Acoustoelastic Determination of the Fourth Order ODF Coefficients and Application to R-Value Prediction

1988 ◽  
Vol 142 ◽  
Author(s):  
D. Daniel ◽  
K. Sakata ◽  
J. J. Jonas ◽  
I. Makarow ◽  
J. F. Bussiere
Keyword(s):  
Fourth Order ◽  
Low Carbon Steel ◽  
Expansion Method ◽  
Orientation Distribution ◽  
Rolling Plane ◽  
Low Carbon ◽  
Acoustic Transducers ◽  
Pole Figures ◽  
The Hill ◽  
Good Agreement

AbstractThe fourth order orientation distribution function (ODF) coefficients of textured low carbon steel sheets were determined nondestructively from the anisotropy of the velocity of Lamb (So) and SHO plate waves measured using electromagnetic acoustic transducers (EMATs). The three coefficients (C411, C412, C413) are calculated from five velocity measurements made in three directions in the rolling plane of the sheet using the Hill approximation by an iterative numerical method. The coefficients were also determined from Young's modulus measurements based on a resonance technique and are compared to those obtained ultrasonically. The comparison with coefficients determined from X-ray diffraction pole figures permits adjustment of the C411 coefficient and then very good agreement is obtained. The plastic strain ratios (R-values) of the steel samples are predicted from the adjusted coefficients using a series expansion method based on the Taylor theory of crystal plasticity. These are compared with experimental measurements and again good agreement is displayed.

scholarly journals Determination of the Elastic Tensor of a Textured Low-Carbon Steel

1993 ◽  
Vol 21 (1) ◽  
pp. 3-16 ◽  
Author(s):  
P. Spalthoff ◽  
W. Wunnike ◽  
C. Nauer-Gerhard ◽  
H. J. Bunge ◽  
E. Schneider
Keyword(s):  
Carbon Steel ◽  
Elastic Anisotropy ◽  
Low Carbon Steel ◽  
Elastic Stiffness ◽  
Ultrasonic Pulse ◽  
Grain Structure ◽  
Maximum Deviation ◽  
Low Carbon ◽  
The Hill ◽  
Pulse Echo

The components of the elastic stiffness tensor of hot rolled low-carbon steel were determined using an ultrasonic pulse-echo-method. They were also calculated on the basis of X-ray texture measurements using the Hill approximation. The maximum deviation between experimental and calculated values is 3.5%. An influence of the slightly anisotropic grain structure on the elastic anisotropy could not be seen.

scholarly journals Approximation of the Orientation Distribution of Grains in Polycrystalline Samples by Means of Gaussians

1992 ◽  
Vol 19 (1-2) ◽  
pp. 9-27 ◽  
Author(s):  
D. I. Nikolayev ◽  
T. I. Savyolova ◽  
K. Feldmann
Keyword(s):  
Rolling Texture ◽  
Expansion Method ◽  
Operating Mode ◽  
Orientation Distribution ◽  
New Method ◽  
Gaussian Distributions ◽  
Positivity Condition ◽  
The Central Limit Theorem ◽  
Pole Figures ◽  
Series Expansion Method

The orientation distribution function (ODF) obtained by classical spherical harmonics analysis may be falsified by ghost influences as well as series truncation effects. The ghosts are a consequence of the inversion symmetry of experimental pole figures which leads to the loss of information on the “odd” part of ODF.In the present paper a new method for ODF reproduction is proposed. It is based on the superposition of Gaussian distributions satisfying the central limit theorem in the SO(3)-space as well as the ODF positivity condition. The kind of ODF determination offered here is restricted to the fit of Gaussian parameters and weights with respect to the experimental pole figures. The operating mode of the new method is demonstrated for a rolling texture of copper. The results are compared with the corresponding ones obtained by the series expansion method.

The Corrosion of Carbon Steel and Stainless Steel in Simulated Geothermal Media

1985 ◽  
Vol 38 (8) ◽  
pp. 1133 ◽  
Author(s):  
BG Pound ◽  
MH Abdurrahman ◽  
MP Glucina ◽  
GA Wright ◽  
RM Sharp
Keyword(s):  
Carbon Steel ◽  
Corrosion Rate ◽  
Stainless Steels ◽  
Polarization Resistance ◽  
Iron Sulfide ◽  
Low Carbon Steel ◽  
Passive Films ◽  
Low Carbon ◽  
Corrosion Rates ◽  
Good Agreement

