B. Yordanov
327
Journal of the University of Chemical Technology and Metallurgy, 47, 3, 2012, 327-332
MICROSTRUCTURAL CHARACTERISATION OF 1.2080 STEEL MODIFIED WITHNANO-DISPERSED Si3N4 PARTICLES AFTER VARIOUS HEAT TREATMENTS
B. Yordanov
University of Chemical Technology and Metallurgy8 Kl. Ohridski, 1756 Sofia, BulgariaE-mail: [email protected]
ABSTRACT
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Received 12 March 2012Accepted 12 May 2012
INTRODUCTION
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RESULTS AND DISCUSSION
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Fig. 1. Shape and dimensions of the cast ingots.
Fig. 2. Shape and dimensions of the cut samples.
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Fig. 3. Heat treatment of 1.2080 steel.
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Fig. 4. As-cast microstructure of sample 1: Primary dendritesfrom transformed alloyed austenite (white zones) andledeburite eutectic are (dark zones). Optical micrograph ofan etched sample, at magnification 100x.
Fig. 5. As-cast microstructure of sample 2. Optical micrographof an etched sample, at magnification 100x.
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Journal of the University of Chemical Technology and Metallurgy, 47, 3, 2012
330
Fig. 6. Microstructure of sample 3 without addition of Si3N4 after 35 % deformation and annealing at 870C for 180 min.Optical micrograph of an etched sample at magnification 160x (a) and 800x (b).
Fig. 7. Microstructure of sample 4 with Si3N4 addition after 35 % plastic deformation and annealing at 870C for 180 min.Optical micrograph of an etched sample at magnification of 160x (a) and 400x (b).
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