Change of Parameters of the Koiwa–Hasiguti Dynamic Dislocation Relaxation in Nanostructured and Polycrystalline Zirconium after Severe Plastic Deformation and Annealing

Table 1

Preparation schedules and basic characteristics of the samples.

Sample	, μm		Preparation scheme	Post-SPD annealing
Zr-CG [7]	150	0.3	A (1073 K, 4 h.)	—
Zr-HEA	12	0.85	HE (4.1) + A (853 K, 1 h.)	—
Zr-HEAD	2	0.71	HE (4.1) + A (853 K, 3 h.) + D (0.56)	—
Zr-0	0.392	0.66	HE (4.1) + A (853 K, 3 h.) + D (2.4)	А (425 K, 1 h.)
Zr-01	0.117	0.35	HE (4.1) + D (2.4)	А (425 K, 1 h.)
Zr-02RT	0.113	0.32	HE (1.1) + CD (4) + D (2.4)	А (425 K, 1 h.)
Zr-02CE	0.100	0.28	HE (1.1) + CD (4) + D (1.4) + CE (1.0)	А (425 K, 1 h.)

A means annealing (annealing temperatures and its duration are given in parentheses), HE means “hot” extrusion at the temperature 795 K, D means drawing at room temperature, CD means cyclic deformation at room temperature, CE means cryoextrusion at 77 K, and is the coefficient of variation, characterizing homogeneity of a grain-size distribution. In parentheses, the values of the “true” plastic deformation e are presented (Section 2 in the text).