PROCESS OF MANUFACTURE OF TUBULAR ARTICLES FROM ZIRCONIUM ALLOYS ( VERSIONS ) Russian patent published in 1998 - IPC

FIELD: manufacture of tubes and tubular articles from binary and multicomponent zirconium alloys. SUBSTANCE: given process involves manufacture of ingot, its preliminary beta-ray deformation machining to obtain initial billet, manufacture of tubular billet by hot formation of initial billet at temperature of existence of alpha-zirconium, cold deformation of tubular billet with intermediate annealings at temperature of existence of alpha-zirconium with summary drawing μ_Σ > 100 for finished articles and μ_Σ < 50 for tubular semifinished articles of TREX or SUPERTREX type. At first stage of cold drawing μ <2.0. After this final annealing is conducted at temperature of existence of alpha-zirconium with μ = S_b.c/S_t(S_b.c being cross- section area of billet for rolling; S_t being cross-section area of rolled tube; μ_Σ= S_in.b,c/S_f.bic being cross-section area of billet for first rolling; S_in.b,c being cross-section area of finished tube after final rolling. Then billet is brought to finished article. In accordance with second version hardening of tubular billet at specified temperatures, machining and tempering are additionally conducted after hot formation. EFFECT: improved quality of articles by creation of deformation conditions without break of continuity of material of zirconium articles, enhanced technical and economic indices of their manufacture thanks to increased size of initial billets and improved quality of tubular semi-finished articles, obtainment of homogeneous structure of tubular articles, elimination of defects in process of treatment and increased physical and mechanical properties of alloys. 2 cl, 3 dwg