A new insight into high-strength Ti62Nb12.2Fe13.6Co6.4Al5.8 alloys with bimodal microstructure fabricated by semi-solid sintering

L H Liu; C Yang; L M Kang; S G Qu; X Q Li; W W Zhang; W P Chen; Y Y Li; P J Li; L C Zhang

doi:10.1038/srep23467

A new insight into high-strength Ti62Nb12.2Fe13.6Co6.4Al5.8 alloys with bimodal microstructure fabricated by semi-solid sintering

Sci Rep. 2016 Mar 31:6:23467. doi: 10.1038/srep23467.

Authors

L H Liu¹, C Yang², L M Kang², S G Qu², X Q Li², W W Zhang², W P Chen², Y Y Li², P J Li¹, L C Zhang³

Affiliations

¹ Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China.
² National Engineering Research Center of Near-net-shape Forming for Metallic Materials, South China University of Technology, Guangzhou 510640, China.
³ School of Engineering, Edith Cowan University, 270 Joondalup Drive, Joondalup, Perth, WA 6027, Australia.

Abstract

It is well known that semi-solid forming could only obtain coarse-grained microstructure in a few alloy systems with a low melting point, such as aluminum and magnesium alloys. This work presents that semi-solid forming could also produce novel bimodal microstructure composed of nanostructured matrix and micro-sized (CoFe)Ti2 twins in a titanium alloy, Ti62Nb12.2Fe13.6Co6.4Al5.8. The semi-solid sintering induced by eutectic transformation to form a bimodal microstructure in Ti62Nb12.2Fe13.6Co6.4Al5.8 alloy is a fundamentally different approach from other known methods. The fabricated alloy exhibits high yield strength of 1790 MPa and plastic strain of 15.5%. The novel idea provides a new insight into obtaining nano-grain or bimodal microstructure in alloy systems with high melting point by semi-solid forming and into fabricating high-performance metallic alloys in structural applications.

Publication types

Research Support, Non-U.S. Gov't