Chromium-nickel Stainless Steel Research Articles

Research of the microstructure glass–metal boundary obtained under influence by ultrashort pulse lasers

The article research the microstructure of the welded layer obtained by exposure to an ultrashort laser pulse on a glass-metal joint. The study of the weld made it possible to identify the effect of thermal diffusion of the chemical elements of glass and metal into the joint zone in a ratio of 50 : 50% of each material. The size of the transition layer of the welded joint between glass and metal was 2–3 microns. The results of the work also show that when combining chromium-nickel stainless steel with borosilicate glass, bonds of the Fe–O–Si type are formed, and the connection of a 6000 series aluminum alloy with borosilicate glass leads to the formation of aluminum oxides Al2O3.

The effect of the method for producing chromium-nickel stainless steel powders on the strain state and properties of the outer cage of a spherical hinge joint

The paper substantiates the relevance of studying powder metallurgy methods and efficiency of applying them to the production of spherical bearings of highly loaded spherical hinge joints. It proves that the force and work of deformation, as well as the kinetics of forming of the outer cage of a spherical hinge joint made of sintered corrosion-resistant chromium-nickel steels, are influenced by the chemical composition of powders and lubricants, the protective environment and the method of sintering, the microstructure and mechanical properties of the workpiece material. It is shown that the plastic properties of ring specimens under testing depend on the perfection of interparticle contacts, the presence and distribution of chromium oxides, forming schemes and workpiece porosity. The influence of the method for the production of stainless chromium-nickel powders on the density and mechanical properties of the sintered blanks is studied. A method is proposed for evaluating the strain state during radial deformation of ring specimens made of these steel powders and estimating the maximum allowable values of strain intensity below which no cracks are formed during cold forming of porous blanks. It is revealed that, to calculate the stress state and, accordingly, strain resistance in the cold forming of the outer cages of spherical hinge joints, made of sintered corrosion-resistant steels, it is possible to use the known constitutive equations if strain intensity does not exceed the experimentally obtained limit values. The feasibility of implementing the proposed method and selecting the process parameters of cold forming of spherical hinge parts made of chromium-nickel austenitic steels is substantiated.

Mechanical and Metallurgical Properties of Dissimilar Joining of 304 ASS: A Review

The mechanical and metallurgical properties of dissimilar joining of 304 stainless steel (SS) and other alloys have been extensively studied in recent years. Stainless steel is a widely used material in various industries such as aerospace, chemical processing and transportation. The austenitic Chromium-Nickel stainless steel AISI 304 provides the best balance of corrosion resistance, endurance, and ductility. Due to the low carbon content, carbide precipitation during welding is less likely. The dissimilar welding of AISI 304 austenitic stainless steel using various welding techniques with various materials was thoroughly reviewed in the current paper. According to the review, the optimum material to use when intergranular corrosion is a concern is AISI 304 austenitic stainless steel. It is also among the best materials usually utilised in the production of components that cannot be heated.

Investigation of corrosion behavior of welded area of austenitic stainless steel under different environments

Stainless steel 316 has excellent corrosion resistance when exposed to different corrosive environments and medium. It is usually regarded as marine grade stainless steel and it is not resistant to the warm sea water. The corrosion behavior of welded austenitic chromium-nickel stainless steel was investigated with different welding process under different solutions or different environments. The corrosion loss measured by the weight loss method, optical microscopy and scanning electron microscopy. Austenitic stainless steel was welded by the Arc welding, MIG welding and TIG welding and these weld specimens were investigated by using three different acids which has highly corrosive properties such as Ferric chloride(FeCl3), Oxalic acid, Nitric acid (HNO3). These acids are taken as 1 N concentration for rapid corrosive. The weight loss was measured by 24 h once for 12 days. The micro structure of stainless steel was captured by optical microscopy and scanning electron microscopy and the lowest and highest rate of corrosion was observed.

Stochastic-Based Reliability Analysis of Stainless-Steel Beams Under Bending

The presented article studies the bending resistance of a stainless steel hot-rolled profile UPE 80, which is stressed by bending around the minor principal axis. Resistance is studied as the random output variable, which is a function of input material and geometric characteristics. The paper deals with the stochastic analysis of this static resistance. The computational model is created on the basis of the finite element method using geometric and materially nonlinear solution. The Ansys software with 4-node Shell 181 element is used. The input random variables of the stainless steel are taken from previous research aimed at identifying the material mechanical properties based on experimental research of austenitic chromium-nickel stainless steel 1.4307/AISI 304 L. Statistical analysis is performed using the Latin Hypercube Sampling method. The probability of achieving standard design resistance is estimated and compared with the reliability level in standard EN1990 given by the reliability factor beta 3.8. The article discusses the need for a larger number of samples for reliable estimates of design resistances and for the verification of partial reliability factors, which are a challenge for further research.

