摘要
用X射线衍射仪、光学显微镜和拉伸试验等研究了退火温度(Ta)对Ti-50Ni和Ti-45Ni-5Cu形状记忆合金丝相组成、显微组织和拉伸性能的影响。结果表明,退火态Ti-50Ni和Ti-45Ni-5Cu合金丝室温组成相均为单斜结构的马氏体B19′和CsCl型结构的母相B2。350~550℃退火态Ti-50Ni和Ti-45Ni-5Cu合金丝皆处于回复阶段,组织呈现纤维状,600~700℃退火态合金丝处于晶粒长大阶段,组织呈等轴状;两种合金的再结晶温度均在550~600℃之间。Ti-50Ni和Ti-45Ni-5Cu合金丝的抗拉强度(Rm)和马氏体再取向平台长度(LM)相近,Ti-50Ni合金丝的马氏体再取向应力(σM)和伸长率(A)大于Ti-45Ni-5Cu合金丝。随Ta升高,两种合金丝的Rm和LM下降,A升高,σM先下降后上升,Ti-50Ni合金丝σM的最小值102.8 MPa在450~500℃退火态合金丝中取得,Ti-45Ni-5Cu合金丝σM的最小值63.3 MPa在400℃退火态合金丝中取得。
Effects of annealing temperature(Ta) on phase composition, microstructure and tensile properties of Ti-50 Ni and Ti-45 Ni-5 Cu shape memory alloy wires were investigated by means of X-ray diffractometer, optical microscope and tensile test. The results show that the phase compositions of the annealed Ti-50 Ni and Ti-45 Ni-5 Cu alloy wires at room temperature are monoclinic martensite B19′ phase and CsCl type parent phase B2. The Ti-50 Ni and Ti-45 Ni-5 Cu alloy wires annealed at 350-550 ℃ are in the recovery stage and the microstructure morphology is fibrous, and the alloy wires annealed at 600-700 ℃ are in the grain growth stage and the microstructure morphology is equiaxed, and the recrystallization temperature of the two alloys is between 550 ℃-600 ℃. The tensile strength(Rm) and martensite reorientation platform length(LM) of the Ti-50 Ni and Ti-45 Ni-5 Cu alloy wires are similar, and the martensite reorientation stress(σM) and elongation(A) of the Ti-50 Ni alloy wire are larger than that of the Ti-45 Ni-5 Cu alloy wire. With the increase of Ta, the Rm and LM of the two alloys decrease, the A increases, and the σM decreases first and then increases. The minimum value of σM of the Ti-50 Ni alloy wire annealed at 450-500 ℃ is 102.8 MPa, and the minimum value of σM of the Ti-45 Ni-5 Cu alloy wire annealed at 400 ℃ is 63.3 MPa.
作者
张坤刚
贺志荣
叶俊杰
杜雨青
ZHANG Kun-gang;HE Zhi-rong;YE Jun-jie;DU Yu-qing(School of Materials Science and Engineering,Shaanxi University of Technology,Hanzhong 723001,China)
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2021年第5期43-49,共7页
Transactions of Materials and Heat Treatment
基金
国家重点研发计划(2016YFE0111400)
陕西理工大学研究生创新基金(SLGYCX2122)。
