Development and Properties of ε-Martensite in Co-Cr-Mo Alloys for Biomaterials Applications

Preferred orientation of rolling-induced ε martensite in an Fe-Mn-Si alloy

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:2003902 ◽

2003 ◽

Vol 112 ◽

pp. 365-368 ◽

Cited By ~ 6

Author(s):

K. K. Jee ◽

W. Y. Jang ◽

Y. H. Chung

Keyword(s):

Preferred Orientation ◽

Ε Martensite

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Effect of the γ→ε Phase Transition on Transformation-Induced Plasticity (TRIP) of Nickel-Free High Nitrogen Steel at Low Temperatures

Metals ◽

10.3390/met11050710 ◽

2021 ◽

Vol 11 (5) ◽

pp. 710

Author(s):

Natalia Narkevich ◽

Yevgeny Deryugin ◽

Yury Mironov

Keyword(s):

Volume Fraction ◽

Tensile Load ◽

X Ray Diffraction ◽

High Nitrogen Steel ◽

Transformation Induced Plasticity ◽

X Ray ◽

Root Cause ◽

Nitrogen Steel ◽

Ε Phase ◽

Ε Martensite

The deformation behavior, mechanical properties, and microstructure of Fe-Cr-Mn-0.53%N austenitic stainless steel were studied at a temperature range of 77 up to 293 K. The dynamics of the steel elongation were non-monotonic with a maximum at 240–273 K, when peaks of both static atom displacements from their equilibrium positions in austenite and residual stresses in the tensile load direction were observed. The results of X-ray diffraction analysis confirmed that the only stress-induced γ→ε-martensite transformation occurred upon deformation (no traces of the γ→α′ one was found). In this case, the volume fraction of ε-martensite was about 2–3%. These transformation-induced plasticity (TRIP) patterns were discussed in terms of changes in the phase composition of steel as the root cause.

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Thermodynamic Behavior of Fe-Mn and Fe-Mn-Ag Powder Mixtures during Selective Laser Melting

Metals ◽

10.3390/met11020234 ◽

2021 ◽

Vol 11 (2) ◽

pp. 234

Author(s):

Jakob Kraner ◽

Jožef Medved ◽

Matjaž Godec ◽

Irena Paulin

Keyword(s):

Selective Laser Melting ◽

Manganese Oxides ◽

Elevated Temperatures ◽

Manganese Content ◽

Chemical Compositions ◽

Metal Powders ◽

Laser Melting ◽

Powder Mixtures ◽

Ε Martensite ◽

The Impact

Additive manufacturing is a form of powder metallurgy, which means the properties of the initial metal powders (chemical composition, powder morphology and size) impact the final properties of the resulting parts. A complete characterization, including thermodynamic effects and the behavior of the metal powders at elevated temperatures, is crucial when planning the manufacturing process. The analysis of the Fe-Mn and Fe-Mn-Ag powder mixtures, made from pure elemental powders, shows a high susceptibility to sintering in the temperature interval from 700 to 1000 °C. Here, numerous changes to the manganese oxides and the αMn to βMn transformation occurred. The problems of mechanically mixed powders, when using selective laser melting, were highlighted by the low flowability, which led to a less controllable process, an uncontrolled arrangement of the powder and a large percentage of burnt manganese. All this was determined from the altered chemical compositions of the produced parts. The impact of the increased manganese content on the decreased probability of the transformation from γ-austenite to ε-martensite was confirmed. The ε-martensite in the microstructure increased the hardness of the material, but at the same time, its magnetic properties reduce the usefulness for medical applications. However, the produced parts had comparable elongations to human bone.

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Mechanical Properties and Microstructural Aspects of Two High-Manganese Steels with TWIP/TRIP Effects: A Comparative Study

Metals ◽

10.3390/met11010024 ◽

2020 ◽

Vol 11 (1) ◽

pp. 24

Author(s):

Matías Bordone ◽

Juan Perez-Ipiña ◽

Raúl Bolmaro ◽

Alfredo Artigas ◽

Alberto Monsalve

Keyword(s):

Mechanical Response ◽

Volume Fraction ◽

Tensile Tests ◽

Optical Microscope ◽

Chemical Compositions ◽

High Manganese ◽

Microstructural Changes ◽

Ε Martensite ◽

High Manganese Steels ◽

Manganese Steels

This article is focused on the mechanical behavior and its relationship with the microstructural changes observed in two high-manganese steels presenting twinning-induced plasticity (TWIP) and transformation-induced plasticity (TRIP), namely Steel B and Steel C, respectively. Chemical compositions were similar in manganese, but carbon content of Steel B approximately doubles Steel C, which directly impacted on the stacking fault energy (SFE), microstructure and mechanical response of each alloy. Characterization of as-cast condition by optical microscope revealed a fully austenitic microstructure in Steel B and a mixed microstructure in Steel C consisting of austenite grains and thermal-induced (εt) martensite platelets. Same phases were observed after the thermo-mechanical treatment and tensile tests, corroborated by means of X-Ray Diffraction (XRD), which confirms no phase transformation in Steel B and TRIP effect in Steel C, due to the strain-induced γFCC→εHCP transformation that results in an increase in the ε-martensite volume fraction. Higher values of ultimate tensile strength, yield stress, ductility and impact toughness were obtained for Steel B. Significant microstructural changes were revealed in tensile specimens as a consequence of the operating hardening mechanisms. Scanning Electron Microscopy (SEM) observations on the tensile and impact test specimens showed differences in fracture micro-mechanisms.

