ABSTRACT
Temper embrittlement and long-term embrittlement have long been known as deleterious phenomena in low alloy steels. Both cause a loss of ductility when the steels are slowly cooled through a critical temperature range or undergo longterm application in the range of about 350—550°C. These phenomena cause a tendency to brittle intergranular fracture of the materials instead of cleavage at low temperatures or instead of ductile fracture at higher temperatures and can be characterized by the fracture energy in the notch impact test. Other properties, such as those determined in the tensile test, are not impaired by these phenomena.
