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Showing 1 to 20 of 34 for “"retained austenite"”.
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Some factors affecting retained austenite in alloy steels
Thesis (M.S.)--Michigan State College of Agriclture and Applied Science. Dept. of Chemical and Metallurgical Enineering, 1947
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Theory and significance of retained austenite in steels
… leading to the retention of small quantities of austenite following the bainite and martensite phase transformations have been examined, together with the influence of retained austenite on the properties of low alloy steels. It was found that the upper and lower bainite transformations are …
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An x-ray spectrometer determination of retained austenite in steel
Thesis (M.S.) Massachusetts Institute of Technology. Dept. of Metallurgy, 1952
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Understanding the Stability of Retained Austenite in High-Carbon Steels: Modelling and Alloy Design
In high-carbon steels, the austenite-to-martensite transformation under applied stress initiates at a critical value, contrary to low-carbon steels where the transformation occurs at the early stages of deformation. There are few models that account for the delayed transformation, because previous …
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ADVANCED HIGH STRENGTH STEEL THROUGH PARAEQUILIBRIUM CARBON PARTITIONING AND AUSTENITE STABILIZATION
More than 30 vol. pct. retained austenite was obtained in quenched and partitioned (QP) 0.3C-4.0Mn steels subjected to dual stabilization heat treatments (DSHT). The temperature of the second quench in the DSHT process successfully played an essential role in the retained austenite contents at …
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An investigation into the mechanisms of cone bore growth in railroad bearings
… studies of (1) stress-induced transformation of retained austenite to martensite, (2) thermal-induced transformation of retained austenite to bainite, and (3) low temperature creep have been conducted. Both carburized and uncarburized 4320 steels were tested. The retained austenite contents …
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Transformations in TRIP-assisted Steels: Microstructure and Properties
… of these steels are due to the transformation of retained austenite into martensite during deformation and hence appear to be dominated by the volume fraction and carbon content of retained austenite. These parameters have been related to the chemical composition and heat treatment of the steels …
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Hydrogen embrittlement resistance in advanced high strength: vanadium bearing and TRIP-assisted steels
… hydrogen desorption which occurs when retained austenite transforms into martensite. This mechanism can be investigated through studying the HE susceptibility of transformation induced plasticity (TRIP) steels. An intensive study was carried out to optimise the TRIP steel heat treatment …
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Carbide-free bainitic steels for wear and rolling contact fatigue resistant applications
… has yet to be found. It is believed that the retained austenite fraction, size and morphology are closely related to its mechanical stability, which is crucial in affecting its transformation to martensite. To investigate the evolution of the microstructure, multiple tests were conducted on a …
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Relationship between Microstructure, Properties and HICC Resistance of HSLA steel weld metals
… as non metallic inclusions (NMI) and martensite-austenitecarbide constituent (MAC), were studied in some detail due to their hydrogen trapping capacity. Fractographic studies of hydrogen charged tensile samples were carried out to study the effect of microstructure and hydrogen content on the …
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Fatigue in low pressure carbonitrided steels
… for the four alloys. The profiles for hardness, retained austenite, residual stress, carbon and nitrogen were comparable for all the alloys. However, the fatigue performance of each alloy was different. The highest endurance limit was attained by 20MnCr5+B, followed by 20MnCr5, SAE 8620+Nb, and …
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Nanostructural Evolution of Hard Turning Layers in Carburized Steel
… microstructures were introduced by altering the retained austenite content. The strain, strain rate and temperature achieved during final metal cutting were altered by varying insert geometry, insert wear and cutting speed. The subsurface evolution was quantified by a series of advanced …
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Effects of deformation modes on the susceptibility of delayed fracture of advanced high strength steels
… and bending deformation. The TRIP780 had some retained austenite after deformation, whereas the TRIP980 showed no evidence of retained austenite after deformation.
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The influence of nickel-nitrogen ratio on the deformation behaviour of austenitic stainless steels
… are that nitrogen is fully dissolved. The austenite stability of the alloys however, varies at room temperature. Alloys containing approximately 5 wt% nickel, with a maximum nitrogen content of 0.28 wt%, contain up to 97% retained austenite, whereas alloys with 3.4 wt% nickel and the same …
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Experimental characterization and modeling of the plastic behavior of a thirdgeneration advanced high strength steel sheet
… composed of martensite, ferrite, and retained austenite. In the asreceived condition, the Xray diffraction analysis provided 12.2% of the retained austenite volume fraction. In the sheet rolling direction, the average values of the yield stress (𝑆𝑦) and ultimate tensile strength (𝑆𝑢) …
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The abrasive wear resistance of austempered spheroidal graphite irons
… constitution of the resulting dual phase ferrite/austenite structure has been examined using optical and scanning electron microscopy and x-ray analysis. The maximum quantity of retained austenite in the structure has been shown to vary up to 50% and to be strongly dependent on heat treatment …
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Modelling of Microstructure Development in Silicon-containing Bainitic Free-machining Steels
… cooling conditions. A model for estimating retained austenite size distribution in the carbide-free bainitic microstructure has been developed. Manganese sulphide particles are used in the free-machining steel to break chips during machining; its effect on the prior austenite grain size has …
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A study of the microstructural basis for the strength and toughness properties of overaged HSLA-100 steel
… bainite/martensite laths and a small amount of retained austenite. The strength and toughness in this specimen was based on the small transformation product packets with their fine laths and highly dislocated substructures. The best combination of strength and toughness occurred for the sample …
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Microscopic Strain Localization and Damage in Multi-phase Alloys
… (QP) steel. Our in situ tracking of metastable retained austenite unravels strong influences of neighborhood microstructure on its mechanical stability and also post-transformation behaviors. Based on our findings, micromechanically-guided microstructure design strategies to better optimize …
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