Very high cycle fatigue characterization of additively manufactured AlSi10Mg and AlSi7Mg aluminium alloys based on ultrasonic fatigue testing

Abstract

This paper investigates long fatigue life characteristics of AlSi10Mg and AlSi7Mg aluminium alloys produced using direct metal laser sintering. An inhouse built ultrasonic fatigue testing machine was used to carry out fatigue tests on specimens machined from heat-treated AlSi10Mg and AlSi7Mg alloys subjected to constant fully reversed tension-compression loadings. The fatigue life data acquired for these two additive manufacturing (AM) aluminium alloys were compared with previously published data under heat treatment and nonheat treatment conditions. It was found that fatigue data of tested specimens fit more closely the data of specimens without any heat treatment. Fatigue test results indicate that effects of heat treatment on high cycle fatigue (HCF) and very high cycle fatigue (VHCF) performance of AM alloys should be further investigated in the context of the microstructural changes.

Very high cycle fatigue (VHCF) response of additively manufactured materials: A review

“…50 Note: The legend in the plot link to literature VHCF data which are in this paper renumbered as Tridello et al 43 (Yamashita et al 23 in the plot) Tridello et al 40 (Tridello et al 39 in the plot). For the other references about HCF data, the reader is referred to Lesperance et al 50 [Colour figure can be viewed at wileyonlinelibrary.com] investigation of the influence of the BPH, 38 of the heating temperature on residual stresses in SR heat treatments, 40 of size-effects, 44 of the stress ratio, 48 of the building orientation, 42,44,48 and of the powder size. 49 In all the cases, the defects control the VHCF response and are responsible for the fatigue crack initiation.…”

“…S‐N plot of (A) AlSi10Mg batch compared with literature AlSi10Mg heat‐treated data and (B) AlSi7Mg batch compared with literature cast AlSi7Mg data from Lesperance et al 50 Note: The legend in the plot link to literature VHCF data which are in this paper renumbered as Tridello et al 43 (Yamashita et al 23 in the plot) Tridello et al 40 (Tridello et al 39 in the plot). For the other references about HCF data, the reader is referred to Lesperance et al 50 [Colour figure can be viewed at wileyonlinelibrary.com]…”

“…In Lesperance et al 50 the VHCF response of machined and heat‐treated SLM AlSi10Mg and AlSi7Mg alloys is investigated. Cylindrical specimens are manufactured vertically with an SLM machine (EOS M290) with a laser power of 370 W and with a preheating temperature of 180°C, following ISO 4497 standards.…”

Influence of 3D Printing Topology by DMLS Method on Crack Propagation

“…The effects of surface roughness on the low-cycle [ 31 ] and high-cycle fatigue [ 32 ] life are not a negligible parameter for a different type of metal alloy due to the crack initiation period [ 33 , 34 , 35 ]. Certainly, the behavior of materials during low-cycle fatigue will have an effect, as well as a heat treatment effect [ 32 ], anisotropy, grain characteristics, defects, surface roughness, and residual stresses [ 36 , 37 ].…”

Small‐sized specimen design with the provision for high‐frequency bending‐fatigue testing

“…6,7 Although torsional 8 and three-point bending multiaxial 9 ultrasonic fatigue tests were later developed, high-frequency uniaxial tension-compression fatigue testing studies are more studied in the literature. [10][11][12] Ultrasonic fatigue tests are generally carried out on specimens of sufficient length to resonate in ultrasonic frequency. Methods for the ultrasonic fatigue testing of various designs such as cruciform specimen 13 -biaxialand even thin sheets have also been developed.…”