scholarly journals Multi-scale phase analyses of strain-induced martensite in austempered ductile iron (ADI) using neutron diffraction and transmission techniques

2020 ◽  
Vol 56 (8) ◽  
pp. 5296-5306
Author(s):  
Xiaohu Li ◽  
Sergio Soria ◽  
Weimin Gan ◽  
Michael Hofmann ◽  
Michael Schulz ◽  
...  
Keyword(s):  
Neutron Diffraction ◽  
Pole Figure ◽  
Ductile Iron ◽  
Imaging Techniques ◽  
Austempered Ductile Iron ◽  
Quantitative Phase Analysis ◽  
Strain Induced Martensite ◽  
Phase Quantification ◽  
Pole Figure Data ◽  
Multi Phase

AbstractThe content of strain-induced martensite in austempered ductile iron has been quantitatively determined using three different kinds of neutron methods: (1) high-resolution powder diffraction with subsequent standard Rietveld refinement, (2) phase quantification using pole figure measurements and (3) Bragg edge neutron transmission. The accuracy and scope of applications of these neutron diffraction and imaging techniques for phase quantification have been compared and discussed in detail. Combination of these methods has been confirmed as effective for dealing with problems like peak overlap in multi-phase materials and texture formation after plastic deformation. Further, the results highlight the potential of using single peak pole figure data for quantitative phase analysis with high accuracy.

scholarly journals Phase Transition Kinetics in Austempered Ductile Iron (ADI) with Regard to Mo Content

Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5266
Author(s):  
Martin Landesberger ◽  
Robert Koos ◽  
Michael Hofmann ◽  
Xiaohu Li ◽  
Torben Boll ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Phase Transformation ◽  
Neutron Diffraction ◽  
Ductile Iron ◽  
Retained Austenite ◽  
Length Change ◽  
Atom Probe ◽  
Carbon Accumulation ◽  
Austempered Ductile Iron ◽  
Mo Content

The phase transformation to ausferrite during austempered ductile iron (ADI) heat treatment can be significantly influenced by the alloying element Mo. Utilizing neutron diffraction, the phase transformation from austenite to ausferrite was monitored in-situ during the heat treatment. In addition to the phase volume fractions, the carbon enrichment of retained austenite was investigated. The results from neutron diffraction were compared to the macroscopic length change from dilatometer measurements. They show that the dilatometer data are only of limited use for the investigation of ausferrite formation. However, they allow deriving the time of maximum carbon accumulation in the retained austenite. In addition, the transformation of austenite during ausferritization was investigated using metallographic methods. Finally, the distribution of the alloying elements in the vicinity of the austenite/ferrite interface zone was shown by atom probe tomography (APT) measurements. C and Mn were enriched within the interface, while Si concentration was reduced. The Mo concentration in ferrite, interface and austentite stayed at the same level. The delay of austenite decay during Stage II reaction caused by Mo was studied in detail at 400 °C for the initial material as well as for 0.25 mass % and 0.50 mass % Mo additions.

In Situ Studies of Intercritically Austempered Ductile Iron Using Neutron Diffraction

2011 ◽  
Vol 43 (5) ◽  
pp. 1468-1476 ◽  
Author(s):  
Alan P. Druschitz ◽  
Ricardo E. Aristizabal ◽  
Edward Druschitz ◽  
C. R. Hubbard ◽  
Thomas R. Watkins ◽  
...  
Keyword(s):  
Neutron Diffraction ◽  
Ductile Iron ◽  
Austempered Ductile Iron ◽  
In Situ Studies

Quantitative Phase Analysis of the Multi-Phase Alloys Using Neutron Diffraction

2004 ◽  
Vol 270-273 ◽  
pp. 1285-1290
Author(s):  
Eun Joo Shin ◽  
Baek Seok Seong ◽  
Tae Won Joung ◽  
Kwang Pyo Hong ◽  
Chang Hee Lee ◽  
...  
Keyword(s):  
Neutron Diffraction ◽  
Phase Analysis ◽  
Quantitative Phase Analysis ◽  
Quantitative Phase ◽  
Multi Phase

scholarly journals Evaluation of Volume Fraction of Austenite in Austempering Process of Austempered Ductile Iron

Metals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 893 ◽  
Author(s):  
Edward Tyrała ◽  
Marcin Górny ◽  
Magdalena Kawalec ◽  
Anna Muszyńska ◽  
Hugo F. Lopez
Keyword(s):  
Ductile Iron ◽  
Volume Fraction ◽  
Metallic Matrix ◽  
Experimental Tests ◽  
Austempered Ductile Iron ◽  
Magnetic Method ◽  
Quantitative Phase Analysis ◽  
Carbide Phases ◽  
Second Stage ◽  
Third Stage

In the present work, an evaluation of the volume fraction of austenite in austempered ductile iron (ADI) is presented by means of three different methods. Experimental tests were conducted on ADI samples after different austempering conditions and contained different volume fractions of the phase components in the metallic matrix (ferrite plates + austenite). A comparison of the volume fraction of austenite was carried out by metallographic magnetic methods using a variable field, as well as X-ray quantitative phase analysis. The main purpose of this work is to show the effectiveness of the proposed magnetic method for estimating the volume fraction of austenite in ADI cast iron. It is evident that the new method in which variable magnetic fields are used to quantify the phase composition exhibits very high accuracy within the second stage of the austempering transformation, in which the metallic matrix consists of ferrite plates and high-carbon austenite. Finally, this research shows that within the first and third stages the estimation of the volume fraction of the austenite is hampered by errors resulting from the presence of martensite (first stage) and carbide phases (third stage).

Neutron diffraction study of austempered ductile iron

1996 ◽  
Vol 27 (4) ◽  
pp. 923-928 ◽  
Author(s):  
C. S. Choi ◽  
W. Sharpe ◽  
J. Barker ◽  
R. J. Fields
Keyword(s):  
Neutron Diffraction ◽  
Diffraction Study ◽  
Ductile Iron ◽  
Neutron Diffraction Study ◽  
Austempered Ductile Iron

Digital imaging and quantitative image analysis of polymer blends

1996 ◽  
Vol 54 ◽  
pp. 170-171
Author(s):  
Xiao Zhang
Keyword(s):  
Digital Imaging ◽  
Imaging Techniques ◽  
Imaging Systems ◽  
Polymer Science ◽  
Key Factors ◽  
Multiple Imaging ◽  
Quantitative Image ◽  
Digital Imaging Systems ◽  
Multi Phase ◽  
Network Technologies

Polymer microscopy involves multiple imaging techniques. Speed, simplicity, and productivity are key factors in running an industrial polymer microscopy lab. In polymer science, the morphology of a multi-phase blend is often the link between process and properties. The extent to which the researcher can quantify the morphology determines the strength of the link. To aid the polymer microscopist in these tasks, digital imaging systems are becoming more prevalent. Advances in computers, digital imaging hardware and software, and network technologies have made it possible to implement digital imaging systems in industrial microscopy labs.

Production of austempered ductile iron gears for transmission cases

2005 ◽  
Vol 47 (9) ◽  
pp. 523-528 ◽  
Author(s):  
Ahmet Sagin ◽  
Ahmet Topuz
Keyword(s):  
Ductile Iron ◽  
Austempered Ductile Iron
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