Analysis of Ultrasonic Fatigue on an Austenitic Steel at High Temperature

FEDERICO J. CAVALIERI; CLAUDE BATHIAS; NICOLAS RANC; ALBERTO CARDONA

Universidad Nacional de San Luis

Congreso; ENIEF 2008 XVII. Congreso sobre Métodos Numéricos y sus Aplicaciones; 2008

Asociación Argentina de Mecánica Computacional

In this work, an ultrasonic fatigue technique is presented to study the fatigue behavior on anaustenitic steel at high temperatures, which is employed on combustion internal engines valves with a stress under fully reverse loading (R = -1) in the lifetime range from 10^5 to 10^9 cycles. To carry out the fatigue tests at high temperatures, an induction coil heating equipment was employed to achieve temperatures as high as 600ºC and 700ºC on the specimens. Then, as Young modulus is function of temperature, its value changes when the specimen is heated, so we intend to analyze with a numerical methodology by finite element method (FEM), the effects of the variation in the Young modulus due to temperature from the measurement of the ultrasonic resonance frequency. Thermal, Thermo-mechanical and modal analysis by FEM was used for designing the specimens at test temperatures. SAMCEF commercial software was employed to numerical simulations.10^5 to 10^9 cycles. To carry out the fatigue tests at high temperatures, an induction coil heating equipment was employed to achieve temperatures as high as 600ºC and 700ºC on the specimens. Then, as Young modulus is function of temperature, its value changes when the specimen is heated, so we intend to analyze with a numerical methodology by finite element method (FEM), the effects of the variation in the Young modulus due to temperature from the measurement of the ultrasonic resonance frequency. Thermal, Thermo-mechanical and modal analysis by FEM was used for designing the specimens at test temperatures. SAMCEF commercial software was employed to numerical simulations.