The corrosion rates of low-carbon steel, and 304, 316 and 410/420 stainless steels in simulated geothermal media containing hydrogen sulfide have been measured by means of the polarization resistance technique. Good agreement was found between weight-loss and polarization resistance measurements of the corrosion rate for all the metals tested. Carbon steel formed a non-adherent film of mackinawite (Fe1 + xS). The lack of protection afforded to the steel by the film resulted in an approximately constant corrosion rate. The stainless steels also exhibited corrosion rates that were independent of time. However, the 410 and 420 alloys formed an adherent film consisting mainly of troilite ( FeS ) which provided only limited passivity. In contrast, the 304 and 316 alloys appeared to be essentially protected by a passive film which did not seem to involve an iron sulfide phase. However, all the stainless steels, particularly the 410 and 420 alloys, showed pitting, which indicated that some breakdown of the passive films occurred.

Effect of Strain Path and the Magnitude of Prestrain on the Formability of a Low Carbon Steel: On the Textural and Microtextural Developments

2004 ◽  
Vol 126 (1) ◽  
pp. 53-61 ◽  
Author(s):  
S. K. Yerra ◽  
H. V. Vankudre ◽  
P. P. Date ◽  
I. Samajdar
Keyword(s):  
Carbon Steel ◽  
First Generation ◽  
Biaxial Tension ◽  
True Strain ◽  
Low Carbon Steel ◽  
Orientation Distribution ◽  
Deformation Texture ◽  
Low Carbon ◽  
Normal Anisotropy ◽  
Strain Paths

A low carbon steel (0.07-wt % carbon) sheet metal was deformed in five different strain paths, from equi-biaxial tension to plane strain to near uniaxial tension, by in-plane stretching. Textural developments were characterized by X-ray Orientation Distribution Function (ODFs) and the same were simulated using different Taylor type deformation texture models. A strong difference in bulk texture developments was observed at respective strain paths. The textural differences largely explain the changes observed in normal anisotropy values obtained by mechanical testing. The new deformation texture simulation model, Lamel, was quite successful in predicting quantitatively such textural differences. Microscopically, the significant features of the substructures were “strain localizations”—first generation dense dislocation walls (DDWs) and micro bands (MBs). Both in-grain rotations and estimated stored energies did depend on the relative appearance of such strain localizations. These, on the other hand, were distinctly related to the textural softening or dM/dε, where M and ε are the Taylor factor and true strain, respectively.

The Initial Life and Short Crack Propagation Life for Low Carbon Steel Based on Dislocation Method

2018 ◽  
Vol 1145 ◽  
pp. 1-7
Author(s):  
Yuan Long Yang ◽  
Qing Chun Meng ◽  
Wei Ping Hu
Keyword(s):  
Fatigue Life ◽  
Carbon Steel ◽  
Crack Propagation ◽  
Low Carbon Steel ◽  
Short Crack ◽  
Low Carbon ◽  
Grain Sizes ◽  
Steel Material ◽  
The Relationship ◽  
Good Agreement

In the paper, the relationship between the grain size and fatigue life are studied. To specify the initial and short crack propagation life of low carbon steel material, three methods are used in the simulation. At first, the K. Tanaka’s model is introduced to calculate the fatigue life of a grain. Then, the Voronoi Diagram is used to generate the microstructure of grains. At last, a criteria to specify the short crack is proposed. Based on these methods, the numerical simulation is conducted. With the help of the process, the grain sizes are generated randomly in order to specify how grain sizes effect fatigue life. The computational results are in good agreement with the experimental data. The results show that the randomness of fatigue life is closely related to the randomness of grain sizes.

Microstructure and Oxidation of 55%Al-Zn-Si Hot-Dip Coatings Deposited on Low Carbon Steel at High Temperature

2011 ◽  
Vol 399-401 ◽  
pp. 1998-2003 ◽  
Author(s):  
Biao Zhou ◽  
Feng Jin ◽  
Qun Luo ◽  
Qian Li ◽  
Kuo Chih Chou
Keyword(s):  
High Temperature ◽  
High Temperature Oxidation ◽  
Diffusion Rate ◽  
Intermetallic Layer ◽  
Low Carbon Steel ◽  
Low Carbon ◽  
X Ray Diffraction ◽  
Temperature Oxidation ◽  
X Ray ◽  
Good Agreement

The high temperature oxidation and microstructure evolution of 55%Al-Zn-Si coated sheets were studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD). After oxidation, the coatings consisted of three phases including ZnO, Fe2Al5, and FeAl from topcoat to the substrate. The different diffusion rate of Fe and Al result in forming voids at the interface of intermetallic layer and the substrate. A good agreement has been reached between the experimental data and the calculation from Chou diffusion model, which has a good predicted function. Moreover, the characteristic oxidation time and the apparent activation energy were obtained.

