High Manganese Steel Research Articles

Corrosion Resistance Comparison of High Manganese Steel in 0.01mol/L NaHSO3 Solution and 3.5wt.% NaCl Solution

Corrosion Resistance Comparison of High Manganese Steel in 0.01mol/L NaHSO3 Solution and 3.5wt.% NaCl Solution

Preparation and properties of ZTA/alloyed high manganese steel composites

In the long-term use of high manganese steels, it is not desirable to achieve wear resistance by austenite deformation strengthening alone. The wear resistance of high manganese steel is much lower than that of ordinary wear-resistant steel under medium and low stress conditions. Improving the instability of wear resistance caused by defects in high manganese steels is an important problem to be solved in current industrial production. In this study, a new type of high manganese alloy with high hardness and high wear resistance was prepared by multi-alloying with Cr-W-Mo elements on the basis of 20Mn1.2C. ZTA ceramic particles reinforced high manganese steel composites were prepared by selecting high manganese steel materials with excellent mechanical properties as the metal matrix of ceramic reinforced metal matrix composites. The Cr-W-Mo multi-alloyed high manganese alloys are mainly composed of a mixed austenite and ferrite matrix, M3C-type cementite and M6C-type carbides. The Cr2W6Mo6 sample has the best overall mechanical properties. Its hardness reached 49.8 HRC, which is 1.20 times higher than that of the Cr2 sample. The mass loss was 0.2571 g, which is 79.92% of the Cr16 sample (0.3217 g). The ZTA ceramic particles were well composited with the alloyed high manganese steel matrix, and the thickness of the interfacial layer was 20-30 μm, with the formation of Mn2AlO4 and (Fe, Mn)2SiO4, and (Al, Cr)2O3 in the interfacial layer. The best abrasion resistance was obtained at a ZTA content of 40 vol.%. The mass loss was 0.1669 g, which is 51.88% of the Cr16 material (0.3217 g).

Evaluation of the depth and degree of work hardening during rough turning of high-manganese steel

Evaluation of the depth and degree of work hardening during rough turning of high-manganese steel

Elemental segregation, microstructure, and mechanical properties of TMCP-treated high-manganese wear-resistant steel

Elemental segregation, microstructure, and mechanical properties of TMCP-treated high-manganese wear-resistant steel

Experimental investigation on effect of cooling rate on carbide precipitation during solidification of high manganese steel

In order to elucidate the effect of cooling rate on the carbide formation during the solidification process of high manganese steel Mn13, the solidification process is artificially divided into two stages, namely the liquid-solid phase transition stage and solid-state cooling stage. The final Mn13 samples with different cooling rates are used to the analysis of solidification structure and carbides by high-temperature confocal microscopy (HTCLSM), optical microscopy (OM), electron backscatter diffraction (EBSD), and scanning electron microscopy (SEM). The result shows that the change of cooling rate at the liquid-solid phase transition stage has a great influence on the solidification structure and carbide precipitation. At this stage, with the increase of cooling rate from 0.2 °C/s to 5.0 °C/s, the dendrite structure is obviously refined, and the secondary dendrite arm spacing and cooling rate are satisfied with the relationship: λΠ=54.14×v−0.33. Also, the average grain size in the Mn13 sample decreases from 549 μm to 346 μm, and the aspect ratio of gains in the Mn13 sample increases from 1.7 to 2.0. Moreover, the distribution of carbide in the interdendritic regions and grain boundaries increases, and the morphology of carbide at the grain boundary change from block to dendrite. But it seems that the change of cooling rate from 1 °C/s to 5.0 °C/s at the solid-state cooling stage has a slight effect on the secondary dendrite arm spacing, the average size and aspect ratio of the grain structure and the amount and morphology of carbide precipitation at the grain boundary.

