Properties Of High-manganese Steel Research Articles

Effects of titanium addition on austenite grain size and mechanical properties of high manganese steel

Manganese steels have been widely used in industries due to their good wear resistance, high work hardening ability, and high toughness and ductility. This research investigated the effect of modification, i.e., FeTi and Mischmetal, on the grain size and mechanical properties of the high manganese steel (13–15 wt.%). The alloys are modified at different temperatures of 1500, 1550, and 1600 o. The modified alloys were heat-treated after solidification by a two-step process. The grain size, chemical composition, and phase formation of the heat-treated steel were characterized by Optical Microscopy, X-ray Diffractometry, and Energy-Dispersive X-ray Spectroscopy. The mechanical properties of the steel, such as Brinell hardness, tensile strength, and toughness, were measured. As a result, the grain size of the heat-treated alloys is smaller compared to that of un-modified alloys and decreases with the increase in modification amount. The addition of Ti reduced C in the austenite phase by forming very stable carbides, TiC. Maximum tensile strength of 780 MPa was achieved with the addition of 0.1 wt.% Ti, while maximum fracture toughness was 140 J/cm2 at 0.05 wt.% Ti.

A Review of Influencing Factors of Damping Properties of High Manganese Steel

High manganese steel has wide prospects in industry due to their excellent mechanical and damping properties. The quenching structures of high manganese steel are ε-martensite, γ-austenite and α'-martensite. Researches show that the damping properties of high manganese steel are related to these microstructures. Besides, there are many ways to improve the damping property of damping alloys. This paper reviews the damping mechanism and the influences of the ad-dition of alloying elements, heat treatment, pre-deformation and other factors on their damping performance, hoping to provide methods and ideas for the study of damping properties of high manganese steel.

Factors Affecting the Mechanical Performance of High Manganese Austenitic Steel

High manganese austenitic steel has attracted increasing attention for its application in liquefied natural gas storage tank materials due to its excellent ductility and low cost. This paper presents an overview of the research progress of high manganese austenitic steel in recent years. As a structural material used at a low temperature environment, high manganese steel should not only have certain strength, but also good toughness to prevent brittle fracture at a low temperature. In this work, factors affecting mechanical properties of high manganese steel are discussed, possible reasons for the deterioration of low-temperature properties are analyzed, and the strengthening and toughening mechanisms of materials are elaborated, which may be beneficial to improve properties of high manganese austenitic steel.

Effects of gating design on structural and mechanical properties of high manganese steel by optimizing casting process parameters

Effects of gating design on structural and mechanical properties of high manganese steel by optimizing casting process parameters

Changes in the Mechanical Properties and Microstructure of High Manganese Steel by High Heat Input Welding and General Welding Processes

The demand for liquefied-natural-gas-fueled tanks on ships is growing in accordance with IMO 2020 regulations. The use of high manganese steel has increased recently, as this material can be applied at cryogenic service temperatures according to IGF code and has economic advantages over other materials. In this study, the high heat input welding process, which involves one-side submerged arc welding (SAW) welding with cut wire, is investigated to increase the productivity of high manganese fuel tank welding. The Flux cored arc welding and SAW welding processes are also evaluated and compared with the high heat input welding process. The mechanical properties of high manganese steel satisfied the class requirements and no precipitates were found in the weldment and heat-affected zone.

Microstructure and wear properties of high manganese steel by V-Ti alloying elements

High manganese steel was prepared by adjusting the components of the alloys by adding V-Ti. The investigation was carried out to study the effect of V-Ti elements alloying on the microstructure and wear properties of high manganese steel through metallographic microscope, scanning electron microscopy, mechanical machine and abrasive wear tests. The test results showed that V-Ti alloying improved the properties of high manganese steel. The grains are refined, size of impurities are reduced, the form and distribution of impurities are also ameliorated. In addition, the hardness was increased by 23.7%~84.6% and tensile strength can be increased up to 31.3%.

Study of the relationship between stacking fault energy and microstructure in different compositions of Fe-Mn steels produced by weld deposit

The properties of high manganese steels are usually related to the mechanism of austenite deformation, either martensite or twin formation during deformation. This deformation mechanism is often related to the stacking fault energy (SFE) that the material possesses. Studies show that SFE values between 0 and 8 mJ/m2; provide formation of ε martensite during deformation, whereas only twins are formed for energies above 18 mJ/m2. Intermediate values provide the formation of both ε martensite and twins. In this way, it is possible to predict the microstructure and, consequently, mechanical properties with the knowledge of the material’s SFE. In this work, a weld consumable with high manganese content was deposited on a SAE 1012 carbon steel plate with the flux-cored arc welding process producing different chemical compositions and consequently different SFE that varied as a function of the dilution. Low dilution conditions led to austenite and ε martensite formation in the molten zone, while in high dilution conditions, α’ martensite were found, besides those other two. Manganese was found to be the most influential element in the phase formation change, based on SFE and SFE components analysis.

