engleski

The casting powder FT2

During ingot casting for the production of seamless tubes surface with casted powder some surface defect were noted. Defect often transfers to tubes causing the appearance of cracks during the production and/ or use. For determination the cause the phase composition casting powder before and during its successive heating up to 1200°C were observed. Also, refractoriness, sludges, macro and micro inclusion produced during the casting were observed. For investigation samples were taken directly in powdered form or mechanically in the place of overflow of ingot, tubes or immersed tundish. Diffraction patterns of prepared samples were recorded photographically with PW 1024 Debye Scherrer camera (x – ray tube, cobalt 10 mA/ 25 KV, 2 hours), secondary electron micrographs and emitted characteristics x – rays. The results of investigation of cause of surface defects show that they are result of the erosion of chamotte in the channels and tundish immersed and casting powder which only partial converges of the surface of the themelt.

seamless tubes, casting powder, x - ray diffraction, electron micrographs, inclusion, erosion

nije evidentirano