Page 13 - eBook_Proceedings of the International Conference on Digital Manufacturing V2

Figure 30: Representative microstructure (a) dendritic
morphology resulting from conventional
solidification, and (b) globular, non-dendritic
particles produced through intensive forced
convection in SSMP 72
Figure 31: A schematic of thixotropic behaviour of semi-
solid emulsions 75
Figure 32: Dendritic and globular structures in a semi-
solid alloy, along with a basic eutectic phase
diagram for X210CrW12 steel 76
Figure 33: Microstructural changes resulted from grain
refinement: (a) untreated sample without grain
refinement addition, (b) with 1300 ppm Ti and
210 ppm B addition 80
Figure 34: EBSD images showing grain structure: black
lines mark grain boundaries over 10 degrees
misorientation. (a) no additives, (b) with 1300
ppm Ti and 210 ppm B 81
Figure 35: Schematic diagram of the DTM setup 82
Figure 36: Microstructures observed at various pouring
temperatures and holding times: (a) 685 °C,
60s; (b) 685°C, 40s; (c) 685°C, 60s; (d) 665°C,
60s; (e) 665°C, 40s; and (f) 665°C , 20s 83
Figure 37: Microstructure development for samples (a)
S660-20 and (b)S680-60 85
Figure 38: Forming deformation sequence for the case
involving five (5) deformation steps 87
Figure 39: Microstructure after processing through semi-
solid state with ten (10) deformation steps. (a)
Following cryogenic treatment at 160 °C for 24
hours (Regime: Cryo); (b) Following cryogenic
treatment at 160 °C and 24 hours combined
with tempering 300 °C/2h (Regime: Cryo
+ Temp) 88
Figure 40: Process diagram of the SSTFF method for the
claw pole: (a) initial deformation stage, (b)
isothermal treatment stage, and (c) final
forming stage 89

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