Effect of Element Addition and Heat Treatment Process on the Properties of High Manganese Steel

The changing of properties of HMnS by alloy elements addition and heat treatment was presented. Studying about the hardness of HMnS were increased when the Mn contents increased. On the other hand, the Cr content has effective on the hardness and microstructure of this steel also, but with the Cr content was increased from 2% to 2,5%, the hardness of high Manganese steel was not much changed. With the research about HMnS, it was added the Cr and applied the advanced heat treatment process, the microstructure of this steel was formed the chrome carbide particles with grain fine which dispersed in the matrix with the formation of these dispersed carbide particles will contribute to increasing the alloy's abrasion resistance. With the difference in heat treatment processes, the microstructure and hardness were also changed. When the sample was heat-treated according to the model heat treating; the particle size of the sample is also significantly reduced. This explains why the hardness value of the sample increases significantly. Also, under the impact load, on the surface layer of this steel, the microstructure does not appear the martensite structure form but only see the twinning on the surface. These are new findings on the mechanism transformation of high manganese austenite steel when working under the impact of the impact force. The mechanism of transformation is quite different from the previous view of phase transformation under the impact force of high manganese austenitic steel.

INOCULATION OF HIGH MANGANESE STEEL CASTINGS USING TITANIUM CARBONITRIDE

The article is devoted to study of the process of mold inoculation of high manganese steel castings using titanium carbonitride. Introduction considers basic principles, alloying and inoculation of casting alloys. Review of the papers on this topic made by native and foreign researchers was given. Conclusions were made on the materials presented in the studied papers, goals and tasks for studies were formed. Besides, in this part of the article relevance of the conducted researches was substantiated as well as practical significance for casters. The second part of the article describes routine of experiments. Materials involved when conducting experimental works were considered in details: charge materials, treatment agent, materials for foundry molds. Besides, there are also described the way to receive experimental cast products, methodology to determine thermal conditions for forming experimental models in foundry mold and regimen of thermal treatment. Herewith, methodology for conducting metallographical test was considered. The third part of the article mentions the results received during carrying out experimental works on mold inoculation using fine titanium carbonitride powder of high manganese steel castings. Influence of inoculation on the level of performance properties expressed via coefficients of abrasive wear and wear striking resistance was considered as well as change of the indicated peculiarities in relation to not inoculated alloy was evaluated. Besides, results of metallographical tests were given which allowed to substantiate change of the performance properties level of high manganese steel. Influence of thermal conditions of forming cast products was also evaluated, in particular speed of alloy cooling in foundry mold on the level of performance properties of inoculated high manganese steel. In final part of the article conclusions on the results of conducted researches were made as well as manufacturing recommendations were given for practical implementation of the work results to increase the level of performance properties of high manganese steel. Besides, recommendations on the most reasonable expenditure of titanium carbonitride powder ensuring receipt of the necessary characteristics of microstructure and as a consequence, increase of the level of performance properties were given.

Effect of Titanium Alloying on the Microstructure and Properties of High Manganese Steel

The test used casting process to alloy the traditional high manganese steel with adding Ti. The surface morphology of the high manganese steel sample was observed by the scanning electron microscopy.At the same time, the hardness, the tensile strength and the wear resistance of the sample were tested. Compared with the high manganese steel without alloying, it studied the micro-structure and properties of modified high manganese steel . The results show that the grain of high manganese steel alloyed by titanium alloy is refined, the inclusions is dispersed and their size is reduced. The hardness of high manganese steel is increased by 87 %~263 %, but the tensile strength is reduced. Compared with the sample without added titanium element, the wear resistance of the alloyed high manganese steel is significantly improved.

Microstructure and Mechanical Properties of High Manganese Steel Processed by Cold Working and Aging at 4.2 K

High manganese steel is a promising choice as a jacket material for Nb3Sn superconducting magnet due to the low thermal expansion, high strength combined with good ductility. One kind of high manganese steel with the Mn content of about 21% was developed for reviewing the mechanical properties at 4.2 K. In this paper, the mechanical performances of the developed high Mn steel in solution annealed as well as in cold worked and aged condition were tested. Influences from cold working and aging processes on microstructure and mechanical properties were analyzed.

Effects of Chromium Content and Impact Load on Microstructures and Properties of High Manganese Steel

In this paper, the effects of Cr content and impact load on the microstructure and properties of High Manganese Steel (HMS) were investigated. The results show that the hardness of HMS was increasing when the Cr content increased, but the hardness was not much changing when the Cr contents changed from 2% to 2,5% of weight. Under the impact load, the microstructure and the hardness were changed also. The Cr content effected on the depth of transition layer on surface under the impact load and the twinning occurred during impacting load.

