Alloying behavior, microstructure and mechanical properties in a FeNiCrCo0.3Al0.7 high entropy alloy

Corrosion of hot extrusion AZ91 magnesium alloy. Part II: Effect of rare earth element neodymium (Nd) on the corrosion behavior of extruded alloy

Tubular channel angular pressing (TCAP) as a novel severe plastic deformation method for cylindrical tubes

Microwave processing of materials has emerged as a new method for processing of a variety of materials in the recent years. Microwaves have been used effectively with significant advantages, particularly in food processing and chemical synthesis. They are also found to be efficient for processing polymers, ceramics, polymeric composites, and ceramic composites. The physics of interaction of microwaves with characteristically different materials is not yet explored well; consequently, there are challenges in microwave processing of metal-based materials. Industrial processing of bulk metal is yet to be popular in spite of the fact that the feasibility of metal powder sintering was demonstrated a few decades ago. This article provides a summary of fundamental aspects of microwave processing of metal-based materials and their interaction with metallic materials. The processing challenges have been surveyed; developments in terms of techniques and tooling have been analyzed. Possible effects of microw...

A Review of Research Trends in Microwave Processing of Metal-Based Materials and Opportunities in Microwave Metal Casting

Fabrication and properties of nanocrystalline Co0.5FeNiCrTi0.5 high entropy alloy by MA–SPS technique

A multitemperature multi-axial forging (MAF) procedure has been developed to produce a fine-grained AZ61 alloy. The results show that the microstructure can be effectively refined with increasing equivalent strain during MAF. Once dynamic recrystallisation is completed, the alloy is in a steady state and further deformation of the alloy cannot change the grain size. The multitemperature MAF procedure can produce a fine-grained AZ61 alloy giving a grain size of 8 μm. This fine-grained alloy has an excellent strength accompanied by reasonable good tensile ductility. The success of the development of this multitemperature MAF procedure proves that MAF can offer a good opportunity for the development of magnesium alloys with good mechanical properties.

Grain refinement in an as-cast AZ61 magnesium alloy processed by multi-axial forging under the multitemperature processing procedure

Microstructure development and thixoextrusion of magnesium alloy prepared by repetitive upsetting-extrusion

As-cast AZ91D +  x Y ( x  = 0, 0.5, 1, 2 mass%) magnesium alloys were prepared by a simple addition of Y-rich interalloy to AZ91D alloy. Influences of Y on the microstructures and tensile properties of AZ91D alloy were investigated. Influences of extrusion temperature on the microstructure and tensile properties of AZ91D + 2Y alloy were investigated. Moreover, microstructures and the resulting tensile of extruded AZ91D + 2Y alloy were also investigated under different heat-treatment conditions. The results show that the addition of Y to AZ91D alloy refines primary α-Mg matrix and β-Mg 17 Al 12 phase. The addition of 2 mass%Y forms rod-shaped Al 2 Y phase. After hot extrusion, the grain sizes of AZ91D and AZ91D + 2Y alloys are greatly refined through dynamic recrystallisation. At extrusion temperature below 300 °C, the microstructure of AZ91D + 2Y alloy is characterized by fine and equiaxed grains, which leads to a high tensile strength but relatively low elongation. With increasing extrusion temperature up to 400 °C, more equiaxed grains with larger size are obtained. A low strength and large elongation are achieved compared with those extruded at low temperature. The best combination of both high strength and large elongation takes place at 325 °C. As for extruded AZ91D + 2Y alloy, solution treatment at 413 °C (T4) causes parts of broken β-Mg 17 Al 12 phase to be dissolved into α-Mg matrix and the deterioration of tensile properties. During aging at 216 °C (T5), discontinuous precipitates appear at grain boundaries. Solid solution followed by aging (T6) treatment increases ultimate tensile strength but decreases yield strength and elongation.

Microstructures and mechanical properties of AZ91D alloys with Y addition

Microstructure and mechanical properties of SPD-processed an as-cast AZ91D+Y magnesium alloy by equal channel angular extrusion and multi-axial forging

Based on conventional extrusion and equal channel angular extrusion (ECAE), a new severe plastic deformation (SPD) method called compound extrusion is developed to fabricate fine-grained AZ91D magnesium alloys. The fine grain size of 6 μm is obtained as the accumulated strain increased to 9.146. The AZ91D alloy treated by compound extrusion exhibits good mechanical properties, with a yield strength of 202.2 MPa, a tensile strength of 323.1 MPa and an elongation to fracture of 14.8%. The good mechanical properties of AZ91D alloy treated by compound extrusion are due to grain refinement and to the homogeneous distribution of intermetallic particles. The success in development of compound extrusion proves that compound extrusion can offer a good opportunity for the development of good mechanical properties of as-cast magnesium alloys.

Dayu Shu

Papers

Grain refinement in an as-cast AZ61 magnesium alloy processed by multi-axial forging under the multitemperature processing procedure

Microstructure development and thixoextrusion of magnesium alloy prepared by repetitive upsetting-extrusion

Microstructures and mechanical properties of AZ91D alloys with Y addition

Microstructure and mechanical properties of SPD-processed an as-cast AZ91D+Y magnesium alloy by equal channel angular extrusion and multi-axial forging

Microstructure and mechanical properties of AZ91D magnesium alloy prepared by compound extrusion