The combined effects of the reduction ratio and annealing conditions during cold rolling were investigated for the texture and anisotropy of an EN AW-8011A aluminium alloy. To characterize the ...microstructural and textural differences, a scanning electron microscope with electron back-scattered diffraction was used. To achieve low anisotropy, the three key factors of texture were exposed: a low fraction of deformed grains according to the average grain misorientation, a large amount of random texture components and the equivalent ratio between deformed and recrystallised texture components. The results of crystallographic texture analysis and anisotropy values revealed that the higher ratio of total cold deformation (cold rolling reduction) and the higher ratio of cold deformation after the intermediate annealing were more favourable for the final continuous annealing in terms of decreasing anisotropy. In contrast, the lower ratio of the cold deformation resulted in lower anisotropy when implementing batch annealing.
Annealing of deformed martensite (high-temperature tempering) in St37 steel was studied. Different reductions in thickness were considered and compared with the behavior of as-quenched martensite ...during tempering. tempering of the asquenched martensite was accompanied by the formation of carbide particles, incomplete disappearance of the lath martensite morphology, and continuous decrease in hardness until reaching low values. However, during tempering of the cold rolled martensite, the precipitation of carbides in the lamellar structure, development of distinct equiaxed ultrafine grains through a continuous recrystallization mechanism, and a sudden hardness drop were characterized. The importance of cold rolling reduction and its amount were also discussed.
nema
U radu je prikazana metoda procjene površine ploče formirane uzdužnim hladnim valjanjem, obavljenim pomoću valjaoničkog stana 210 DUO SVa. Izvedeni su pokusi na uzorcima niskougljičnih ...konstrukcijskih čelika, kako bi se utvrdio utjecaj dimenzije zrna materijala s obzirom na tehnološke parametre, a posebice s obzirom na redukciju valjanja i silu valjanja. Hrapavost površine ploča mjerena je na tri mjesta optičkim profilometrom MicroProf FRT. Zbog toga su ovi rezultati međusobno uspoređeni.
U radu su dana rješenja za proračun visine sloja maziva na ulaznom presjeku zone deformacije u ovisnosti o poprečnoj hrapavosti valjaka i uzdužne trake. Analitička rješenja koja prekrivaju područja ...svih zahvatnih kutova hladnog valjanja, uzimaju u obzir i utjecaj visine sloja maziva na traci ispred valjaka. Dana su i objašnjenja kako izvršiti proračun visine sloja maziva kada se hrapavost može zanemariti, tj. kada se približava idealno glatkim površinama, i kada se može zanemariti utjecaj visine sloja maziva na traci ispred valjaka. Rješenja koja vrijede za laminarni tok maziva i izotermne uvjete procesa hladnog valjanja s mazivima, koliko se može vidjeti u podacima literature su jedinstvena.
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