Low temperature brittle fracture of austenitic Fe-Mn alloys

Technical Report · Thu May 01 00:00:00 EDT 1986

OSTI ID:5701615

Xue, K S

The ductile-to-brittle transition of high manganese austenitic Fe-Mn alloys is accompanied by a change in the fracture mechanism from microvoid coalescence to intergranular fracture. No impurity element segregated to grain boundaries was found. The results of AES analyses indicate that manganese segregates to the grain boundaries. The magnitude and extent of manganese segregation to grain boundaries increases with increasing manganese content. The manganese segregation is a kind of nonequilibrium segregation. Increasing solid-solution treatment temperature and the following cooling rate, the manganese segregation to the grain boundaries is increased. Increasing the manganese content of Fe-Mn alloys, solid-solution treatment temperature and the following cooling rate, the ductile-to-brittle transition temperature and intergranular fracture are increased. These results indicate that the intergranular fracture and embrittlement of high manganese austenitic Fe-Mn alloys at low temperature are caused by manganese segregation. The possible mechanism for intergranular fracture of these alloys and the way to improve low-temperature toughness of high manganese steels are discussed. 61 refs., 36 figs.

• Research Organization: Lawrence Berkeley Lab., CA (USA)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 5701615
• Report Number(s): LBL-20938; ON: DE86012799
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
ALLOYS
CRYSTAL STRUCTURE
DUCTILE-BRITTLE TRANSITIONS
ELEMENTS
EMBRITTLEMENT
FRACTURE PROPERTIES
GRAIN BOUNDARIES
IRON ALLOYS
IRON BASE ALLOYS
MANGANESE
MANGANESE ALLOYS
MANGANESE STEELS
MECHANICAL PROPERTIES
METALS
MICROSTRUCTURE
PHYSICAL PROPERTIES
SEGREGATION
STEELS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENTS
TRANSITION TEMPERATURE