Abstract
The effects of prior cold work on hardness, tensile properties, electrical conductivity and microstructure of an aged Cu–1.5 wt% Ti alloy have been studied by employing hardness and resistivity measurements, tensile tests and scanning and transmission electron microscopy. The hardness increased from 80 VHN in the solution-treated condition, to 210 VHN on peak ageing and 280 VHN with prior cold work followed by ageing. While a similar trend has been observed in yield and tensile strengths, the ductility (percentage elongation) decreased from 45% to 9%. The electrical conductivity of the alloy also increased up to 26% International annealed copper standard upon ageing the cold-worked alloy. Maximum strengthening of the alloy was associated with the precipitation of metastable, coherent and ordered Cu4 Ti, β′ phase having body-centred tetragonal structure. The differences in the properties and microstructural evolution between low and high titanium alloys (for example, the absence of composition modulations and deformation twins in Cu–1.5 Ti alloy, while they are present in Cu–4.5 Ti alloy) have been discussed. Prior cold work did not change the fracture mode of microvoid coalescence.
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NAGARJUNA, S., BALASUBRAMANIAN, K. & SARMA, D.S. Effect of prior cold work on mechanical properties and structure of an age-hardened Cu–1.5wt% Ti alloy. Journal of Materials Science 32, 3375–3385 (1997). https://doi.org/10.1023/A:1018608430443
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DOI: https://doi.org/10.1023/A:1018608430443