Annealing Treatment and Basketweave Structure Deformation Mechanism of Laser Deposition Manufactured TA15 Titanium Alloy

作者：Yang Guang^*; Wang Wendong; Qin Lanyun; Ren Yuhang; Li Changfu; Wang Wei

来源：Rare Metal Materials and Engineering, 2017, 46(7): 1935-1942.

• laser deposition manufacturing
• alpha plus beta phase zone
• annealing treatment
• microstructure
• mechanical properties

TA15 titanium alloy bulk specimens were prepared by laser deposition manufacturing with spherical TA15 powder as starting material. The effects of alpha+beta phase zone annealing treatment on microstructure and mechanical properties of laser deposition manufactured TA15 titanium alloy were studied by optical microstructure (OM) and scanning electron microscopy (SEM). Furthermore, the lamellar deformation mechanism was also discussed. The results indicate that microstructure is basketweave structure or near basketweave structure after alpha+beta phase zone annealing treatment; pattern and size of a phase is affected effectively by annealing temperature. The mechanical properties after annealing still show the anisotropy in different directions: the strength is low and the plasticity is high in deposition direction while the strength is high and the plasticity is low in vertical deposition direction. The interlayer binding zone slip deformation plays a vanguard role and the columnar crystal grain boundary has a bound effect on a phase slip deformation. Microhardness is affected by the amount of a phase while it changes little with the increase of annealing temperature. a lamellar in basketweave structure under the stress changes from near orthogonal to near parallel to the direction of stress, and staggered arrangement of a lamellar generates resistance between each other when it is in the state of slip deformation. Both deposition direction and vertical deposition direction have same tensile fracture modes which is ductile fracture after alpha+beta phase zone annealing treatment.

• 出版日期2017-7
• 单位沈阳航空航天大学