Charles D’Ambra

Charles D’Ambra

Mechanical and Microstructural Characterization of HY-80 Steel


Charles D’Ambra, Jason Schibler, Michael Roberts, Michele V. Manuel, Thomas W. Krause, Aroba Saleem


Dr. Aroba Saleem


Herbert Wertheim College of Engineering


HY-80 is a low-alloy, low-carbon steel used primarily in submarines for its high strength and high toughness. HY-80 steel is susceptible to temper embrittlement caused by the migration of impurity elements and carbides towards the grain boundaries when held between the embrittling range of 370 to 600 ºC. Temper embrittlement results in the loss of ductility and reduction of impact toughness of the material. There is currently no widespread non-destructive method for testing of early stages of temper embrittlement of HY-80 steel. The purpose of this project is to analyze the microstructural development and changes in mechanical properties to determine their relation to magnetic properties. Samples of HY-80 were heat treated at 525 °C for different holding times to induce varying degree of temper embrittlement. Before and after heat treatment, samples were characterized by scanning electron microscope (SEM). In addition, hardness measurements were taken before and after heat treatment using Vickers microhardness testing. It was observed that hardness varied with holding time, and these changes were attributed to the change in carbide precipitate density, size, and location within the matrix.


Hover over the image below to zoom in or click to view full screen.

Research Pitch

View a 3-minute research pitch below.

To comment below, please sign in with Facebook or Google (using your ufl account) by clicking the little round icons to the right. If you decide, you can post as a guest by entering name and email below, but will lose some features. You can also subscribe to the student’s page to get email updates on new comments.

Leave a Reply