Speaker
Description
Maraging steels are attractive alloys for engineering applications requiring high strength, good fatigue, and fracture properties. Although Maraging steel is usually used in room temperature or elevated temperature applications, it has found a place in cryogenic applications. Cryogenic data for maraging steels in the literature is limited. Since it is a precipitate-hardened martensitic steel, fatigue and fracture properties at low temperatures are of concern. Preliminary examinations reveal that at 77K, this alloy can operate at a cyclic stress value of 1000 MPa (r=0.1), for greater than 106 cycles. Here, we report on tensile and fracture toughness properties, axial fatigue life data (S-n curves, R = 0.1), and fatigue crack growth rates on commercially available C-250 maraging steel at cryogenic temperatures. Metallographic evaluations of microstructure and fracture surfaces will be presented to correlate structure-property relationships.
