The effect of heat treatment on fatigue strength of additively manufactured AlSi10Mg

Abstract

This research aims to analyze how varying heat treatment conditions affect the fatigue life performance of additively manufactured specimens from AlSi10Mg. The study focuses on the transition from High Cycle Fatigue (HCF) to the Fatigue Limit (FL) domain. To eliminate inconsistencies, four sets of hourglass specimens were created through Laser Power Bed Fusion (L-PBF) technology within one build cycle. All fatigue specimens were of the same geometry and with as-built surface, but four different heat treatments were applied. Fatigue testing was conducted in the uniaxial tension domain using a resonant pulsator with the load ratio of 0.1. To further characterize the different heat treatments of the specimens, a thermal camera was utilized to measure the temperature response during cyclic loading. The observed increase of temperature, referred to as the Self-Heating effect (S-H), is directly related to heat dissipation during cyclic loading. A test with blocks of subsequently increasing load amplitude was conducted to establish a stabilized temperature response in each block for further analysis. The pairs of the stress amplitude levels, and stabilized temperatures can be used as a characteristics of heat dissipation during cyclic loading related to different heat treatments.