Inclusions in High-Strength and Bearing Steels. Their Dependence on Processing Variables and Their Effect on Engineering Properties.

摘要

The relationship between quantity and type of nonmetallic inclusions and critical mechanical properties was determined for the high-strength steels, 4340and 300M,and the bearing steel, 52100,through the use of a quantitative television microscope (QTM),an ultrasonic volume inspection system and various identification methods. For the structural steels,transverse reduction of area was the property most influenced by inclusion content. Fatigue and impact properties were also affected,though to a lesser degree. Plane strain fracture toughness was little affected by inclusion content and,in fact,longitudinal and transverse properties were substantially the same in direct contrast to reduction of area,impact and fatigue properties. (Author)