Elastic fields of (774)γ[4 4 $\overline {14} $ ]γ crystons and the formation of a lath structure of bainitic ferrite

Abstract

An analysis has been performed for elastic fields of crystons that simulate the carriers of shear deformation on planes close to the habit plane of the additional to {558} γ component of the bimodal distri bution of ferrite habits in a bainite macroplate. The conclusion has been drawn that the additional component arises according to the same mechanism as the main component, but in the region of austenite with a twin orientation.

Crystons: basic ideas and applications

“…As compared with separate loops, crystons have a modified angular distribution of the elastic field (primarily, due to a change in the Burgers vectors), as well as a cumulative effect ensuring strengthening of the field. This variant of the influence of crystons on the formation of CIM illustrates in pretty much detail the results described in [31].…”

Possibility of wave control of the formation of twinned austenite in the process of the formation of bainitic ferrite

“…In particular, this approach demonstrates good reproduction of the conditions needed to obtain the initial DNCs. In [7], we concluded that the data of the experiment and analysis speak in favor of the hypoth esis on the formation of ferrite laths with habit planes (774) γ in austenite regions with a twin orientation. In connection with this, the problem arises of determin ing how twinned austenite regions are formed.…”

“…As has been shown in [5,7], the decisive role in the description of the habits of the {hhᐉ} γ type belongs to the segments of the DNCs located along the close packed directions Λ 1 The formation of each ferrite lath is accompanied by a macroshear with the principal component lying in the habit plane.…”

“…Here, unlike [5,7], instead of analyzing fields of most intense extrema, we focus on the regions near the less intense extrema lying at θ ≈ -94°, -85° , 95°, and 84° in Fig. 3.…”

“…In our previous works [4][5][6][7], the formation of a macroplate of bainitic ferrite has been considered based on the assumption that the lath crystals in the macroplates that arise in the supersonic regime via the martensitic mechanism [8,9]. This means that, in the elastic fields of defects, there are local regions with lowered interphase barriers for the appearance of ini tial excited states (IESs) in the form of extended rect angular parallelepipeds.…”