Global Sensitivity Analysis of Ultimate Limit States of Stainless Steel Structural Members

The article presents global Sobol sensitivity analysis of a rolled member in tension made from austenitic chromium-nickel stainless steel of type 1.4307/AISI 304 L. The statistical characteristics of yield strength and of the geometry of the rolled steel IPE cross-section are presented on the basis of published experimental research. The sensitivity analysis showed the dominant effect of the yield strength on the static resistance. The second dominant variable is the flange thickness. Higher-order sensitivity indices oriented at detecting the presence of interaction effects between input variables are very small. The characteristics of other types of sensitivity analyses oriented at quantiles or the probability of failure are discussed, especially in terms of a higher proportion of higher-order sensitivity indices. The results of Sobol sensitivity analysis of stainless steel are compared with similar results of carbon steels.

Effect of SLM process parameters on hardness and microstructure of stainless steel 316 material

Selective laser melting (SLM) is an additive manufacturing process in which layers of metallic powder are selectively melted and fused by a high-powered laser to form near-fully dense 3D components. The SS316L is an austenitic chromium-nickel stainless steel containing a deliberate amount of molybdenum which increases general corrosion resistance and especially improves its pitting resistance to chloride ion solutions. The importance of process parameter such as layer thickness and orientation of specimen on the hardness and microstructure are being explored. Hence, it is essential to carry out research in that direction. The aim of the study is to understand the effect of layer thickness and angle orientation on hardness of the material as it is one of the desirable properties for SS316 material. The excellent hardness (218.835 BHN) was attained at the angle orientation of 90° and layer thickness of 40 µm according to ANOVA analysis.

AK STEEL 309S

Abstract AK Steel 309S is a chromium-nickel austenitic stainless steel that provides excellent corrosion resistance and heat resistance in addition to good strength at room and elevated temperatures. It is identical to AK Steel 309 except for a lower carbon content that minimizes carbide precipitation and improves weldability. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, and joining. Filing Code: SS-1334. Producer or source: AK Steel Corporation.

AK STEEL 309

Abstract AK Steel 309 is a chromium-nickel austenitic stainless steel. It is typically used for elevated temperature applications. Its high chromium and nickel contents provide comparable corrosion resistance, superior resistance to oxidation, and the retention of a larger fraction of room temperature strength than the common austenitic stainless steels, such as type 304. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, and joining. Filing Code: SS-1333. Producer or source: AK Steel Corporation.

Effects of pre-creep on dislocation and tensile property of Cr-Ni steel

Pre-creep experiments were performed on chromium-nickel (Cr-Ni) stainless steel in the early stage of creep. The temperature was held for 500–2000 h under high-temperature load conditions (873 K and 150 MPa), and various analysis methods, including optical microscopy, electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), and X-ray diffraction, were used to determine the pattern of dislocation evolution under different temperature-holding times. The results showed that the slip bands intersected at the initial stage of pre-creep, and a quadrilateral network structure was formed by the dislocation pinning. As the temperature-holding time increased, the dislocation network began to climb to form dislocation walls, dislocation cells, and other substructures. At 2000 h, the grain boundaries widened considerably; creep holes were found at the grain boundaries; and dislocation pairs with oscillating contrast occurred, which indicates nitrogen diffusion. The yield and tensile strengths of the Cr-Ni steel samples subjected to pre-creep at holding times of above 1000 h decreased after they were subjected to room-temperature tensile tests.

Influence of Process of Straightening Ship Hull Structure Made of 316L Stainless Steel on Corrosion Resistance and Mechanical Properties

Abstract The AISI 316L type steel belongs to the group of chromium-nickel stainless steels. They are determined according to European standards as X2CrNiMo17-12-2 and belong to the group of austenitic stainless steels. Steels of this group are used for elements working in seawater environments, for installations in the chemical, paper, and food, industries, for architectural elements, and many others. The chemical composition of corrosion-resistant austenitic steels provides them with an austenite structure that is stable in a wide temperature range, under appropriate conditions for heating, soaking, and cooling. 316L steel plate was subjected to a technological treatment of hot straightening with an oxy-acetylene torch, which is not commonly used for this type of steel, mainly due to the lack of objective assessment of whether the austenitizing temperature has been achieved and the stability of the heat treatment process is ensured. The single-phase structure of austenite with high corrosion resistance, without precipitation of carbides, steel is obtained by supersaturation in water from 1100°C. The purpose of the presented research was to determine the usefulness of the flame straightening process for a ship structure made of 316L steel.