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Determining the Amount of ε-Martensite during Low-Temperature Deformation by a Resistometric Technique

Advances in Cryogenic Engineering Materials ◽

10.1007/978-1-4757-9056-6_21 ◽

1998 ◽

pp. 161-165

Author(s):

M. M. Chernik ◽

L. V. Skibina

Keyword(s):

Low Temperature ◽

Temperature Deformation ◽

Ε Martensite

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Formation, reverse transformation, and properties of ε-martensite phase in the CoCrFeMnNi high-entropy alloy under high-pressure

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2018.11.245 ◽

2019 ◽

Vol 779 ◽

pp. 1-6 ◽

Cited By ~ 7

Author(s):

Pengfei Yu ◽

Lijun Zhang ◽

Hu cheng ◽

Hu Tang ◽

Jiantao Fan ◽

...

Keyword(s):

High Pressure ◽

Martensite Phase ◽

Reverse Transformation ◽

High Entropy Alloy ◽

High Entropy ◽

Ε Martensite

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Effect of Thermomechanical Cycling on Martensitic Transformation and Shape Memory Effect in 304 Austenitic Steel

Metals ◽

10.3390/met10070901 ◽

2020 ◽

Vol 10 (7) ◽

pp. 901

Author(s):

Jie Chen ◽

Yonghao Zhang ◽

Jiqiang Ge ◽

Huabei Peng ◽

Shuke Huang ◽

...

Keyword(s):

Martensitic Transformation ◽

Shape Memory ◽

Austenitic Steel ◽

Shape Memory Effect ◽

Memory Effect ◽

Annealing Temperature ◽

Cycle Number ◽

Thermomechanical Cycling ◽

Ε Martensite ◽

Optimum Annealing Temperature

To improve the shape memory effect (SME) of 304 austenitic steel effectively and efficiently, thermomechanical cycling, comprising deformation at room temperature and annealing, was applied. The influences of cycle number and annealing temperature on the SME and microstructures in 304 austenitic steel were investigated by light microscope (LM), X-ray diffraction (XRD), and transmission electron microscope (TEM). The shape recovery ratio was remarkably improved from 16% to 40% after two thermomechanical cycles. The optimum annealing temperature was 833 K in the process of thermomechanical cycling. The improved SME by thermomechanical cycling was mainly related to stress-induced ε martensite rather than stress-induced α’ martensite. The reason is that thermomechanical cycling can not only promote the occurrence of the stress-induced γ→ε martensitic transformation, but also suppress the subsequently stress-induced ε→α′ transformation.

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Tensile Properties and Damping Capacity of Cold-Rolled Fe-20Mn-12Cr-3Ni-3Si Damping Alloy

Materials ◽

10.3390/ma14205975 ◽

2021 ◽

Vol 14 (20) ◽

pp. 5975

Author(s):

Jae-Hwan Kim ◽

Jong-Min Jung ◽

Hyunbo Shim

Keyword(s):

Tensile Strength ◽

Cold Rolling ◽

Tensile Properties ◽

Volume Fraction ◽

High Strength ◽

Damping Capacity ◽

Austenite Stability ◽

Ε Martensite ◽

Cold Rolled ◽

The Relationship

The tensile properties and damping capacity of cold-rolled Fe–20Mn–12Cr–3Ni–3Si alloys were investigated. The martensitic transformation was identified, including surface relief with a specific orientation and partial intersection. Besides, as the cold rolling degree increased, the volume fraction of ε-martensite increased, whereas α’-martensite started to form at the cold rolling degree of 15% and slightly increased to 6% at the maximum cold rolling degree. This difference may be caused by high austenite stability by adding alloying elements (Mn and Ni). As the cold rolling degree increased, the tensile strength linearly increased, and the elongation decreased due to the fractional increment in the volume of martensite. However, the damping capacity increased until a 30% cold rolling degree was approached, and then decreased. The irregular tendency of the damping capacity was confirmed, depicting that it increased to a specific degree and then decreased as the tensile strength and elongation increased. Concerning the relationship between the tensile properties and the damping capacity, the damping capacity increased and culminated, and then decreased as the tensile properties and elongation increased. The damping capacity in the high-strength area tended to decrease because it is difficult to dissipate vibration energy into thermal energy in alloys with high strength. In the low-strength area, on the other hand, the damping capacity increased as the strength increased since the increased volume fraction of ε-martensite is attributed to the increase in the damping source.

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