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In order to provide a sufficient theoretical basis for the fatigue‐resistant design of the aircraft wheels, strain‐controlled low‐cycle fatigue (LCF) tests were carried out on specimens machined in the extrusion direction (ED) and transverse direction (TD) of die‐forged 2014 aluminum alloy wheels. Although the TD specimens have lower tensile strength and yield strength, the fatigue test results show that the TD specimens have superior fatigue life compared with the ED specimens at total strain amplitudes of 0.5–0.8%. This is predominantly caused by the coarse Al12(MnSi)2(FeCu) intermetallic particles close to the surface layer, which results in a relatively short crack initiation stage for the ED specimens. In contrast, TD specimens with finer and more uniform recrystallized grains exhibit more excellent resistance to fatigue crack initiation (FCI) and propagation (FCP). Moreover, the fatigue life of alloys could be accurately predicted via a Manson–Coffin–Basquin (MCB) model based on total strain. Highlights: A new die forging method was used to fabricate the aircraft wheel.Fatigue characteristics and fracture behavior of aircraft wheels were explored.The accuracy of different fatigue life prediction models was evaluated.Coarse Al12(MnSi)2(FeCu) intermetallic particles affected fatigue crack initiation. [ABSTRACT FROM AUTHOR]

• Fatigue strength anisotropy was related to the degree of plastic deformation. • Quantitative analysed the effect of fatigue crack initiation on fatigue life. • A new fatigue life model was established considering inclusions number. • Second-phase particles, crack closure and twist angle induced FCP anisotropy. The high-cycle fatigue (HCF) property and fatigue crack propagation (FCP) behavior of aircraft wheels manufactured by die forging were investigated from two sampling directions (rims and discs). The results indicate that the HCF anisotropy of the rim and disc specimens increases with decreasing stress amplitude, and the fatigue strengths are 181 MPa and 157 MPa, respectively. Based on the quantitative analysis of the fatigue fractures, a fatigue life prediction model considering the Fe/Mn-containing particles quantity factor S has been established, and the predicted values are reasonably accurate to the test values. The crack path microstructure indicates that Fe/Mn-containing particles can cause crack deflection while acting as bridges for FCP; Crack closure induced by oxides and plastic zones significantly decelerated the FCP rate. Additionally, fatigue cracks tend to propagate toward grains with smaller twist angles and higher Schmid factors (SF). [ABSTRACT FROM AUTHOR]

A controllable method for the synthesis of Mn x Co 3- x O 4 (x = 0.4, 0.8, 1.0, 1.2) spinel coatings with unique microstructures and high-temperature oxidation resistances for solid oxide fuel cells is crucially desired. Herein, we report the synthesis and analysis of synthesized coatings with different phase compositions of ferritic stainless steel interconnects. The coatings are fabricated using a sol-gel dip-coating method. Multiple experimental results confirm that the Mn x Co 3- x O 4 coatings exhibit the advantages of having fine grains and uniform density. Furthermore, the as-prepared Mn 1.2 Co 1.8 O 4 coating has a low coefficient of thermal expansion (11.98 × 10-6 K-1), matching that of ferritic stainless steel, which effectively improves the anti-stripping property of the materials. In particular, oxidation tests illustrate that the oxidation weight gain of this coating decreased by 84.4% compared with bare ferritic stainless steel after 3600 h. The area-specific resistance (ASR) results indicate that the ASR value of the Mn 1.2 Co 1.8 O 4 -coated sample reduced by about 70% compared with those of the ferritic stainless steel samples, which demonstrates its desirable high-temperature oxidation resistance property. It is hoped that this work stimulates new research ideas for the development of spinel oxide coating. [ABSTRACT FROM AUTHOR]