| Title |
Pesearch Paper / Mechanical Behavior : The Effects of the Local Fracture Stress and Carbides on the Cleavage Fracture Characteristics of Mn-Mo-Ni Low Alloy Steels in the Transition Region |
| Authors |
양원준(Won Jon Yang),허무영(Moo Young Huh),노성주(Sung Joo Roh),이봉상(Bong Sang Lee),오용준(Yong Jun Oh),홍준화(Jun Hwa Hong) |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Abstract |
In the ductile-brittle transition temperature region of SA508 Cl.3 Mn-Mo-Ni low alloy steels, the relationship of the local fracture stress and carbides influencing the cleavage fracture behavior was investigated. Based on the ASTM E1921-97 standard method, the reference transition temperatures were determined by three point bending fracture toughness tests. A local fracture stress, σ^*_f, was determined from a theoretical stress distribution in front of crack tip using the cleavage initiation distance measured in each fractured specimen surface. The local fracture stress values showed a strong relationship with toughness characteristics of the materials and those were larger in the materials of smaller carbide size. Quantitative analysis of carbides showed that carbides larger than a certain size are mainly responsible for the cleavage fracture in the ductile-brittle transition temperature region. |