The Significant Impact of the Characteristics of Granular Structure and Granular Bainite on the Mechanisms Contributing to Strength–Ductility Combination

2021 ◽  
Author(s):  
X. N. Xu ◽  
Y. Tian ◽  
Q. B. Ye ◽  
R. D. K. Misra ◽  
Z. D. Wang
Keyword(s):  
Granular Structure ◽  
Granular Bainite

Triple Fixation For Electron Microscopy

1968 ◽  
Vol 26 ◽  
pp. 90-91 ◽  
Author(s):  
M. A. Hayat
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Electron Beam ◽  
Plasma Membrane ◽  
Myelin Sheath ◽  
Good Deal ◽  
Granular Structure ◽  
Oxidizing Agent ◽  
Fixation Technique ◽  
Large Clusters

Potassium permanganate has been successfully employed to study membranous structures such as endoplasmic reticulum, Golgi, plastids, plasma membrane and myelin sheath. Since KMnO4 is a strong oxidizing agent, deposition of manganese or its oxides account for some of the observed contrast in the lipoprotein membranes, but a good deal of it is due to the removal of background proteins either by dehydration agents or by volatalization under the electron beam. Tissues fixed with KMnO4 exhibit somewhat granular structure because of the deposition of large clusters of stain molecules. The gross arrangement of membranes can also be modified. Since the aim of a good fixation technique is to preserve satisfactorily the cell as a whole and not the best preservation of only a small part of it, a combination of a mixture of glutaraldehyde and acrolein to obtain general preservation and KMnO4 to enhance contrast was employed to fix plant embryos, green algae and fungi.

Granular bainite or granular ferrite? A preliminary TEM investigation of an HSLA-100 steel

1991 ◽  
Vol 49 ◽  
pp. 584-585
Author(s):  
R. Varughese ◽  
S. W. Thompson ◽  
P. R. Howell
Keyword(s):  
Room Temperature ◽  
Transformation Products ◽  
Accurate Description ◽  
Granular Bainite ◽  
Preliminary Results ◽  
The Past ◽  
Light Micrograph ◽  
Multiphase Reaction ◽  
Detailed Nature

Ever since Habraken and Economopoulos first employed the term granular bainite to classify certain unconventional transformation products in continuously cooled steels, the term has been widely accepted and used, despite the lack of a clear consensus as to the detailed nature of the transformation products which constitute granular bainite. This paper presents the preliminary results of a TEM investigation of an 0.04 wt% C, copper-containing steel (designated HSLA-100). It is suggested that the term granular ferrite rather than granular bainite is a more accurate description of this multiphase reaction product.Figure 1 is a light micrograph of a sample which had been air-cooled from 900°C to room temperature. The microstructure is typical of that which has been termed granular bainite in the past and appears to consist of equiaxed ferritic grains together with other minor transformation products. In order to examine these structures in more detail, both continuously cooled and isothermally transformed and quenched materials have been examined with TEM. Granular bainite has been found in virtually all samples.

scholarly journals Continuous Cooling Transformation Diagram, Microstructures, and Properties of the Simulated Coarse-Grain Heat-Affected Zone in a Low-Carbon Bainite E550 Steel

Metals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 939 ◽  
Author(s):  
Yun Zong ◽  
Chun-Ming Liu
Keyword(s):  
Impact Toughness ◽  
Cooling Rate ◽  
Vickers Hardness ◽  
Heat Affected Zone ◽  
Granular Bainite ◽  
Coarse Grain ◽  
Low Carbon ◽  
Transformation Diagram ◽  
Lath Bainite ◽  
Continuous Cooling Transformation Diagram