Effect of the strain rate on the deformation mechanisms of TWIP-type steel

This paper describes the influence of the strain rate on the microstructure of X55MnAl25-5 steel from the group of high-manganese steels exhibiting the twinning-induced plasticity effect. The tests were carried out at a wide range of strain rates, starting with static tensile tests where the appropriate strain rates were 0.005 s−1, and ending with tests using a flywheel machine at strain rates of 1830 s−1 and 4650 s−1. The increase in the applied strain rate on the example of the tested steel results in hardening. Evolutionary changes leading to the predominance of dislocation slipping over the twinning are observed in the microstructure under static deformation conditions. The increase in the intensity of twinning with the simultaneous decrease in the mobility of dislocations progresses as the strain rate increases. The microstructure evolution was characterized using light optical microscopy and scanning electron microscopy, including electron backscatter diffraction. The qualitative analysis of the deformation twins was performed. For the lowest strain rate, 5·10−4 s−1, deformation twins appear in a single twinning system, while increasing the strain rate leads to the activation of multiple twinning systems. Proceeding to the range of dynamic tests reveals an increase in the participation of the twinning mechanism in the deformation of the examined steel. With an increasing strain rate, the effect of texture on the twinning process activity decreases. Based on the obtained results, a diagram was elaborated that presents the microstructural changes which take place in X55MnAl25-5 steel after deformation under static and dynamic tensile conditions in graphical form.

Microstructure and properties of in situ TiCP/Mn18Cr2 architecture composites

In situ TiC ceramic particle-reinforced steel matrix composites, typically produced via liquid metal infiltration of unstructured preforms, often demonstrate issues with composite areas being prone to fracture. To address this problem, particles with an average diameter of 3 mm were constructed and used to fabricate preforms. Using the in situ self-generation method, the composites were then synthesised with liquid Mn18Cr2. To control the degree of in situ spontaneous reaction, moderator alloy powders at concentrations of 20, 30, 40 and 50 wt.% were utilised. The results reveal that the TiC particle size in the composites gradually decreases as the moderator concentration in the preform increases, reducing from 1.31 to 0.92 μm. The microhardness and elastic modulus at the composite interfaces are intermediate between those of the TiC ceramic particles and the high manganese steel matrix. The inclusion of millimetre-scale architecture enhances the tensile strength of the composites, with tensile strength gradually increasing as the moderator content decreases. This study offers a comprehensive understanding of how moderator content influences the microstructure and mechanical properties of TiC-reinforced Mn18Cr2 composites, providing valuable insights for the development of high-performance structural materials.

Microstructure and cryogenic mechanical properties of dissimilar friction stir welding joints between nitrogen-alloyed CoCrFeMnNi high-entropy alloy and high-manganese austenite steel

The microstructures and cryogenic mechanical properties of dissimilar friction stir welding (FSW) joints between nitrogen-alloyed CoCrFeMnNi high-entropy alloys (HEAs) and Fe–32.1Mn–7.5Cr–0.6Mo–1.2 N steel were investigated. The results reveal that defect-free dissimilar joints can be achieved through FSW. Furthermore, the grains of nitrogen-alloyed CoCrFeMnNi HEAs in the stir zone of the dissimilar joint are significantly more refined than those of Fe–32.1Mn–7.5Cr–0.6Mo–1.2 N steel. Joint efficiency at room and low temperature both exceed 90% of the base metal. Moreover, the cryogenic yield and ultimate strength of the dissimilar joints are higher than those recorded at room temperature. The fracture position is at the heat-affected zone of HEAs under two temperature conditions.

Deformation strengthening mechanism of laser remelted high manganese steel

In order to further improve the deformation hardening ability of high manganese steel (HMnS) under low stress or small deformation, a low speed laser remelting technology was proposed to process the HMnS surface. Through parameters optimization, microstructure characterization, wear testing, and deformation strengthening analysis, the deformation strengthening mechanism of laser remelted HMnS (LR-HMnS) was systematically studied, and excellent wear resistance properties was also achieved. Firstly, by optimizing the parameters of laser remelting, high-quality microstructures with large remelting depth and fewer porosities were obtained. Then, the sliding wear tests showed that although the surface hardness of LR-HMnS (252.83HV0.3) was only 2.56 % higher than that of continuous casting HMnS (CC-HMnS) (246.53HV0.3), its volume wear rate (1.87×10−5 mm3/N·m) was only 10 % of CC-HMnS (18.71×10−5 mm3/N·m), which exhibited excellent wear resistance properties. Finally, for quantitative evaluating its work hardening at high strain rates, Hopkinson compression test of LR-HMnS was conduced according to the operating conditions of HMnS parts. The microstructure after small compression deformation was analyzed using EBSD and TEM. It was found that the larger grain size of LR-HMnS was helpful of reducing the nucleation stress of twins, forming high-density nano-twins, high-density stacking faults, and high-density dislocations. The synergistic effect of stacking faults, dislocations, and twins which segmented the matrix and refined the grains, and achieved the dynamic Hall-Petch effect. The superior deformation strengthening and wear resistance exhibited by larger grain HMnS were called the inverse grain size effect. Additionally, the large number of C-Mn strong bond networks formed by element segregation could enhance the pinning effect of dislocations, promote deformation hardening rate and wear resistance properties under low stress or small deformation. The research results provided a new method for pre-hardening of HMnS, and will also expand the application potential of HMnS in combined conditions of high, medium, and low impact.

