تشكيل رسوبات فاز لاوه در فولادهاي ماراجينگ نورد سرد شده از نوع نيكل-منگنز-موليبدن-تيتانيم با مقادير مختلف كروم

Precipitation of Laves phase particles in the cold-rolled Fe~ Ni-Mn-Mo-Ti maraging steels with different amounts of Cr additions

Iron- nikel- manganese maraging steels with considerable amounts of molybdenum, titanium and chromium for decrease brittleness and grain-boundary fracture are studied. In this research, effect of different amounts of chromium in upper alloys has been investigated. Optical and scanning electron microscopy. X-ray diffraction, tensile and hardness test were used to study of chromium effect on microstructure and mechanical properties of this alloys. The results show that accomplishment of solution-annealed treatment in homogenized and cold rolled alloys causes the formation of laves phase precipitates, Fe2(Mo,Ti), which were stable at high temperatures. Consequently, the presence of these precipitates prevented from recrystallization at high temperatures. As a result, a semi-brittle fracture was occurred at subsequently aging condition. The higher chromium addition cause stability of austenite which are free from laves phase precipitates and aid to elongation of alloy.