Quantitative characterization of spatial arrangement of shrinkage and gas (air) pores in cast magnesium alloys

Mg-Al-RE Magnesium Alloys for High-Pressure Die-Casting

“…High-pressure die-cast magnesium components are being increasingly used because of their excellent cast ability and the properties that magnesium offers. The high-pressure diecasting of thin-walled components is particularly suitable because of the excellent flow characteristics of molten magnesium alloys [1][2][3][4][5][6][7][8][9].…”

“…The melting of magnesium is also different from other metals because it requires protection against surface oxidation. It should be noted that magnesium and aluminum die-casting alloys also possess different chemical and physical properties, which require modifications in the injection parameters and die design [2][3][4]8]. The lower density of magnesium vs. aluminum signifies that the inertia is lower, and for the same metal pressure a higher flow speed results.…”

Endurance limit of die-cast magnesium alloys AM50hp and AZ91hp depending on type and size of internal cavities

“…The authors visualise the three-dimensional inhomogeneity distribution and describe its effect on mechanical strength values. A quantitative description of spatial arrangement of shrinkage cavities and gas pores in cast Mg alloys of the AM series is given by Balasundaram and Gokhale [3]. Liu et al also describe the influence of porosities on mechanical characteristic values of the alloys AZ91hp, AM50hp, AS41, and AE42 [4].…”

A Model for Gas Microporosity in Aluminum and Magnesium Alloys

“…[16] In contrast to the efforts devoted to Al-based cast alloys, however, few studies modeling porosity formation in magnesium alloys have been done. Several experimental studies on porosity measurement in magnesium-alloy castings are available in the literature, [17][18][19][20][21][22][23] but none is found that study porosity formation in controlled solidification conditions. Mikucki et al [17] quantified the relationship of dissolved hydrogen gas and microporosity for AZ91.…”

“…Experiments have also been performed to quantitatively characterize the gas porosity and shrinkage porosity distributions in magnesium-alloy castings. [18][19][20][21] Unfortunately, the initial hydrogen content in the alloy before casting and the cooling rate during the casting were not measured, and the results cannot be compared with the modeling predictions. Because the solubility of hydrogen in magnesium is much higher than it is in aluminum, one would think that the microporosity in a magnesium casting could be mainly attributed to the shrinkage that results from inadequate feeding.…”