Aging Mechanisms
1. Your friend has a new job as mechanical engineer helping design bridges. He designs his main support beam to support for a cross sectional area of 100 inA2, made from a Al-4% Cu alloy, treated to produce the highest strength. During production, a power outage occurs, and the furnace shuts down for 2 hours before heating back to the aging temperature of 260 C. What is the resulting impact on the number of people that can stand on the bridge (assuming average weight of 200 lbs per person)? How is this changed if the aging temperature was 150 C? How does your friend adjust the design to use this material and still meet the original load requirements? (hint: use figure 12-12)
