jats:p The effect of cooling rate on the microstructural evolution of Aljats:sub0.5</jats:sub>CrFeCoNiCu has been studied using differential scanning calorimetry and scanning electron microscopy. As cast Aljats:sub0.5</jats:sub>CrFeCoNiCu contained three phases; Cr–Fe–Co–Ni solid solution dendrites, Cu rich interdendritic material and L1jats:sub2</jats:sub> precipitates. During cooling at rates between 10 and 50°C minjats:sup−1</jats:sup>, an additional exothermic event, at ∼1010°C, was observed in the heat flow curves. Microstructural examination after cooling revealed the presence of two distinct populations of intragranular precipitates not present in the as cast material. Energy dispersive X-ray spectroscopy indicated that Cu rich precipitates formed within the dendrites, while a Cr–Fe–Co rich phase formed in the interdendritic constituent. Precipitation during cooling at rates approaching 1°C sjats:sup−1</jats:sup> indicates that the diffusion kinetics of Aljats:sub0.5</jats:sub>CrFeCoNiCu is not, as previously suggested, sluggish. </jats:p>