In order to provide important guidance for controlling and obtaining the optimal microstructures and mechanical properties of a welded joint, the continuous cooling transformation diagram of a new low-carbon Nb-microalloyed bainite E550 steel in a simulated coarse-grain heat-affected zone (CGHAZ) has been constructed by thermal dilatation method in this paper. The welding thermal simulation experiments were conducted on a Gleeble-3800 thermo-mechanical simulator. The corresponding microstructure was observed by a LEICA DM2700M. The Vickers hardness (HV) and the impact toughness at −40 °C were measured according to the ASTM E384 standard and the ASTM E2298 standard, respectively. The experimental results may indicate that the intermediate temperature phase transformation of the whole bainite can occur in a wide range of cooling rates of 2–20 °C/s. In the scope of cooling rates 2–20 °C/s, the microstructure of the heat-affected zone (HAZ) mainly consists of lath bainite and granular bainite. Moreover, the proportion of lath bainite increased and granular bainite decreased as the cooling rate increasing. There is a spot of lath martensite in the microstructure of HAZ when the cooling rate is above 20 °C/s. The Vickers hardness increases gradually with the increasing of the cooling rate, and the maximum hardness is 323 HV10. When the cooling time from 800 °C to 500 °C (t8/5) is 5–15 s, it presents excellent −40 °C impact toughness (273–286 J) of the CGHAZ beyond the base material (163 J).

The tempering behavior of martensite/austenite islands on the mechanical properties of a low alloy Mn-Ni-Mo steel with granular bainite

2021 ◽  
Vol 26 ◽  
pp. 102166
Author(s):  
Zhonghua Jiang ◽  
Yonghan Li ◽  
Zhendan Yang ◽  
Pei Wang ◽  
Dianzhong Li ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Granular Bainite

Supplementary descriptions of Pergalumna amamiensis Aoki, 1984 (Acariformes, Galumnoidea) from Ryukyu Islands

Zootaxa ◽  
2019 ◽  
Vol 4647 (1) ◽  
pp. 378-384
Author(s):  
WATARU HAGINO ◽  
SATOSHI SHIMANO
Keyword(s):  
Body Length ◽  
Morphological Traits ◽  
Granular Structure ◽  
Surface Pattern ◽  
Ryukyu Islands ◽  
Body Width ◽  
Okinawa Island ◽  
Ishigaki Island ◽  
Circular Surface ◽  
Median Pore

A species of oribatid mites, Pergalumna amamiensis was collected from Amami-Ohshima Island, Ishigaki Island, and Okinawa Island, Southwestern Japan. The specimens were studied in detail, and supplementary descriptions are provided; these include features of the rostrum, the subcapitulum and the surface pattern of pteromorphs. The main morphological traits for this species are summarized as follows; body length 519–570 μm, body width 363–410 μm, rostral tip pointed, sensillus with a long stalk covered by minute barbs, porose areas Aa bulbous, porose areas A1, A2, and A3 circular, surface of pteromorphs ornamented by fine granular structure and dense wrinkles, fine granular structure on prodorsum, subcapitulum, genital plates and anal plates, median pore on the notogaster represented as single pore. 

Anisotropy of Mechanical Properties of API-X70 Spiral Welded Pipe Steels

2013 ◽  
Vol 753 ◽  
pp. 538-541 ◽  
Author(s):  
Haytham M. Al Jabr ◽  
John G. Speer ◽  
David K. Matlock ◽  
Peng Zhang ◽  
Sang Hyun Cho
Keyword(s):  
Rolling Direction ◽  
Charpy Impact ◽  
Charpy Impact Test ◽  
Impact Testing ◽  
Granular Bainite ◽  
Secondary Phases ◽  
Pronounced Increase ◽  
Ductile To Brittle Transition ◽  
Welded Pipe ◽  
Anisotropy Of Mechanical Properties

The effects of microstructure and texture on the toughness anisotropy of two API-X70 pipeline steels were investigated. One steel contained no nickel (0Ni) and the other contained 0.3 wt pct nickel (0.3Ni). Charpy V-notch impact testing was conducted on plate samples for both steels in three directions: longitudinal (L), transverse (T), and diagonal (D) with respect to the rolling direction. The microstructures of both steels were mixed and consisted of acicular ferrite, granular bainite, and small amounts of polygonal ferrite, with martensite-austenite and retained austenite islands as secondary phases. The ductile to brittle transition temperatures (DBTT) for the Charpy impact test were higher in the D direction for both plates, with a pronounced increase in the 0Ni steel. The anisotropy in toughness was mainly attributed to the crystallographic texture.

