Grain refinement and superplasticity of pipes processed by high-pressure sliding

• Published in: Materials science and technology Vol. 36; no. 7; pp. 877 - 886
• Main Authors: Tang, Yongpeng, Matsuda, Koki, Takizawa, Yoichi, Yumoto, Manabu, Otagiri, Yoshiharu, Horita, Zenji
• Format: Journal Article
• Language: English
• Published: London, England Taylor & Francis 02.05.2020; SAGE Publications
• Subjects: Al alloy; grain refinement; Multi-pass high-pressure sliding; pipe; superplasticity; Multi-pass high-pressure sliding; grain refinement; pipe; Al alloy; superplasticity
• ISSN: 0267-0836; 1743-2847
• DOI: 10.1080/02670836.2020.1746538

The high-pressure sliding (HPS) process was applied for grain refinement of a pipe form of an Al-3wt%Mg-0.2wt%Sc alloy by developing two types of straining techniques (called in this study anvil sliding and mandrel sliding). To achieve a homogeneous microstructure throughout the cross-section of the pipe, the sample is rotated around the longitudinal axis every after sliding operation by introducing multi-pass technique, named multi-pass HPS (MP-HPS) as developed earlier for rods. The MP-HPS-processed sample shows ultrafine-grained structures with an average grain size of ∼260 and ∼300 nm after the HPS processing using anvil sliding and mandrel sliding. The samples also exhibit superplasticity with total elongations well more than 400%, respectively. A finite-element method is used to simulate the evolution of strain in the HPS processing and demonstrates that the simulation well represents the experimental results.