Correlation of austenite grain size with ε-/α′-martensitic transformation and mechanical properties in a high-manganese damping steel

One of the core studies on low stacking fault energy (SFE) high-manganese steel is to maintain excellent damping capacity while achieving high strength and toughness. The austenite grain size (AGS) in high-Mn steel affects its SFE and even the strength-plasticity and damping capacity of the steel, but the detailed mechanism related to martensitic transformation has not been clarified. In this study, Fe-17Mn high-Mn damping steel is used as the material to obtain austenite grains of different sizes by controlling the cold rolling and annealing processes. By using in-situ tensile testing, damping capacity testing, and various microscopic analytical techniques, the influence of AGS on the thermal/deformation induced martensitic transformation, work hardening behavior, mechanical properties and damping capacity of the steel is mainly studied. The results indicate that the refinement of austenite grain increases the SFE of high-Mn damping steel and reduces the amount of thermal induced ε-martensite (εth) and stacking faults (SFs). The deformation induced martensitic transformations (DIMTs) in high-Mn damping steel during tensile deformation include γ→εD, εth→α′ and εD→α′ transformation. The deformation induced ε-martensitic transformation is more helpful to improve the work hardening rate than deformation induced α′-martensitic transformation. Due to the concentration of strain partitioning at grain boundaries, twin boundaries and phase boundaries, refinement of austenite grain can promote deformation induced ε-martensitic transformation and improve the steel strength. However, excessively small austenite grains can suppress deformation induced α′-martensitic transformation leading to a significant decrease in elongation. Under the synergetic effects of grain refinement strengthening and multiple martensitic transformations, when the average AGS is about 4.0 μm, the steel has high strength and high plasticity, with a tensile strength of 919 MPa, a yield strength of 518 MPa and an elongation of 46.4 %. The product of tensile strength and elongation is up to 42.6 GPa·%. At low or high strain amplitudes, the damping capacity of this steel shows an opposite trend with the refinement of AGS. The damping capacity of the steel gradually increases with grain refinement at low strain amplitudes of 0.01 %–0.065 %, mainly due to the reduction of the content of weak pinning points. At high strain amplitudes of 0.065 %–0.1 %, the damping capacity of the steel gradually decreases for the reduction of damping sources with the refinement of grain size.

Temperature Effect on Deformation Mechanisms and Mechanical Properties of Welded High-Mn Steels for Cryogenic Applications.

High-manganese steel (high-Mn) is valuable for its excellent mechanical properties in cryogenic environments, making it essential to understand its deformation behavior at extremely low temperatures. The deformation behavior of high-Mn steels at extremely low temperatures depends on the stacking fault energy (SFE) that can lead to the formation of deformation twins or transform to ε-martensite or α'-martensite as the temperature decreases. In this study, submerged arc welding (SAW) was applied to fabricate thick pipes for cryogenic industry applications, but it may cause problems such as an uneven distribution of manganese (Mn) and a large weldment. To address these issues, post-weld heat treatment (PWHT) is performed to achieve a homogeneous microstructure, enhance mechanical properties, and reduce residual stress. It was found that the difference in Mn content between the dendrite and interdendritic regions was reduced after PWHT, and the SFE was calculated. At cryogenic temperatures, the SFE decreased below 20 mJ/m2, indicating the martensitic transformation region. Furthermore, an examination of the deformation behavior of welded high-Mn steels was conducted. This study revealed that the tensile deformed, as-welded specimens exhibited ε and α'-martensite transformations at cryogenic temperatures. However, the heat-treated specimens did not undergo α'-martensite transformations. Moreover, regardless of whether the specimens were subjected to Charpy impact deformation before or after heat treatment, ε and α'-martensite transformations did not occur.

