탄소함량이다른경량철강판의냉간압연에의한파괴기구

• Published in: 대한금속재료학회지 Vol. 48; no. 5; pp. 377 - 386
• Main Authors: 한승엽, Seung Youb Han, 신상용, Sang Yong Shin, 이성학, Sung Hak Lee, 김낙준, Nack J. Kim, 곽재현, Jai Hyun Kwak, 진광근, Kwang Geun Chin
• Format: Journal Article
• Language: Korean
• Published: 대한금속재료학회 20.05.2010
• Subjects: fracture; metals; rolling; scanning electron microscopy; SEM; κ-carbide
• ISSN: 1738-8228

An investigation was conducted into the effects of κ-carbides on the cracking phenomenon, which often occurred in cold-rolled light-weight steel plates. Three kinds of steels were fabricated by varying the C content, and their microstructures and tensile properties were investigated. In the two steels that contained a high carbon content, the band structures of ferrites and κ-carbides that were severely elongated along the rolling direction were well developed, whereas continuous arrays of κ-carbides were formed in the steel that contained a low carbon content. Detailed microstructural analyses of the deformed region beneath the tensile fracture surface showed that the cracks initiated at arrays of κ-carbides or κ-carbides formed interfaces between the band structures, which initiated cleavage fractures in the ferrite bands, while the bands populated with a number of κ-carbides did not play an important role in propagating the cracks. Thus, the minimization of interfacial κ-carbides or κ-carbide arrays by increasing the carbon content was essential for preventing cracking from occurring during cold rolling.