Fracture Behavior in α-Ferrite Containing Al

• Published in: Scripta materialia Vol. 38; no. 7; pp. 1077 - 1081
• Main Authors: Heo, N.H., Park, C.H., Na, J.G.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Ltd 03-03-1998; Elsevier Science
• Subjects: Applied sciences; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Fatigue, corrosion fatigue, embrittlement, cracking, fracture and failure; Fatigue, embrittlement, and fracture; Materials science; Metals. Metallurgy; Physics; Treatment of materials and its effects on microstructure and properties; Fracture mechanics; Property composition relationship; Segregation; Mechanical properties; Annealing temperature; Composition effect; Experimental study; Heat treatments; Tensile strength; AES; Ferrite; Alpha phase; Aluminium additions; Steels; Thermal annealing; Impurity segregation
• DOI: 10.1016/S1359-6462(98)00010-4
• EISSN: 1872-8456
• ISSN: 1359-6462

Fracture behaviors of Al-containing alloys with annealing temperature have been investigated. The 0.1% Al alloy showed a mixed mode of intergranular and cleavage fracture after annealing at 900 deg C, in which the intergranular fracture was due to sulfur segregated at grain boundaries. The fracture mode of the alloy, however, changed to cleavage after re-annealing in the temperature range of 600-800 deg C. The 1.5 and 3.0% Al alloys showed complete cleavage fracture behavior after annealing or subsequent re-annealing in the temperature range of 600-900 deg C. This may be attributed to the repulsion of sulfur by aluminium from the grain boundaries which results in the increase in grain boundary strength. The grain boundary embrittlement by Al itself was not observed in the composition range of the present Al-containing alloys.