Patterning Alloy Precipitates through Tailored Surface Loading.

An innovative processing technique that produces distinct, locally patterned microstructures within a single sample is introduced in this article. This technique alters the conventional heat-treatment process by applying a micropatterned external surface load to selected locations during the quench and anneal. In the aluminum-copper system (2 wt pct Cu), spatial control of AlCu precipitates within 50 μm features over an aggregate length scale of millimeters is achieved. Chemical interactions among the furnace environment, the alloy sample, and the loading device can affect the experiments adversely and steps used to ameliorate these effects are discussed. The precipitate patterning technique presented in this article is compatible with standard 'heat and beat' processing and could be used potentially to develop new multifunctional metallic alloys. [ABSTRACT FROM AUTHOR]