Continuous Precipitation 上游充通大兽 SHANGHAI JIAO TONG UNIVERSITY GP Zones(G.P.区) The first precipitate to nucleate is coherent Copper-rich GP zones Detected by Guinier and Preston independently by XRD in 1938 Fully coherent with the matrix>Very low interfacial energy Minimize the strain energy by choosing a disc-shape perpendicular to the elastically soft <100>directions in the fcc matrix ⊕ Zones are about 2 atomic layer thick and 10 nm in diameter with a spacing of ~10 nm 230列 9e9 G UNIV OAl●Cu X720000 Section through a GP zone parallel to the (200)plane K.Chen 7K. Chen Continuous Precipitation 7 GP Zones (G.P. 区) The first precipitate to nucleate is coherent Copper-rich GP zones Detected by Guinier and Preston independently by XRD in 1938 Fully coherent with the matrix  Very low interfacial energy Minimize the strain energy by choosing a disc-shape perpendicular to the elastically soft <100> directions in the fcc matrix Zones are about 2 atomic layer thick and 10 nm in diameter with a spacing of ~10 nm X 720000