Evaluation of resistance to corrosion cracking of irradiated austenitic chromium-nickel steels by impact bending tests on miniature specimens

In this work, we present results of a bending test of miniature specimens made of chromium-nickel stainless austenitic steels of grades 321 (08Kh18N10T), 316 (06Kh16N11M3) and 304 (02Kh18N9) irradiated to various damage doses from 4 to 125 dpa in different energy neutron spectra. Effects of the damage dose and the neutron energy spectrum on the intergranular fracture energy, which determines the strength of grain boundaries, are studied. Two neutron spectra are considered: one characteristic of the active zone of PWR and WWER reactors, and the other is typical for the active zone of fast core reactors. The relationship between the resistance to corrosion cracking of irradiated chromium-nickel steels 321, 316 and 304 and the strength of grain boundaries is considered.

AK STEEL TYPE 304L

Abstract AK Steel Type 304L is a chromium-nickel austenitic stainless steel. It is an extra low-carbon variation of Type 304 with a 0.030% maximum carbon content that eliminates carbide precipitation due to welding. As a result, this alloy can be used in the “as-welded” condition, even in severe corrosive conditions. In many cases it eliminates the necessity of annealing weldments except for applications specifying stress relief. Type 304L has slightly lower mechanical properties than Type 304. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fatigue. It also includes information on high temperature performance, corrosion resistance as well as forming, heat treating, and joining. Filing Code: SS-1324. Producer or Source: AK Steel Corporation.

ATI 309S (UNS S30908)

Abstract ATI 309S (UNS S30908) is a chromium-nickel austenitic stainless steel that is typically used for elevated-temperature applications. The alloy’s high chromium and nickel contents provide comparable corrosion resistance, superior resistance to oxidation, and the retention of a larger fraction of room temperature strength than the common austenitic alloys such as Type 304. This datasheet provides information on composition, physical properties, and tensile properties. It also includes information on corrosion resistance as well as forming, machining, and joining. Filing Code: SS-1318. Producer or source: ATI.

AK STEEL TYPE 304

Abstract AK Steel Type 304 is a chromium-nickel austenitic stainless steel. It is a variation of the base 18-8 grade, but with higher chromium and lower carbon content. The lower carbon content minimizes carbide precipitation due to welding and reduces its susceptibility to intergranular corrosion. Type 304 is the most versatile and widely used stainless steel grade. It combines good resistance to atmospheric corrosion and to many chemicals, food, and beverages. It has excellent formability. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties as well as fatigue. It also includes information on low and high temperature performance, and corrosion resistance as well as forming and joining. Filing Code: SS-1317. Producer or source: AK Steel Corporation. Originally published April 2020, corrected May 2020.

Защитное последействие ингибитора ИФХАН-92 при коррозии хромоникелевой стали в серной кислоте

The protective polymolecular layers formed on the surface of 12Kh18N10T chromium-nickel stainless steel in a solution of sulfuric acid with IFKhAN-92 (a triazole derivative) added is shown to have the protective afteraction in the same acid. The effectiveness of the protective afteraction of mixtures containing IFKhAN-92 is determined by the time of preliminary adsorption of the inhibitor, its concentration in the solution of preliminary adsorption, the temperatures of the solution of preliminary adsorption of the inhibitor and the background acid solution. The layers formed on steel by the IFKhAN-92 + KNCS and IFKhAN-92 + KI compositions have the highest protective afteraction. These layers protect steel at 80 °С in the background 2 M H2SO4. An increase in temperature of the solutions of preliminary adsorption of inhibitors enhances their protective afteraction, which indicates chemical nature of the interaction of the inhibitor molecules with the steel surface. The composition and the structure of the protective layers formed on the steel surface was studied by XPS analysis. The protective layer is chemically bonded to the phase of hydroxides and oxides of Fe, Cr and Ni, adjacent to the metallic phase. The lower part of the protective polymolecular layer of the organic inhibitor consists of a polymer complex formed by molecules of IFKhAN-92 and metal cations (Fe, Cr and Ni). The outer part of the protective organic layer consists of physically adsorbed molecules IFKhAN-92, easily removed from the metal surface during ultrasonic washing of samples.