scholarly journals An Investigation Into the Accuracy of the Vector Method by Comparison With ECP Measurements

1989 ◽  
Vol 10 (2) ◽  
pp. 117-134 ◽  
Author(s):  
R. Shimizu ◽  
J. Harase ◽  
K. Ohta
Keyword(s):  
Pole Figure ◽  
Direct Measurement ◽  
Orientation Distribution ◽  
Vector Method ◽  
Inversion Result ◽  
X Ray ◽  
Pole Figures ◽  
The Mean ◽  
Actual Orientation ◽  
Good Agreement

In an attempt to investigate the accuracy of the vector method for crystal texture analysis, a comparison has been made between the inversion result of the pole figure made by X-ray studies using the VM and the inversion result of the pole figure made by ECP. A comparison has been made between the inversion by the pole figure generated by direct measurement of orientations by ECP and the actual orientation distribution (measured by ECP) displayed in the same mode. The materials studied were recrystallized Fe–3% Si and Fe–50% Ni. The main findings were:• In the mean intensities of each individual Box, the inversion results of pole figures made from orientations determined by ECP were in good agreement with the inversion from (100) pole figures made by X-ray or actual orientation distribution (made by ECP) displayed in the same mode as the vector method.• For Fe–3% Si, quite a good agreement was obtained between the results inverted from X-ray pole figure and the direct measurement by ECP for the intensity distribution of minor texture component along ζ angle. It was concluded from these investigations that the inversion of the pole figure by the vector method is accurate enough for most practical purposes.

scholarly journals Effects of Double Reduction and Annealing on the Texture during Continuous Rolling of Ultrathin Sheets of Low Carbon Steels

2019 ◽  
Author(s):  
Laura G. Castruita-Avila ◽  
Francisco A. García-Pastor ◽  
Manuel de J. Castro-Roman ◽  
Jesus Emilio Camporredondo-Saucedo ◽  
Fabián Equihua-Guillen ◽  
...  
Keyword(s):  
Texture Evolution ◽  
Low Carbon Steel ◽  
Rolling Process ◽  
Carbon Steels ◽  
Low Carbon ◽  
Double Reduction ◽  
Process Stage ◽  
Texture Intensity ◽  
Pole Figures ◽  
Ebsd Technique

In this paper were analyzed the effects of double reduction and annealing during rolling process on texture evolution in an ultrathin sheet of low carbon steel. Experimental samples were obtained from each process stage. EBSD technique and correlated tools as orientation density functions and pole figures were used to analyze the microstructural changes and the texture. Results show that {111} recrystallized grains were formed during process, reducing dramatically gamma-fibre texture intensity and generating an adequate finished product for deep die stamping.

The iterative series-expansion method for quantitative texture analysis. II. Applications

1992 ◽  
Vol 25 (2) ◽  
pp. 259-267 ◽  
Author(s):  
M. Dahms
Keyword(s):  
Distribution Function ◽  
Series Expansion ◽  
Expansion Method ◽  
Orientation Distribution ◽  
Polycrystalline Materials ◽  
Pole Density ◽  
General Outline ◽  
Positivity Condition ◽  
Pole Figures ◽  
Series Expansion Method

The orientation distribution function (ODF) of the crystallites of polycrystalline materials can be calculated from experimentally measured pole density functions (pole figures). This procedure, called pole-figure inversion, can be achieved by the series-expansion method (harmonic method). As a consequence of the (hkl)-({\bar h}{\bar k}{\bar l}) superposition, the solution is mathematically not unique. There is a range of possible solutions (the kernel) that is only limited by the positivity condition of the distribution function. The complete distribution function f(g) can be split into two parts, \tilde {f}(g) and \tildes {f}(q), expressed by even- and odd-order terms of the series expansions. For the calculation of the even part \tilde {f}(g), the positivity condition for all pole figures contributes essentially to an `economic' calculation of this part, whereas, for the odd part, the positivity condition of the ODF is the essential basis. Both of these positivity conditions can be easily incorporated in the series-expansion method by using several iterative cycles. This method proves to be particularly versatile since it makes use of the orthogonality and positivity at the same time. In the previous paper in this series [Dahms & Bunge (1989) J. Appl. Cryst. 22, 439–447] a general outline of the method was given. This, the second part, gives details of the system of programs used as well as typical examples showing the versatility of the method.

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