Development of Ge Nanoparticles Embedded in GeO2 Matrix

2008 ◽  
Vol 8 (8) ◽  
pp. 4081-4085 ◽  
Author(s):  
Y. Batra ◽  
D. Kabiraj ◽  
D. Kanjilal
Keyword(s):  
Electron Microscopy ◽  
Annealing Temperature ◽  
Spectroscopic Studies ◽  
Electron Beam Evaporation ◽  
Granular Structure ◽  
Raman Analysis ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Ge Nanocrystals

Germanium (Ge) nanoparticles have attracted a lot of attention due to their excellent optical properties. In this paper, we report on the formation of Ge nanoparticles embedded in GeO2 matrix prepared by electron beam evaporation and subsequent annealing. Transmission electron microscopy (TEM) studies clearly indicate the formation of Ge nanocrystals in the films annealed at 500 °C. Fourier transform infrared (FTIR) spectroscopic studies are carried out to verify the evolution of the structure after annealingat each stage. Micro-Raman analysis also confirms the formation of Ge nanoparticles in the annealed films. Development of Ge nanoparticles is also established by photoluminescence (PL) analysis. Surface morphology study is carried out by atomic force microscopy (AFM). It shows the evolution of granular structure of the films with increasing annealing temperature.

Statistical model of cleavage fracture in granular bainite in simulated weld heat affected zone

1989 ◽  
Vol 5 (9) ◽  
pp. 913-917 ◽  
Author(s):  
X. X. Xu ◽  
Q. G. Cai ◽  
Y. Su ◽  
C. X. Hou ◽  
W. D. Ma
Keyword(s):  
Statistical Model ◽  
Cleavage Fracture ◽  
Heat Affected Zone ◽  
Granular Bainite ◽  
Weld Heat

scholarly journals Finite element simulation of discrete media with granular structure

2002 ◽  
Vol 38 (5) ◽  
pp. 1967-1969 ◽  
Author(s):  
R. Dittrich ◽  
T. Schrefl ◽  
H. Forster ◽  
D. Suess ◽  
W. Scholz ◽  
...  
Keyword(s):  
Finite Element ◽  
Finite Element Simulation ◽  
Granular Structure ◽  
Element Simulation ◽  
Discrete Media

CLAY ILLUVIATION IN SOME ORTHIC PODZOLS OF EASTERN CANADA

1965 ◽  
Vol 45 (2) ◽  
pp. 127-138 ◽  
Author(s):  
J. E. Brydon
Keyword(s):  
Organic Matter ◽  
New Brunswick ◽  
Iron Oxides ◽  
Clay Content ◽  
Granular Structure ◽  
Charge Component ◽  
Eastern Canada ◽  
Free Iron ◽  
Fine Clay ◽  
Ph Dependent

The Arago, Barney, and Holmesville soils, Podzols from Quebec, Nova Scotia, and New Brunswick, respectively, each had friable Bfh horizons with moderate granular structure, and with organic matter and free Fe2O3 contents greater than the Ae and C horizons. The Arago and Holmesville had thin Bhft horizons containing over 10% organic matter and 5% free iron oxides. The C horizons of these two soils had some features characteristic of fragipans.The B horizons of the three soils had a high "pH-dependent charge component" in the C.E.C. values. The "permanent charge component" was similar throughout the Arago profile except for the Bhft horizon where clay accumulation had occurred.Translocation of clay from the Ae to the upper B horizons was indicated by the twofold increase in clay content and the relative enrichment of fine clay in the B horizons. Removal of free iron affected the clay contents differently in the different: horizons but the maximum clay content in the upper B horizons remained. The definitions of Orthic Podzols, Textural Podzols, and t horizons should be re-examined.

Sign in / Sign up

Export Citation Format

Share Document