Application of Cold Metal Transfer Welding for High Pressure Die Casting Mold Restoration

This paper presents results of the research focused on the possibility of the restoration of the shape parts of molds made of X15CrNiSi20-12 (EN 100 95) heat-resistant austenitic chromium-nickel stainless steel working in high-pressure die casting of aluminum alloys by clad welding. There were tested two welding wires—E Ni 6625 and E 18 8 Mn B 2 2—deposited on X15CrNiSi20-12 (EN 100 95) tool steel using cold metal transfer (CMT) welding in a protective atmosphere of Ar. The resistance of welds was tested against dissolution in molten aluminum alloy ENAC-AlSi9 and the testing procedure was designed. The resistance of welds against dissolution were assessed by exposition of welded clads in an aluminum melt for 120 and 300 min. The EDX semi-quantitative microanalyses of element distribution were performed at the welding–melt interface, and build-ups were also observed on the surface of welded clads.

Composite metal oxide coatings on chromium-nickel stainless steel produced by induction heat treatment

Metal oxide coatings were formed by induction heat treatment (IHT) on the surface of 12Cr18Ni10T stainless steel. The phase composition of these coatings comprised oxides of alloying elements, such as CrO2 (rutile-type phase), NiO, and slight amount of other oxides (Cr2O3, Fe2O3, Fe3O4). Nanosized morphology parameters were determined on the surface of steel samples with coatings subjected to low temperature IHT at T = 800–850 °C. The average size of nanograins was about 30–80 nm at an exposure within t = 30 s. The equivalent hardness value (Vickers scale, HV) of the near-surface layer was 445 ± 10 HV, which was slightly lower than the initial hardness value of untreated 12Cr18Ni10T steel. Hardness of the metal oxide coatings themselves H = 10.86 ± 4.47 GPa determined by the nanoindentation method was almost 4 times higher than the initial hardness of the steel surface. In vitro testing for biocompatibility of the metal oxide coatings confirmed that high morphological heterogeneity of the surface ensured excellent adhesion of cells.

Residual Stresses, Microstructure, and Mechanical Properties of EB-Welded 90-mm-Thick UNS S41500 Martensitic Stainless Steel after PWHT

Abstract UNS S41500 is a grade of 13Cr-4Ni martensitic stainless steel utilized in hydroelectric turbine products. In this study, the microstructural characteristics, mechanical properties, and through-thickness residual stresses of electron-beam (EB) welded butt joints in 90-mm-thick UNS S41500, assembled using a single pass autogenous process, were evaluated after post-weld heat treatment (PWHT). The results of the longitudinal residual stresses, measured using the contour method, indicated that the applied PWHT was effective in stress relieving and reducing the hardness of the weldment through tempering of the “fresh” martensite present in the microstructure after EB welding. The static tensile properties that were evaluated in the directions transverse and longitudinal to the weld seam demonstrated high performance of the joints with conformance to the requirements of not only ASME Section IX, ASME Boiler & Pressure Vessel Code–Section IX: Qualification Standard for Welding and Brazing Procedures, Welders, Brazers, and Welding and Brazing Operators, but also ASTM A240, Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications, for unwelded UNS S41500. The Charpy impact energies indicated that the toughness of the welds greatly surpassed the minimum acceptance criteria specified in ASME Section VIII, ASME Boiler & Pressure Vessel Code–Section VIII: Rules for Construction of Pressure Vessels. Also, bend testing of transverse weld cross sections displayed no discontinuities on the tension side of the bent joints. These results provide the essential data for validating a manufacturing process for assembly of high-performance joints in an important hydroelectric turbine material.

Synthesis and investigation of highly dispersed active phases of intermetallic and supported SHS-catalysts

In the present study, the active phases (AP) of an Fe–Ni–Co–Mn catalyst produced from SHS-intermetallics (a), a catalyst prepared via formation an intermetallic layer on a mesh surface of chromium-nickel stainless steel (b), and of a Co–Mn catalyst prepared via SHS on silica gel support (c), were isolated and characterized by SEM and XRD. The catalysts studied were highly active in the process of deep oxidation and catalysts (b) and (c) were highly active in the process of CO2 methanation as well. All AP had oxo-metallic composition and were formed from nanoscale components, but if the structure of these components for catalyst (a) was the same as on the surface of the catalyst, the structures of AP components for catalyst (b) significantly differed from the surface structures. In addition, AP sediment grain nanostructures of catalyst (c) differed from those of catalysts (a) and (b).