TA6钛合金板材换向轧制工艺研究

Study on Alternative Rolling Process of TA6 Titanium Alloy Sheet

通过设计两种换向轧制工艺,采用2 800 mm四辊可逆热轧机成功制备了满足GJB 2505A—2008标准要求的3.5 mm厚TA6钛合金薄板,并研究了轧制工艺对TA6钛合金板材显微组织和力学性能的影响。研究结果表明:采用这两种不同轧制工艺轧制TA6钛合金板材,当总变形量为72%时,板材内部均为混乱的魏氏组织,且组织均匀性差,纵横向抗拉强度差值大于50 MPa;随着变形量增大,组织不断细化,强度不断提高,当变形量达到89%以上时,与B工艺相比,采用A工艺得到的板材组织均匀性更好,且纵横向抗拉强度差值小于20 MPa。采用A工艺制备的TA6钛合金板材退火后为细小均匀的再结晶组织,且力学性能满足GJB 2505A—2008标准要求。

TA6 titanium alloy sheets with thickness of 3.5 mm had been produced by the 2.8-meter high reversible hot mill, the effects of alternative rolling process on microstrueture and mechanical properties of TA6 titanium alloy sheets were studied in this paper. The results indicate that under 72% deformation the microstructure is the disorderd widmanstatten structure, and the tensile strength difference between transverse and longitudinal is more than 50 MPa; with the increasing of deformation, the structure is refined and the strength is improved, while the total deformation is up to 89% or more, the process A is better for the uniformity of the sheet compare to process B, the tensile strength difference between transverse and longitudinal is less than 20 MPa. The annealed recrystallization microstructure of TA6 titanium alloy sheet is tiny and uniform prepared by the process A, and mechanical properties can meet the requirement of GJB 2505A-2008.