Precipitation Processes in High-Manganese Steels

The highly interesting properties of high manganese steels can be further improved by microalloying. The introduction of carbon-nitride precipitates improves the yield strength and the microstructural control during the production process. Due to the high manganese content in these austenitic steels significant changes in the precipitation behaviour have to be expected in comparison to conventional carbon-manganese steels. However, although crucial for steel design, this has not been systematically described before. Preliminary results showing the effect of Nb and V are presented. Namely the softening behaviour is related to the precipitation state. In summary this allows describing the precipitation-time-temperature evolution and provides the necessary background for the alloy and process design.

Influence of rolling conditions and aging process on mechanical properties of high manganese steels

Three laboratory cast and rolled high manganese steels with different Mn (in the range of 24–28wt%), C (in the interval of 0.2–1.2wt%) and Al (from 2.3wt% to 12wt%) contents has been investigated. Differences in chemical compositions, rolling conditions and followed by aging process at the temperature of 500°C and four different aging dwells (in the range of 6min to 60min) have led to various k-carbides precipitation. The k-carbides have been responsible for the mechanical properties. The intragranular type of nano-size has increased the strength, respectively hardness level whereas the k-carbides nucleated in the intergranular form have reached size of micrometre and in lower volume fraction have not been importantly able to increase the matrix hardness, especially in case of lower C portion. Balanced Mn, C and Al contents for optimised k-carbides precipitation have been also discussed. The materials were hot rolled to strips of 1.9mm in thickness from the heating temperature of 1100°C using the rolling mill Tandem.

In Situ Characterization of Deformation Behavior of Austenitic High Manganese Steels

AbstractThe mechanical properties of high manganese steels are linked to their hardening mechanisms and their intrinsic behavior during deformation. The characterization of mechanical properties is influenced by the localization of plastic flow and the effect of this localization on the material. Depending on grain size, temperature, and extrinsic strain rate localization of strain, adiabatic heating, and hardening vary in spatial and temporal extent. Even at small strain rates the adiabatic heating of samples reaches temperatures more than 100 K over initial testing temperature due to the sharp localization and last but not least this heating is also dependent on the tested sample size. Furthermore, temperature influences the activated mechanisms of plastic flow. The characterization of temperature increase, strain distribution, and local hardening is pursued in tensile tests with application of infrared thermography. With those techniques it is possible to gather correlations between local strain and temperature. The analysis of dynamic strain ageing effects is also carried out by evaluation of the instantaneous strain rate, the strain rate in the gauge length, in dependence of stress in different alloys, as well as at different strain rate regimes. Thus it is possible to distinguish the onset of TRIP, TWIP and DSA.

Improvement of the Mechanical Properties of High Manganese Steels by Combination of Precipitation Hardening and Mechanical Twinning

Twinning-Induced Plasticity steels (TWIP steels) are extensively studied due to their ultra-high strain-hardening rate, that brings about a remarkable combination of ductility and strength. Twinning can be observed in high manganese-carbon steels. This paper considers hardening by combination of mechanical twinning with carbide precipitation. The kinetics of precipitation and the morphological evolution of carbides with annealing time were studied for two different TWIP steels with high manganese and carbon contents. The steels are first cold-rolled and then annealed at 800°C for recrystallization and carbide precipitation. Depending on the steel composition, the kinetics of precipitation and the morphology of the carbides are quite different. The influence of the annealing cycle on the mechanical properties has also been assessed. The results are used to discuss the influence of composition, stacking fault energy (SFE) and carbide precipitation on twinning. We show that the usual criteria based on the SFE only are not sufficient to characterize the twinning ability of a steel.

Effect of aging and plastic strain on the mechanical properties of high manganese steel

1. Aging of high-manganese 110G13L steel at temperatures from 200 to 400°C permits to increase its ultimate strength without changing the yield stress, while plastic properties, and the semibrittleness temperature T50 slightly decrease. Aging at temperatures above 400°C leads to sharp reduction of σB, ψ, δ and T50. 2. After fractional loading of the 110G13L steel at temperatures of 20–250°C an increase of σ0.2 and σB is achieved; the plastic properties decrease in cold strain while in thermal strain they do not change. 3. The process of plastic strain of the 110G13L steel with subsequent aging causes an increase of strength properties without reducing plasticity. Apparently this takes place on account of the separation during aging of dispersed particles along the slip planes, produced by preliminary deformation.

Effect of vanadium on the structure and properties of high-manganese steels

Vanadium has a substantial effect on the structure and properties of manganese steels. It leads to an increase in the quantity of carbides and greatly increases the effect of dispersion hardening of austenite. Aging is particularly effective for steels with a high concentration of manganese (10–13%) and vanadium (>4%).

Properties of high-manganese steel after forging

Properties of high-manganese steel after forging

Effect of deformation temperature and heat treatment on the structure and properties of high-manganese steel

Effect of deformation temperature and heat treatment on the structure and properties of high-manganese steel