The metallography and deformation of the aligned Cd-Zn eutectic

Abstract

The tensile deformation of the aligned Cd-Zn eutectic alloy has been investigated with particular attention paid to the influence of interlamellar spacing (λ). These tests were supplemented by optical and transmission electron metallography. At plastic strains of 10⁻⁶ the stress was independent ofλ, at 10⁻⁵ the stress increased with decreasingλ and by 10⁻⁴ twinning had become the dominant deformation mode. Twinning stress was found to increase with decreasing cell or grain size, rather than being a function ofλ. Electron microscopy demonstrated that individual twins were continuous through many lamellae of each phase. Differences between tension and compression tests are examined and possible reasons based on dislocation mechanics are discussed.