Microstructures and mechanical properties of additively manufactured Fe–30Mn–3Al–3Si TWIP steel using laser powder bed fusion

Twinning induced plasticity (TWIP) high manganese steel demonstrates high ultimate tensile strength (UTS) and ductility, but its low yield strength limits its applications. This study presents the additive manufacturing of Fe–30Mn–3Al–3Si TWIP steel using laser powder bed fusion (LPBF) with enhanced mechanical properties. The average grain size of the LPBF-fabricated Fe–30Mn–3Al–3Si was 5.4 ± 1.3 μm, which was only one-tenth of that of a wrought one. In-situ formed Al-rich oxide nanoparticles were observed to be uniformly distributed in the matrix. The size of the oxide nanoparticles was about 30 nm with a volume fraction of about 0.9 %. The tensile yield strength was 554 ± 3 MPa and the UTS was 837 ± 7 MPa with an elongation of 41.5 ± 2.6 % for horizontal direction. Low anisotropy was observed for LPBF-fabricated Fe–30Mn–3Al–3Si. Compared with the wrought Fe–30Mn–3Al–3Si, the yield strength was increased by 140 %. This work provides a benchmark for the additive manufacturing of high manganese steel.

Effects of Ultrasonic Nanocrystal Surface Modification on Surface Hardening Mechanism and Wear Behavior of Additively Manufactured High-Manganese Steel

Effects of Ultrasonic Nanocrystal Surface Modification on Surface Hardening Mechanism and Wear Behavior of Additively Manufactured High-Manganese Steel

The effect of chromium on the corrosive performance of novel high manganese steel frogs in a simulated industrial atmosphere

Abstract The corrosion behavior of three novel high manganese steel frogs with different Cr contents in a simulated industrial corrosive atmospheric environment is studied through the corrosion weight gain, x-ray diffraction (XRD), scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS), and electrochemical testing. The results indicate that the content of Cr in the steel affects the phase composition, density, and electrochemical stability of the rust layer. For instance, as the Cr content increases, the content of the amorphous phase in the rust layer continuously increases while that of γ-FeOOH decreases, leading to enhanced density and electrochemical stability of the rust layer. The study reveals that Cr exists in the rust layer in the form of Cr2O3 and Cr(OH)3, providing nucleation cores to nanoscale colloidal rust particles. Consequently, a higher Cr content leads to more nucleation cores, which improves the density of the rust layer and enhances the corrosion resistance of the novel high manganese steel frogs in industrial corrosive atmospheric environments.

Effect of final rolling temperature on the microstructure and properties of high-manganese austenitic low-temperature steel

The effect of final rolling temperature ranging from 962 to 696 °C on as-rolled high-Mn austenitic low-temperature steel was investigated using scanning electron microscopy, electron backscatter diffraction, transmission electron microscopy, and X-ray diffraction. The microstructure of the experimental steel remained austenite without suffering ferrite phase transformation, even when produced with a final rolling temperature as low as 696 °C. A decrease in the final rolling temperature of the steel was accompanied by a decrease in grain size from 20.2 to 6.0 μm, accompanied by an increase in dislocation density from 3.01 × 1014 to 10.9 × 1014 m−2. In addition, M23C6 carbides precipitated at the grain boundaries when the final rolling temperature was below 782 °C. Grain refinement and increased dislocation density significantly enhanced the strength of the material. However, an increase in the intragranular dislocation density compromised grain deformation ability. Moreover, the precipitation of M23C6 reduced the plasticity and toughness of the material. Considering the balance between yield strength and low-temperature toughness, the optimal final rolling temperature was 898 °C; this produced a material with a yield strength of approximately 507 MPa and a low-temperature impact energy absorption of approximately 143 J.

