University of Kentucky, Lexington, Ky.
Chairman, Department of Materials Science, Oregon Graduate Center, Beaverton, Ore.
Pages: 16 Published: Jan 1981
Toughness testing of a quenched and tempered AISI 4340 steel has been carried out by precracked Charpy (instrumented and slow-bend) and fracture toughness test techniques. Results show that the toughness values, as a function of heat treatment, follow similar trends for identical heat-treatment schedules in each type of testing. Fractographic observations also indicate the same fracture initiation mode in all the tests for identical heat treatments, including an intergranular fracture mode associated with the temper embrittlement of the steel in question. It indicates that, in this particular application, mechanical testing variables such as specimen dimensions, crack length, crack length to width ratio, and strain rate have no effect on the fracture initiation process.
fractography, toughness, heat treatment, AISI 4340 steel, materials, materials science, mechanical testing variables
Paper ID: STP33429S