Effect Of Texture And Grain Size On Mechanical Properties Of Wrought Magnesium Alloy AZ31

Recently, plenty of research work about wrought magnesium alloy isfocused on the effect of microstructure (grain size and texture) on its mechanical property.However, there aren't any publications that can separate the two microstructure factors forobserving their contribution to the mechanical property respectively and quantificationally,which is because of the complex interactions and joint operations of grain size and texture.In this work, a combined of Equal Channel Angular Pressing and Forward Extrusionmethod was employed to AZ31 magnesium alloy for preparing samples with fine grainsand different textures successfully. Then annealing was introduced to the ECAP 4-Pass and4P+Extrusion samples respectively to get the alloys with different grain sizes while thetextures were considered being unchanged. So far, the two factors that were grain size andtexture which made the most contribution to its mechanical property in AZ31 have beenseparated reasonably.Pole figures and Orientation Distribution Function (ODF) of AZ31 in different stateswere analyzed to reveal the mechanism of how texture performing on the Hall-Petchrelation. Tension and Compression yield asymmetry in wrought magnesium alloys wasalso discussed.The results show that, the tensile yield strength and grain size in both ECAP 4-Pass and4P+Extrusion samples which have different textures obey the Hall-Petch relation. That are,σ0.2=-1.12+327.01d^-1/2 in ECAP 4-Pass andσ0.2=51.21+343.15d^-1/2 in 4P+Extrusion. Theeffect of texture is that it changes the vertical intercept of Hall-Petch line, while grain sizedetermines the slope of Hall-Petch equation in AZ31. A fitting formula between (Compressyield stress) CYS/(Tensile yield stress) TYS and grain size d is also gained at last, that isCYS/TYS=1.02-0.121nd.