Honors Students' Abstracts
Charpy Impact and Fracture Toughness Testing of Hydrogen Charged 4340 Steel
Marc Papakyriakou, Nour Abisamra, Brent Bates, Jose Davila, Yaurel Gonzales, John Jabbra, Ruby Rubio, Sara Tung
The purpose of this research was to study the effect of hydrogen charging on the toughness, as measured through Tensile tests, Charpy Impact tests, and ductile-brittle transition temperature testing of AISI 4340 steel. AISI 4340 steel samples were austentized, quenched, and tempered at different temperatures for two hours ranging from 257 to 593oC to achieve strength values ranging from 145 to 250ksi. Hydrogen content will be introduced through Cadmium at 0.002mm, 0.02mm, and 0.05mm thickness of coatings. All samples charged and un-charged will be tested by evaluating their properties. The advantage of the Tensile tests and Charpy Impact tests in comparison to conventional static and slow strain rate tests used to assess hydrogen embrittlement is that can be performed quickly and inexpensively. 4340 steel is widely used in the aerospace industry; however, it has low resistance to stress corrosion cracking and its susceptibility to hydrogen embrittlement limits its application. Hence, it is important to perform studies to understand and improve the ability of 4340 steel.