Fatigue Behaviour and Fracture Mechanism of an Extruded AZ61 Magnesium Alloy

Ductility Improvement of an AZ61 Magnesium Alloy through Two-Pass Submerged Friction Stir Processing

Friction stir processing (FSP) has been considered as a novel technique to refine the grain size and homogenize the microstructure of metallic materials. In this study, two-pass FSP was conducted under water to enhance the cooling rate during processing, and an AZ61 magnesium alloy with fine-grained and homogeneous microstructure was prepared through this method. Compared to the as-cast materia...

Fatigue behaviour and fractography of extruded AZ80 magnesium alloys in very high cycle regime

In order to investigate the fatigue properties of extruded magnesium alloy in very high-cycle regime, rotary bending fatigue test was performed in ambient atmosphere at room temperature using the hourglass shaped specimens of AZ80 alloys extruded (Fspecimen) and treated by an artificial aging after extrusion (T5-specimen). From the experimental results, both specimens show a clear step-wise S-N...

Effect of Stress Ratio on Fatigue Crack Growth Behavior of Magnesium Alloy AZ61 under 3.5 Mass% NaCl Spray Environment*

Fatigue crack growth behavior of AZ61 magnesium alloy was investigated in low humidity (55% relative humidity) and 3.5% NaCl spray environments under various stress ratios. Fatigue crack growth rates became higher with increasing load ratio for both environments. However, the results of fatigue crack growth test under 3.5% NaCl spray environment showed lower fatigue crack propagation rate compa...

Microstructure-sensitive investigation of magnesium alloy fatigue

Grain Refinement and Enhancement of Mechanical Properties of Hot Extruded Rare-Earth Containing Magnesium Alloy

The effects of rare earth addition and hot extrusion process on the grain refinement of magnesium alloy were studied. The as-cast Mg-6Al-1Zn (AZ61) alloy had the average grain size of ~ 64 µm and its microstructure consisted of α-Mg and Mg17Al12 phase. By partial substitution of Al with Gd to reach Mg-4.8Gd-1.2Al-1Zn alloy, it was observed that the Mg17Al12 phase disappeared and two new interme...