Hot deformation characteristic and microstructural evolution of a near alpha alloy Ti-8Al-1Mo-1V

Document Type : Original Article

Authors

• fateme Zarghani ¹
• Gholamreza Ebrahimi ²
• Amir Momeni ³
• hamid reza Ezatpour ⁴

¹ Department of Materials and Polymer Engineering, Hakim Sabzevari University, Sabzevar, Iran

² -Materials and Metallurgical Engineering Department, Ferdowsi University of Mashhad, Mashhad, Iran

³ Materials Science and Engineering Department, Hamedan University of Technology, Hamedan, Iran

⁴ Department of Engineering Sciences, Hakim Sabzevari University, Sabzevar, Iran

10.22067/jmme.2023.80724.1100

Abstract

Titanium alloy grade Ti–8Al-1Mo-1V (Ti-811) has been widely applied for many applications such as aerospace, automotive and military industries due to their high specific strength, low density, and excellent corrosion resistance. In this work, cylindrical specimens with a height of 12 mm and diameter of 8 mm were machined for the hot compression tests. the flow stress behavior of near-α alloy Ti-811 was investigated by hot compression testing under conditions of varying temperature (between 950, 975, 1000, 1025, 1050 and 1075 ◦C), strain rates ( 0.001, 0.01, 0.1 and 1s-1) and true strain up to 0. 6. The stress–strain curves of Ti-811 alloy revealed that the continuous flow softening occurs, anyway, the flow softening amount show greater flow softening in the two phase region as compared to the single phase region. Mechanical testing

and optical microscopy analyses indicate that dynamic recrystallization occurred, for single-phase β microstructure. However; a broad variety of microstructure formation mechanisms including allotropic phase transformations, platelet kinking and globularization occurred for two- phase α + β region.

Keywords

• Near- &alpha
• alloy Ti-811
• Hot compression
• Dynamic recrystallization
• globularization

Main Subjects

• Metal Forming

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