Porosity and Mechanical Properties of Squeeze Cast and Permanent Mold Cast Wrought Mg Alloy AZ31

Wrought magnesium alloy AZ31 withWrought magnesium alloy AZ31 a thick section of 20 mm was prepared by squeeze castingSqueeze Casting (SC) and permanent steel mold castingPermanent Steel Mold Casting (PSMC). The yield strength (YS), ultimate yield strength (UTS), elongation (ef), and strain-hardening rate of the cast AZ31 specimens were evaluated by tensile testing. The measured engineering stress versus strain curves showed that the SC AZ31 alloyAZ31 alloy exhibited 62 MPa in YS, 194 MPa in UTS, and 13.8% in ef, while the YS, UTS, and ef of the PSMC AZ31 specimen were only 58, 173 MPa, and 9.9%. The results of the tensile testing evidently showed that the YS, UTS, and ef of the SC AZ31 alloy were 7, 12, and 39% higher than those of the PSMC counterpart. The calculated resilience and tensile toughness indicated that the SC AZ31 was more capable of resisting energy loads in elastic deformation and had an ability to absorb energy during plastic deformationPlastic deformation without fracture than that of the PSMCPermanent Steel Mold Casting AZ31. Also, the analyses of the true stress versus strain curves revealed that, upon the onset of plastic deformationPlastic deformation, the strain-hardening rate of the SC AZ31 sample was 10,000 MPa, which was 25% higher than that (8000 MPa) of the PSMC AZ31 specimen. The obtained mechanical propertiesMechanical Properties showcased the fit of the casting process to wroughtCast/wrought processing magnesiumMagnesium AZ31 alloyAZ31 alloy, which was squeeze castingSqueeze Casting. The porosityPorosity measurements of the SCSqueeze Casting and PSMCPermanent Steel Mold Casting showed that the SC AZ31 had a porosity of 1.13%, which was the 57% lower than that (2.66%) of the PSMC AZ31 counterpart. The low porosity level of the SC AZ31 alloy should be somewhat responsible for its high mechanical propertiesMechanical Properties.