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Alloy 718 is a Ni-based superalloy commonly used for parts of aircraft engines and power plants where very high demands on high-temperature yield strength, creep and corrosion resistance must be met. Polycrystalline parts such as turbine discs are industrially manufactured via hot-forging followed by solution annealing and dual ageing to form nanoscale γ′ and γ" precipitates. However, through the alternative process of ‘direct ageing’, increased yield strength contributions of ∼10% can be achieved while maintaining sufficient creep resistance. In addition to this so-called ‘direct ageing effect’, the omission of solution annealing between forging and ageing is economically attractive. Therefore, to date, direct ageing is widely implemented in the production of forged aerospace parts. However, the detailed mechanisms behind the direct ageing effect yet remain unclear. We present a correlative microscopy …