Program to Develop High Strength Aluminum Powder Metallurgy Products. Phase 1. Process Optimization

Aluminum-based P/M hand forgings and extrusions in two Al-Zn-Mg-Cu alloys have been studied to evaluate the effects of powder processing variations on forging quality and properties and extrusion properties. High quality hand forgings with high strength and ductility have been produced directly from hot pressed aluminum powder compacts without an intermediate extrusion operation. The processing conditions leading to maximized hand forging properties are: Cold press to at least 70% green density; preheat 1 hour at 1,000 F in dry argon; hot press at 90 ksi; forge at a temperature appropriate for the specific alloy; forge by any standard hand forging press technique with as much total reduction as possible.