LOCAL STRENGTHENING METHOD OF AXIALLY SYMMETRICAL BLANKS BY MEANS OF SHIFT DEFORMATIONS Russian patent published in 2008 - IPC C21D7/13 B21J5/00 

FIELD: plastic working of metals, possibly local strengthening of hollow and solid blanks of axially symmetrical parts of iron-base mean- and high-alloy steels and alloys.

SUBSTANCE: method comprises steps of plastically deforming blank rigidly fastened between clamps and heated till temperature no less than phase conversion ending temperature and no more than recrystallization starting temperature due to rotating at least of one clamp. Deformation is realized at rate and deformation degree sufficient for providing dynamic recrystallization processes but not causing stability loss at plastic deformation related to energy dislocation. Deformation is performed near peripheral layer of blank. Due to dynamic crystallization maximally possible grain size disintegration in near-surface region is achieved and gradient structure is created along cross section and length of blank.

EFFECT: improved physical and mechanical properties in near-surface of blank, lowered cost of strengthening process.

7 cl, 1 dwg, 1 ex