The two-phase mixture of ferrite and cementite that constitutes "pearlite" is a wonderful example of cooperative growth. The ferrite and cementite share a common transformation front with the austenite, and in Fe-C, the average composition of the pearlite is precisely the same as that of the austenite, meaning that growth occurs at a constant rate. The theory for the growth of pearlite is deriver, and its strength and toughness rationalised, both in terms of interlamellar spacing and nodule size. Some quite spectacular applications of pearlite are illustrated.
The process and consequences of wire drawing and rope manufacture are also covered, including the classic Embury and Fisher equation.
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H. K. D. H. Bhadeshia
Steels: Pearlite
Теги
steelssteelmetallurgythermodynamicsphase transformationssolid statecarbon diffusion controlled growthreconstructive transformationallotriomorphic ferritediffusion controlled growthferriteparabolic growthH. K. D. H. BhadeshiaHarry BhadeshiaBhadeshiaUniversity of CambridgeInterphase precipitationpearlitecementiteinterlamellar spacingHall-Petch equationcleavage fracturedivergent pearlitewire drawingsteel wiresteel ropes