By means of heavy cold rolling and annealing,
Fu etal. realized rapid cementite spheroidizing and obtained
(aþy) micro-duplex structures inFe–0.8 C steel.Furuhara also
obtained (aþy) micro-duplex structures in Fe–1.4 Cr–1.0 C steel
using the same method. Lvetal. investigated the coarsening
kinetics of y particles in severely cold rolled and annealed pearlite
in Fe–0.8C mass% alloys.They discussed the effect of alloying
elements on the coarsening behavior of cementite. SunandXiong
successfully producedan ultrafine (aþy) structure through
warm cross-wedgerollingattheouterlayerofFe–0.8Csteelrods
where equiaxed a grains and fully spheroidized y particles are in
submicron scale.Ohetal. obtained ultrafine-grained structures with micron cementite particles in high carbon steel during
warm caliber rolling . Recent investigations have established the
potential of cyclic heat treatment techniques to accelerate cementite spheroidizing processes without deformation in steels
Saha etal. investigated the microstructure and mechanical properties of 0.16%,0.6%, and1.24% carbon steels during
cyclic heat treatment.Through cyclic heat treatment,they realized rapid cementite spheroidizing without deformation and
obtained micron y particles after several cycles.Each cycle
in their works comprises short-duration (several minutes)at
above Ac3 (Acm) temperature followed by forced air-cooling to
room temperature. In the seinvestigations, the non-equilibrium
temperature reversal effect during cyclic thermal treatment is explained as the prime factor causing excitation of atoms,there by
reducing the activation energy and enhancing the process
kinetics.