Study on the Relationship Between Humidity and Under-Deposit Corrosion in High Strength Medium Manganese Steel

Study on the Relationship Between Humidity and Under-Deposit Corrosion in High Strength Medium Manganese Steel

Stress corrosion cracking behavior and mechanism of high manganese steel in inshore SO2-polluted marine environment

Stress corrosion cracking behavior and mechanism of high manganese steel in inshore SO2-polluted marine environment

Advance on rock-breaking cutter steels: A review of characteristics, failure modes, molding processes and strengthening technology

Rock breaking has always been a challenging problem that must be solved in projects such as excavating mountains, drilling wells, and constructing railways. Among the rock-breaking cutter steels, AISI H13 steel and wear-resistant high manganese steel have become the best choices. From the characteristics and failure modes of the two, rock-breaking cutter steels should simultaneously have high strength, high toughness and high wear resistance to avoid short-term fracture/damage and cost increase. Analyzing the problems existing in the molding process of rock-breaking cutter steels such as die casting, forging, and hot stamping, traditional strengthening technologies such as alloying optimization, heat treatment, and surface treatment can achieve certain performance enhancement. After reaching the limits of traditional strengthening technologies, a series of nanoparticle strengthening technologies came into being. The selection, addition amount, and addition method of nanoparticles all affect the microstructure, mechanical properties and wear. To this end, this article summarizes the research progress and challenges of rock-breaking cutter steels, and discusses traditional strengthening technologies and mainstream nanoparticle strengthening technologies. It provides a reference for the future development of high-quality and high-performance rock-breaking cutter steels, with aim to simultaneously expand their application potentials to other fields.

Microstructures and mechanical properties of additively manufactured Fe–21Mn-0.6C TWIP steel using laser powder bed fusion

Twinning induced plasticity (TWIP) high manganese steel exhibits high ultimate tensile strength (UTS) and ductility, but its low yield strength restricts its applications. This research presents a Fe–21Mn-0.6C TWIP steel with enhanced mechanical properties additively manufactured using laser powder bed fusion (LPBF). The average grain size of the LPBF-fabricated Fe–21Mn-0.6C was 17.1 μm in the vertical direction, which was a quarter of that of a wrought one. The tensile yield strength was 657 MPa and the UTS was 1089 MPa with an elongation of 47.9% for the vertical direction. Compared to the wrought Fe–21Mn-0.6C, the yield strength increased by 110%. The high strength of LPBF-fabricated Fe–21Mn-0.6C is primarily attributed to solution, grain boundary and dislocation strengthening. Serrations were observed in the stress-strain curves at the initial stage of deformation, showing large stress drops. In the annealed sample, serrations appeared at a later stage of deformation with little stress drops. This difference in serration phenomenon is attributed to the varying dislocation density in the two samples.

Machine learning and experimental study on a novel Cr–Mo–V–Ti high manganese steel: Microstructure, mechanical properties and abrasive wear behavior

Machine learning combined with traditional experimental methods can promote the efficient research and development of materials. In this work, five kinds of algorithm models combined with a genetic algorithm (GA) were used to optimize the compositions of the alloyed high manganese steel. And then the effect of solid solution temperatures on the microstructure, mechanical properties, and impact wear properties of the steel were systematically investigated. The results showed that Categorical Boosting (CB) model exhibited the high validation accuracy (R2 > 0.95, RMSE<4.11, MAE<2.44). Based on the trained CB model and GA, the optimal steel compositions were obtained. The as-cast microstructure of the steel contained coarse austenite, little pearlite and networks and irregular carbides. After water toughening treatment, the pearlite completely dissolved into the matrix and the number of carbides gradually decreased. Compared to as-cast alloy, the austenite grain size significantly decreased, and it decreased first and then increased with the increase of solid solution temperatures. The average impact energy, ultimate tensile strength (UTS) and elongation (EL) of the steel increased and then decreased with the increase of solid solution temperatures. However, the wear loss showed an opposite trend. The steel of water quenching at 1100 °C with an average impact energy of 185.1 J, hardness of 242.4 HBW, UTS of 742 MPa, yield strength (YS) of 458 MPa, and EL of 37.4%, exerted best impact toughness, mechanical properties and wear resistance. It was attributed to the interactions among dispersed small sized second phases, high density dislocations, fine austenite grains and twins.