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Notes: The feasibility of recycling machining grindings of aluminum alloys by semisolid processhas been investigated. Machining grindings of A2011 aluminum alloy produced experimentally bylathe machining were used. The material is put into a metal mold and compressed up to 90 % of thetrue density at room temperature. The metal mold with the compressed machining grindings isheated up to a specified temperature. Afterwards, the metal mold is set into the extrusion container,and extrusion in hot and semisolid range was carried out. In this experimental study, extrusion load,internal structure of the product and mechanical properties (tensile strength, elongation, hardness) ofthe product are assessed. It was proven that semisolid extrusion is about 40% less extrusion loadcompared with that of hot extrusion, the shape of the machining grindings remained in the hotextrusion and the semisolid extrusion products extrusion ratios higher than 10 have excellentelongation property, which is comparable to the commercialized product

Notes: The structural changes of the wrought magnesium alloy AZ31B in semisolid state wereclarified using optical microscopy and hot-stage microscopy. The influence of heat treatmentvariables was assessed. Compression tests covering a range from room temperature to 673 K werecarried out for mechanical property assessment; flow stress and breaking strain were determined. Thefollowing are the results: (1) The grain growth of the hot-extruded AZ31B without preprocessingsensitively reacted at temperature and retention time. (2) The hot-extruded AZ31B with 30 %preprocessing showed an almost perfectly spheroidized structure in a semisolid state under certainconditions. (3) Heating velocity markedly affected the spheroidizing rate of grains. (4) From thedirect observation of the hot-extruded alloy AZ31B by hot-stage microscopy, spheroidization wasobserved in some crystal populations. (5) Spheroided materials in the semisolid temperature rangehad a lower flow stress and a larger breaking strain than nonspheroidized materials. These resultsindicate the possibility of manufacturing wrought magnesium alloy by cold working

Notes: Thixoforming or Semi-Solid Metal Forming offers many advantages in comparison withcasting and conventional forging. The purpose of the present study is to provide the basicmicrostructure and deformation data for austenitic and ferritic stainless steel under mushy state. Aswell known, the stainless steels solidify in different modes according to the different chemicalcompositions. In this paper, microstructural evolution of austenitic stainless steel type 304 whichsolidifies in FA mode ( L → L +δ → L +δ +γ →δ +γ →γ ),austenitic stainless steel type 310Swhich solidifies in A mode ( L → L +γ →γ ), and ferritic stainless steel type 430 which solidifies inF mode ( L → L +δ →δ )[removed info]are investigated during partial remelting by way of SIMA (Strain InducedMelted Activation). The results show that A and F mode of stainless steels melt directly at the grainboundary without phase transformation during reheating. A banded structure, originating from theprimary dendritic segregation of the original ingots, is observed in type 310S steel during furtherheating. On the other hand, a perfect globular and insegregative two-phase semi-solid structure L +δcan be obtained while heated beyond the banded three-phase L +δ +γ semi-solid state in FA modeaustenitic stainless steel type 304. This spheroidization can be attributed to the peritectic reactionoccurred in the L +δ +γ semi-solid state. In addition, simple compression tests of these alloys insemi-solid state for varied combination of deformation rate and deformation temperature areconducted to examine the deformation behavior of stainless steel. Flow stress curves exhibit abruptchange in various alloys, even though in the same alloy such as type 304, various flow stresses areobserved according to the difference in inner microstructure or morphology. Stress of type 310S steelshows the most reduction as the deformation temperature increasing at the same strain rate condition.The Liquid is centralized to periphery by the compression force in all deformed test pieces. Fracture,observed in all alloys except type 304 steel in globular L +δ semi-solid state, should be resultedfrom the lack of liquid in L +δ +γ state of type 304 steel and solidification crack in type 310S andtype 430 steel. Deformation of solid particles occurs only in L +δ +γ state of type 304 steel. Last inthis paper, various deformation mechanisms are proposed for various microstructures