Thermal, structural, and microstructural characterization of eutectoid steel at different heat treatments

Investigations of microstructural differences of tempered eutectoid steel strips are presented. The constituent phases – fine mixture of ferrite and cementite and a small amount of retained austenite – considerably affect the mechanical properties, especially the resistance to high cycle fatigue. The amount of retained austenite was determined by XRD and EBSD analysis. Thermoelectric power (TEP) measurements were performed for 270 different batches of C75S type eutectoid steel strips. TEP measurement shows characteristically the fine microstructural differences. The TEP of the investigated samples varied between 5650 and 7030 nV/°C. The amount of retained austenite can be significantly higher at the surface (20 %) than at the internal part (0-5 %). The sensitivity of XRD analysis was reduced because of the presence of coarse cementite particles. Using Cu anode, the measurements were more successful than in case of using Co anode. The EBSD analysis showed that also samples immeasurable with XRD contain retained austenite, but its detectability with XRD analysis declines with the coarsening of cementite.

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On the topological, morphological, and microstructural characterization of nanoporous metals

MRS Bulletin ◽

10.1557/mrs.2017.303 ◽

2018 ◽

Vol 43 (1) ◽

pp. 20-26 ◽

Cited By ~ 29

Author(s):

Erica T. Lilleodden ◽

Peter W. Voorhees

Keyword(s):

Microstructural Characterization ◽

Nanoporous Metals ◽

Image Position

Abstract

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Mechanical and Microstructural Characterization of AF955 (UNS N09955) Nickel-Based Superalloy After Different Heat Treatments

Metallurgical and Materials Transactions A ◽

10.1007/s11661-018-4876-9 ◽

2018 ◽

Vol 49 (11) ◽

pp. 5339-5352 ◽

Cited By ~ 3

Author(s):

Andrea Serafini ◽

Giuliano Angella ◽

Carlo Malara ◽

Maria Francesca Brunella

Keyword(s):

Microstructural Characterization ◽

Heat Treatments ◽

Nickel Based Superalloy

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Microstructural Characterization of Zinc Alloy ZA27 with Modification and Heat Treatments

Proceedings of the 5th International Conference on Information Engineering for Mechanics and Materials ◽

10.2991/icimm-15.2015.53 ◽

2015 ◽

Author(s):

Shuo Zhang ◽

Xiaolin Wei ◽

Wenbin Yu ◽

Zheng Lian ◽

Huaizhi Zhao

Keyword(s):

Microstructural Characterization ◽

Heat Treatments ◽

Zinc Alloy

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Microstructural characterization of CoPtCr/Cr thin film disks by cross-section TEM and elongated probe micro-diffraction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088129 ◽

1991 ◽

Vol 49 ◽

pp. 762-763

Author(s):

M.A. Parker ◽

K.E. Johnson ◽

C. Hwang ◽

A. Bermea

Keyword(s):

Magnetic Recording ◽

Electron Probe ◽

Microstructural Characterization ◽

Crystallographic Structure ◽

Recording Media ◽

Layer By Layer ◽

Cross Sectional ◽

New Techniques ◽

Polished Side

We have reported the dependence of the magnetic and recording properties of CoPtCr recording media on the thickness of the Cr underlayer. It was inferred from XRD data that grain-to-grain epitaxy of the Cr with the CoPtCr was responsible for the interaction observed between these layers. However, no cross-sectional TEM (XTEM) work was performed to confirm this inference. In this paper, we report the application of new techniques for preparing XTEM specimens from actual magnetic recording disks, and for layer-by-layer micro-diffraction with an electron probe elongated parallel to the surface of the deposited structure which elucidate the effect of the crystallographic structure of the Cr on that of the CoPtCr.XTEM specimens were prepared from magnetic recording disks by modifying a technique used to prepare semiconductor specimens. After 3mm disks were prepared per the standard XTEM procedure, these disks were then lapped using a tripod polishing device. A grid with a single 1mmx2mm hole was then glued with M-bond 610 to the polished side of the disk.

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Microstructural Characterization of Au-Ge-Ni based ohmic contacts to GaAs/AlGaAs modfet device

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126433 ◽

1987 ◽

Vol 45 ◽

pp. 326-327

Author(s):

A.K. Rai ◽

A.K. Petford-Long ◽

A. Ezis ◽

D.W. Langer

Keyword(s):

Contact Resistance ◽

Ohmic Contact ◽

Ohmic Contacts ◽

Microstructural Characterization ◽

Almost Everywhere ◽

Spacer Layer ◽

Good Contact ◽

The Relationship ◽

Lower Contact

Considerable amount of work has been done in studying the relationship between the contact resistance and the microstructure of the Au-Ge-Ni based ohmic contacts to n-GaAs. It has been found that the lower contact resistivity is due to the presence of Ge rich and Au free regions (good contact area) in contact with GaAs. Thus in order to obtain an ohmic contact with lower contact resistance one should obtain a uniformly alloyed region of good contact areas almost everywhere. This can possibly be accomplished by utilizing various alloying schemes. In this work microstructural characterization, employing TEM techniques, of the sequentially deposited Au-Ge-Ni based ohmic contact to the MODFET device is presented.The substrate used in the present work consists of 1 μm thick buffer layer of GaAs grown on a semi-insulating GaAs substrate followed by a 25 Å spacer layer of undoped AlGaAs.

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Microstructural characterization of a cast RENi5-based alloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100151714 ◽

1993 ◽

Vol 51 ◽

pp. 1176-1177

Author(s):

G. M. Micha ◽

L. Zhang

Keyword(s):

Electron Microscopy ◽

Rare Earth ◽

Microstructural Characterization ◽

Binary Compound ◽

Nickel Metal ◽

Cast Material ◽

Nickel Metal Hydride ◽

Transmission Electron ◽

Cast Condition

RENi5 (RE: rare earth) based alloys have been extensively evaluated for use as an electrode material for nickel-metal hydride batteries. A variety of alloys have been developed from the prototype intermetallic compound LaNi5. The use of mischmetal as a source of rare earth combined with transition metal and Al substitutions for Ni has caused the evolution of the alloy from a binary compound to one containing eight or more elements. This study evaluated the microstructural features of a complex commercial RENi5 based alloy using scanning and transmission electron microscopy.The alloy was evaluated in the as-cast condition. Its chemistry in at. pct. determined by bulk techniques was 12.1 La, 3.2 Ce, 1.5 Pr, 4.9 Nd, 50.2 Ni, 10.4 Co, 5.3 Mn and 2.0 Al. The as-cast material was of low strength, very brittle and contained a multitude of internal cracks. TEM foils could only be prepared by first embedding pieces of the alloy in epoxy.

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