Work

Phase Equilibria of the Cu-Sn-Ti Ternary System at 450 °C

Year: 2026

Type: article

Abstract: C1990HP is a kind of commercial Cu alloy containing 3.5 wt.% Ti. It has unique mechanical and physical properties. Thus, C1990HP is regarded as a highly promising lead-frame material in electronic packaging. Sn is a base element used for lead-free solders. The knowledge of the Cu-Sn-Ti phase equilibrium plays a crucial role in understanding the interfacial reactions between C1990HP and Sn-based solders, however the phase equilibria information of this system is still lacking. The isothermal section of the Cu-Sn-Ti ternary system at 450 °C was experimentally determined. The phase equilibrium results confirmed the existence of two kinds of ternary compounds τ 1 -CuSnTi and τ 2 -CuSn 3 Ti 5 , which are only stable within a narrow composition range. No additional ternary compounds were found. Moreover, the Sn 3 Ti 5 and Sn 5 Ti 6 binary phases have considerable solubility of Cu. Meanwhile, the isothermal section was found to contain 17 three-phase regions, 33 two-phase regions and 17 single-phase regions.

Source: Journal of Phase Equilibria and Diffusion

DOI: 10.1007/s11669-026-01237-3

Authors: Hao-Wei Lee, Yen-Ling Chen, Mark Ming-Cheng Cheng, Wei-chen Kung, Hsien-Ming Hsiao, Yee-Wen Yen

Institutions: National Taiwan University of Science and Technology, Indiana University Indianapolis, National Atomic Research Institute

Language: English

Topic: Metallurgical and Alloy Processes

Subfield: General Materials Science

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,890

Funder: National Taiwan University of Science and Technology