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1

Influence of Particle Size and Load on Loss of Material in Manganese-Steel Material: an Experimental Investigation

Sinha R., Mukhopadhyay A. K.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 1

359--364

EN

The present study explores the influence of variables like particle size of coal, load, speed and sliding distance on weight loss in manganese-steel (Mn-steel). The observations are made using pin-on-disc apparatus. Specimen prepared from Mn-steel used for the wear test. The size and shape of specimen is in accordance with ASTM G99 standard. From design of experiment (DOE) procedure the variables load were altered to assess the weight loss in material. It is observed that with the increase in particle size and load, the weight loss increases when other variables are constant. Mn-steel shows decrease in weight loss at higher load due to property of dipole interaction and stacking fault energy (SFE). Decrease in weight loss at higher load results in transition in wear mechanism from scratch to groove formation as observed under field emission scanning electron microscope (FESEM).

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Energia błędu ułożenia a mechaniczne bliźniakowanie na przykładzie wysokomanganowej stali X30MnAlSi26-4-3

Śmiglewicz A., Jabłońska M., Rodak K.

Hutnik, Wiadomości Hutnicze

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2015

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Vol. 82, nr 8

472--474

PL

W pracy przedstawiono wyniki obliczeń wartości energii błędu ułożenia wysokomanganowej stali X30MnAlSi26-4-3 na podstawie składu chemicznego z wykorzystaniem modelu termodynamicznego zaproponowanego przez G.B. Olson, M. Cohen [1]. Przedstawiono procedurę obliczeniową opartą na modyfikacji wartości ÄGg →ε − molowej energii swobodnej między g i ε, zaproponowaną przez Frommayera [2]. Modyfikacja uwzględnia parametry termodynamiczne określone dla głównych pierwiastków stopowych, tj. C, Mn, Al oraz Si. Wybór zastosowanej metody podyktowany był składem chemicznym badanej stali X30MnAlSi26-4-3. Wyznaczona wartość EBU wskazuje, że badana stal powinna wykazywać skłonność do tworzenia mechanicznych bliźniaków indukowanych odkształceniem plastycznym. Występowanie bliźniaków odkształcenia ujawniono w materiale poddanym próbom dynamicznego odkształcania z zastosowaniem różnej prędkości odkształcenia. Badania strukturalne wykonano z wykorzystaniem techniki skaningowej transmisyjnej mikroskopii elektronowej.

EN

The stacking fault energy of the X30MnAlSi26-4-3 steel was evaluated by analytical method based on chemical composition using a thermodynamic model proposed by Olson G. B., Cohen M. [1]. The paper presents the calculation procedure is based on the modification of the value − the molar free energy between the g and ε proposed by Frommayer [2]. The modification takes into account the thermodynamic parameters determined for the major alloying elements, ie. C, Mn, Al and Si. The choice of the method used was dictated by the investigated steel chemical composition X30MnAlSi26-4-3. The designated value of the SFE indicates that the steel should have a tendency to form mechanical twins induced. The occurrence of deformation twins are disclosed in the material subjected to dynamic deformation tests with the use of a different strain rate. Structural studies were performed using the technique of scanning transmission electron microscopy.

3

Structural and mechanical properties of laboratory rolled steels high-alloyed with manganese and aluminium

Kuc D., Hadasik E., Niewielski G., Schindler I., Mazancova E., Rusz S., Kawulok P.

Archives of Civil and Mechanical Engineering

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2012

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Vol. 12, no. 3

312--317

EN

The paper deals with rolling conditions, microstructure, as well as basic mechanical properties of four different high manganese steels after laboratory melting, casting, and hot and cold rolling. The stacking fault energy of heats was in the interval of 85–114 mJ m−2 thanks to the high aluminium contents. The heats with the lowest sum of (C+Mn) supported the highest ferrite volume fraction (up to 45%), while the highest sum of (C+Mn) led to 10% ferrite formation. With lower Al/(C+Mn) ratio and lower ferrite fraction higher rolling forces were necessary to be used. Due to heterogeneities of matrixes and observed aluminium oxide complexes differences in mechanical properties were detected. The best results showed the heat with 0.65% C−29.5% Mn−9.0% Al and a stacking fault energy 114 mJ m−2.

4

Comparison of microfractographic behaviour of acicular ferrite and bainite and hydrogen cracking resistance

Mazancova E., Jonsta Z., Mazanec K.

Archives of Materials Science

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2007

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Vol. 28, nr 1-4

90-94

EN

Materials characterized as TRIPLEX having decreased density are constituted on the following chemical composition usually: Fe-26/30Al-0.9/1.2C. Alloy microstructure is preferentially based on the FCC arrangement. Further, microstructure consists of nano-size carbides regularly dispersed in the FCC matrix and of low ferritic particle content (8% approximately). The strength level of this material is immediately connected with the solid solution strengthening forming the matrix basis. Besides this effect, it is useful to take into consideration process of its strengthening due to precipitated fine carbides (above mentioned nano-size k-carbides). The preferential effect of this material is connected with its high absorption capacity (double capacity in comparison with the conventional deep drawing steels applied in automotive industry). The formation of uniformly arranged shear bands (SIP effect) has very important influence on the realized deformation process of discussed material and the achieved beneficial technical response. This process is also influenced due to regular distribution of nano-size k-carbides being coherent to the FCC matrix. Owing to the density decrease up to 10-12%, attained strength level (1000 MPa), excellent formability and high resistance to dynamic loading (high absorption and achieved dynamic capacity) the presented high manganese material can be held for perspective type for many applications in automotive industry. Further, this material finds a perspective application in cryogenic technique (transport and storage of liquid gases) and in rotating machine elements, too.

5

Błędy ułożenia - czym są i od czego zależy ich energia.

Wróbel M.

Inżynieria Materiałowa

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2001

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R. XXII, nr 6

1024-1032

PL

W pracy przedstawiono definicje błędów ułożenia (BU) i energii błędu ułożenia, rozróżniając energię hipotetycznego (nieograniczenie rozciągłego) błędu ułożenia, na który nie wpływają dyslokacje (EBU) od energii błędu ułożenia ograniczonego dyslokacjami częściowymi (efektywna energia błędu ułożenia EEBU). Przedyskutowano również ograniczenia traktowania energii błędu ułożenia jako miary względnej stabilności struktur krystalicznych. Krótko przedstawiono podstawy związku EBU z oddziaływaniami atomów i elektronów oraz przedyskutowano przyczyny wyznaczonych zależności EBU od składu chemicznego stopów i od temperatury.

EN

The concept of the stacking faults (SF), the stacking energy (SFE) and selected examples of typical SFs in the face-centered cubic (fcc) structure and in the hexagonal close-packed (hcp) structure is presented. The sequence of stacking and SFs have been described by some letters which designate position of the successive atomic planes. Additionally, Frank notation system as well as notation introduced by Jagodziński were explained and used. Some experimental SFE values for selelcted metals are collected.