Publications Details

Mechanical Behavior of D-Shaped Hiperco Specimens under Tension Measured by Digital Image Correlation

Chu, Edward; Carroll, Jay D.; Robbins, Aron R.

Hiperco, manufactured by Carpenter Technology Corporation, is the trademark name for an alloy of equal composition iron and cobalt, with 2 percent vanadium added for enhanced mechanical properties (49Fe-49Co-2V). The alloy is interesting due to its very high magnetic saturation and flux density, yet undesirable mechanical properties such as brittleness and low strength. Several Hiperco specimens cut to a "D”-shaped geometry were placed under tension in a load frame, with a constant strain rate at room temperature, until failure occurred. Digital image correlation was used to obtain strain field data throughout the experiment. The data is to be used to compare with a finite element model, to investigate if Hiperco's unusual behavior can be modeled accurately with chosen model parameters. Between the five specimens tested, high-level results were consistent. Maximum strain and ultimate tensile strength all fell within acceptable bounds. However, several qualitative results differed from specimen to specimen. These differing results include the point of failure, the start point of Liiders band formation, as well as the presence or absence of Liiders bands on the curved section of the "D” specimens.