the development of low-stress, high-performance wear-resistant steels, paving the way for innovative advancements in the steel industry.

Properties of stainless steel and its application in construction

Properties of stainless steel and its application in construction

Effect of Quenching Cooling Rate on Hydrogen Embrittlement of Precipitation-Hardened Martensitic Stainless Steels

Effect of Quenching Cooling Rate on Hydrogen Embrittlement of Precipitation-Hardened Martensitic Stainless Steels

Effect of Welding Heat Input on the Mechanical Properties of Mild Steel at Coarse Grain Heat Affected Zone (CGHAZ)

Effect of Welding Heat Input on the Mechanical Properties of Mild Steel at Coarse Grain Heat Affected Zone (CGHAZ)

A Study on the Microstructural Evolution, Interfacial Diffusion and Mechanical Properties of Ultra-thin Stainless Steel–Copper Composites Fabricated by Roll Bonding

A Study on the Microstructural Evolution, Interfacial Diffusion and Mechanical Properties of Ultra-thin Stainless Steel–Copper Composites Fabricated by Roll Bonding

Melting mode driven tuning of local microstructure and hardness in laser powder bed fusion of 18Ni-300 maraging steel

Laser powder bed fusion (LPBF) of 18Ni-300 maraging steel has attracted abundant popularity in both academia and industry due to its superior mechanical properties and printability. Several studies showcased the optimization of process parameters based on relative density, but there is little exploration on tailoring the as-built microstructure. In this study, fully dense maraging steel samples are fabricated with three different melting modes, and they are examined for the cellular solidification microstructure, retained austenite, and the effect of cyclic reheating, the three characteristics that are unique to additively manufactured maraging steel. Microstructural discrepancies among the samples are traced back to the different cooling rate and residual heat, both of which are ultimately determined by the energy input. The findings suggest that a reasonably low energy input yields a microstructure containing fine cell size and little retained austenite, leading to higher hardness. Nanoindentation mapping reveals that the main bodies of all samples are strengthened around 13 %, likely because of the formation of precipitation zone due to four to five layers of subsequent cyclic reheating. This study demonstrates the important opportunity for microstructural tailoring, and consequently, engineering the mechanical properties of maraging steel via LPBF by controlling the solidification and subsequent cyclic reheating, which are both attributed to the printing parameters deployed.

Susceptibility of X17CrNi16-2 martensitic stainless steel to hydrogen embrittlement after conventional and deep cryogenic heat treatment

A low carbon/ high chromium martensitic stainless steel, X17CrNi16-2, was heat treated using two different hardening and tempering regimes (1050 °C/480 °C or 980 °C/600 °C) — promoting either a high strength or high toughness state, respectively − and further combined with deep cryogenic treatment (DCT) at −196 °C for 24 h. Over recent years DCT has been recognized as a promising technique to improve the properties of steel, predominantly with respect to its tensile strength, toughness and wear resistance. The influence of DCT on the hydrogen embrittlement resistance of martensitic stainless steel has not yet, however, been reported.A slow strain rate tensile test (SSRT) with simultaneous cathodic hydrogen charging was selected as the method to assess potential susceptibility to hydrogen embrittlement (HE). Relatively low-intensity hydrogen charging, utilizing a constant current density of 0.1 mA/cm2, in a non-corrosive, slightly alkaline buffer solution, led to a clear reduction in the ultimate tensile stress. This reduction, and therefore the HE susceptibility, was more pronounced in the steel with a higher strength (i.e. that subject to the 1050 °C/ 480 °C heat treatment condition). Furthermore, DCT did not appear to have any impact on the steel’s mechanical properties in the presence of hydrogen. Fractographic analysis showed clear evidence of HE in the hydrogen-charged specimens.This paper presents results of the SSRT tests and further fractography results, and discusses the impact of conventional and deep cryogenic treatment on HE susceptibility.

Effect of Ni content on microstructure and mechanical properties evolutions of 9Cr high Si heat resistant steel deposited metals

This work presents the effect of Ni content on the morphology of microstructure and changes of mechanical properties of high Si 9Cr heat resistant steel deposited metals with different states: as-welded, as-post weld heat treated (750 °C/2.5 h) and as-aged (550 °C/3000 h). With the increase of Ni content, the martensitic laths are refined improving the overall mechanical properties. δ ferrite deteriorates the impact toughness. During aging process, Ni facilitates the formation of M6X. Therefore the overall mechanical properties of deposited metal decreases as the Ni content increases after long-term aging owing to the formation of chain-like precipitates consisted mainly of M6X. The process of post weld heat treatment improves the negative effect of small-sized δ ferrite on impact toughness.

The influence of the hydrogenation process on the microstructure and properties of metallic materials

Hydrogen, which belongs to the group of the smallest elements, can freely penetrate the structure of metallic materials and cause enormous damage. This phenomenon may occur due to various conditions and may have different effects on the properties of materials. Understanding these mechanisms is important in the era of changing to alternative energy sources. This situation may occur in combustion engines powered by hydrogen-enriched fuel. The work analyzed the impact of various hydrogenation processes on the properties of aesthetic steel, which is allergic to the formation of carbides at the grain boundaries, such a microstructure is intended to simulate the least favorable working conditions. The work was aimed at evaluating the effects of different hydrogenation methods on changes in the properties of the AISI 310s steel membrane. In the work, electrolytic hydrogenation and heat treatment procedures in a hydrogen atmosphere were used. Investigations of changes in material properties included microhardness and in-situ strength tests in a scanning electron microscope chamber. Research has shown that both processes increase the hardness of materials and change the characteristics of stretching curves.