IMPACT TOUGHNESS OF SHIP STEELS AND ESTIMATION OF THEIR SUSCEPTIBILITY TO BRITTLE-FRACTURE

The present paper concerns a new method for determining the cold-britt leness temperature T-c.b. in tests for impact toughness. Results of es timation of metal quality based on conventional characteristics and th e suggested parameter of resistance to defects are compared for ship s teels 10KhSND and 12KhN3. Impact toughness is essentially an integral characteristic of a metal. The energy capacity of fracture depends on the strength and ductility simultaneously, as well as on the test cond itions and the shape of the specimen, which in many cases makes estima tion of metal quality ambiguous. The authors consider nontraditional a pproaches to determination of the embrittlement action of various stre ss concentrators. The aim of the work consists in establishing a relat ion between the universally used mechanical properties determined in i mpact toughness tests and toughness parameters such as K-t (toughness coefficient) and D-2 (resistance to defects).