NbRu系高温记忆合金的显微组织与界面结构

NbRu and TaRu based alloy are up to date the shape memory materials with the highest transformation temperature. In this study, the microstructure and.interface structure, phase transformation, mechanical properties and shape memory.effects of NbRu, NbRuFe and TaRu alloys were investigated. It was found that.two-step phase transformation of CsCl()△face-centered tetragonal(‖)△.monoclinic僴(‖‖) occurs during cooling NbRu based alloy and TaRu alloys from high.temperature to room temperature. The crystal structure of the martensite at room temperature is monoclinic, with the lattice parameters increasing with the content of Ru. The martensite variants exhibit self-accommodating morphology for NbRu and TaRu alloy. The twinning relationship between the substructural bands is (101) Type I mode, and this kind of twinning boundary is straight. The martensite variants are pseudotwin related, with a wavy boundary. The bending fracture of how brittle fracture surface. Reorientation and coalescence of.martensite variants and dislocation slip happen during the deformation of NbRu.alloys. The ‖. reverse martensitic transformation contributes dominantly to the shape memory strain, with the 〔.‖ reverse transformation as an auxiliary. When the compression prestrain is higher than 3%, with the increase of the total prestrain, the residual strain increases. The addition of Fe to the NbRu alloy has no significant effect on the phase transformations and microstructures.

结合相变晶体学分析探讨nbru系合金具高温度和人体恢复应变的复制原因，为新高温记忆合金的研制奠定理论基础。...