Wyniki wyszukiwania - Biblioteka Nauki

1

Analiza wpływu parametrów wytwarzania oraz rodzaju zastosowanych proszków elementarnych na strukturę spieków żelazo-mangan-węgiel.

100%

Sułowski M.

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1999

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tom R. 44, nr 10

509-515

PL

Przedstawiony został wpływ punktu rosy atmosfery spiekania, temperatury spiekania, prędkości chłodzenia od temperatury spiekania oraz rodzaju zastosowanych proszków elementarnych jako czynników decydujących o strukturze spiekanych konstrukcyjnych stali manganowych Fe-3 % Mn-0,8 % C oraz Fe-4 % Mn-0,8 % C

EN

The powder metallurgy route may allow sintered manganese steels to be made based on pure iron and ferromanganese powders. The factors that contribute to the structure of sintered Fe-3 % Mn-0,8 % C and Fe-4 % Mn-0,8 % C manganese steel, such as the sintering atmosphere dew point, sintering temperature, cooling rate and powders grade are summarised.

2

Warunki wytwarzania spiekanych konstrukcyjnych stali manganowych. Część I: zagadnienia teoretyczne dotyczące produkcji spiekanych stali manganowych

84%

Sułowski M.

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tom R. 49, nr 12

627-632

PL

W artykule zaprezentowano stan wiedzy dotyczący wytwarzania stali manganowych. Jest on również pierwszą częścią cyklu artykułów dotyczących produkcji konstrukcyjnych spieków żelazo-mangan-węgiel. Autor zwraca w nim szczególną uwagę na zagadnienia teoretyczne związane z układami równowagi fazowej metal-Mn oraz metal-Mn-C, opisując również przemiany fazowe zachodzące w odlewanych, a także w spiekanych stalach manganowych.

EN

The paper presents state-of-the-art in the field of manganese steels fabrication. It is the first from a series of papers related to the production of constructional sinters iron-manganese-carbon. Particular attention was drawn to theoretical issues related to phase equilibrium in the metal-Mn and metal-Mn-C systems. Moreover, phase transformations taking place in manganese steels, cast and sintered, have been described.

3

The Effect of Work Hardening on the Structure and Hardness of Hadfield Steel

84%

Bańkowski D. , Młynarczyk P. , Depczyński W. P. , Bolanowski K.

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tom Vol. 24, iss. 1

14--20

EN

The article aims to characterize Hadfield steel by analyzing its chemical composition, mechanical properties, and microstructure. The study focused on the twinning-induced work hardening of the alloy, which led to an increase in its hardness. The experimental data show that the material hardness at the surface improved considerably after solution heat treatment and work hardening, reaching more than 750 HV. By contrast, the hardness of the material core in the supersaturated condition was about 225 HV. The chemical and phase compositions of the material at the surface were compared with those of the core. The microstructural analysis of the steel revealed characteristic decarburization of the surface layer after solution heat treatment. The article also describes the effects of heat treatment on the properties and microstructure of Hadfield steel. The volumetric (qualitative) analysis of the computed tomography (CT) data of Hadfield steel subjected to heavy dynamic loading helped detect internal flaws, assess the material quality, and potentially prevent the structural failure or damage of the element tested.

4

Rola manganu w spiekanych stalach.

84%

Romański A. , Frydrych H.

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tom R. 43, nr 3

132-139

PL

Na podstawie danych literaturowych przedstawiono przegląd badań nad własnościami spiekanych stali manganowych. Podano również wpływ dodatków stopowych, takich jak miedź, molibden, krzem na zmiany wymiarowe badanych spieków, gęstość, wytrzymałość na rozciąganie, granicę plastyczności, twardość i wydłużenie tych stali.

EN

Based on the review of papers the results of the investigations of sintered manganese steels are presented. The effect of additional alloying elements such as copper, molibdenium and silicon on dimensional changes, density, tensile strength, yield strength, hardness and elongation of such steels are also reported.

5

Contribution to the Modelling of Processes Controlling the Acicular Ferrite (AF) Formation in C-Mn Steels

84%

Mazancová E. , Jonšta Z. , Mazanec K.

Machine Dynamics Problems

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2006

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tom Vol. 30, No. 4

60-67

EN

Due to special morphology, AF microstructure makes possible to obtain a very favourable combination of mechanical properties (strength, ductility and toughness). The significant parameter is the deflection mechanism limiting cleavage crack propagation. Although the nucleation role of fine special non-metallic inclusions as inoculants controlling the austenite (A)-decomposition into ferrite has been described in great number of works, the comprehensive mechanism of these processes has not been developed. Due to large variety of non-metallic particles acting as inoculants in above considered transformation process, this solution is not facile. The nucleation potency of individual phases comprising complex inclusions has not been assessed so far. In the present contribution the investigation will be devoted to the finding of model being able to describe the nucleating behaviour of some complex inclusions based on manganese - silicate (MnO-SiO2) and on the nucleating effect of Mg-addition (MgO) to the basic chemical constitution resulting from deoxidization with Mn/Si/Ti. Among considered mechanism as the most perspective one could be held the formation of Mn-depleted zone being the nucleation site for intragranular A-decomposition into ferrite phase. It has been proposed this zone is formed around inclusion by the subsequent MnS nucleation on it. This process is accompanied with the subsequent Mn-diffusion running in the steel matrix to the MnS-nuclei. The following conclusions can be determined from the achieved results in investigated steel types. The nucleation potency of some inclusions complex represents a decisive initiation parameter in decomposition of A into AF. It has been established the higher density number of dispersed fine intragranular particles (0.5-2.0 µm) is very effective in the refinement of ferrite plates by AF nucleation. The non-metallic inclusions type participating in the considered nucleation process is determined by steel deoxidization. Precipitation of MnS on primary inclusions (investigated influence of Mn/Si and Mn/Si/Ti) has been analyzed. For both examples the same physical metallurgical characteristics leading to the formation of Mn-depleted zone and simultaneously realized MnS nucleation on applied non-metallic inclusions have been found. In case of AF nucleation on inclusions after Mg addition the mechanism of Mn-depleted zone has been also confirmed. The mechanism of AF formation in connection with Mn-depleted zone existence around the primary steel inclusions accompanied with MnS formation has been analyzed in detail. This complex mechanism can be considered as a very attractive model making possible to predict the AF nucleability in austenitic matrix.

6

Properties of Mo-alloyed sintered manganese steels.

59%

Romański A. , Ciaś A.

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tom R. XIX, nr 4

1175-1178

EN

Sintered alloy steels are needed for mostly PM structural parts. Powder metallurgy techniques provide a means of fabricating high quality steel parts with tailored mechanical properties. It is now possible to produce sintered steel parts with properties equal to and even superior to those of parts made by more traditional routes. Challenges arise both with the material selection and component fabrication. This presentation outlines the processing for high performance structural application.

7

Effect processing variables on mechanical properties of sintered manganese steels Fe-3%Mn-0.8%C.

51%

Sułowski M. , Ciaś A.

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tom R. XIX, nr 4

1179-1182

EN

The powder metallurgy route may allow sintered manganese steels to be made based on pure iron powder and ferromanganese powder with control over alloy microstructure. The factors that contribute to the mechanical properties of sintered Fe-3%Mn-0,8%C manganese steel, such as the sintering atmosphere, dew point, sintering temperature, cooling rate are summarized. The paper shows the influence of these parameters on the tensile strength, yield strength, transverse rupture strength, impact strength and hardness. It showed that tensile high strength level higher then those of many present sintered steels can be obtained already in the as-sintered condition.