Page 104 - eBook_Proceedings of the International Conference on Digital Manufacturing V2

Proceedings of the International Conference on Digital Manufacturing –
Volume 2

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/2 h (Regime: Cryo + Temp) (Jirková, Rubešová, Jeníček, Hradil
& Kučerová, 2022).

Semi-Solid Thixotropic Forging Forming (STFF)

Another technique applicable to ferrous metal is the Semi-Solid
Thixotropic Forging Forming (SSTFF) process (Figure ) which
has been widely utilised for light alloys (Li, Wang, Li, Liu &
Zhao, 2023; Zhao, Li, Yan, Zhang & Wu, 2019). However, its
application to ferrous materials, particularly low-carbon steel,
remains limited due to challenges such as high melting point, easy
oxidation, and narrow semi-solid temperature range (Li, Wang,
Li, Liu & Zhao, 2023; Rubešová, Peković & Jirková, 2017;
Jirková, Rubešová, Konopík & Opatová, 2018) . While previous
research has predominantly focused on non-ferrous metals, there
remains a significant gap in the literature concerning the semi-
solid forming of low carbon steel. A study was done to bridge this
gap by investigating the SSTFF process for AISI 1010 low-carbon
steel claw pole (Li, Wang, Li, Liu & Zhao, 2023). The research
employed a combination of numerical simulations and
experimental methods. At an early stage, the low-carbon steel bar
underwent radial forging to achieve sufficient plastic deformation.
The radial-forged billets were then subjected to isothermal heating
at different temperatures and holding times to obtain ideal semi-
solid microstructures.

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