Engineering Board Exam Reviewer · Engineering Materials · medium

Precipitation (age) hardening is commonly used to strengthen:

1. Pure copper
2. Gray cast iron
3. Low-carbon steel only
4. Aluminum alloys such as 2024 and 6061

Answer

D. Aluminum alloys such as 2024 and 6061

Solution

Solution treatment, quenching, then aging forms fine precipitates that block dislocations.

More Engineering Materials questions

1. The heat treatment that restores the ductility of a cold-worked metal by forming new strain-free grains is called:
2. Strengthening a metal by plastic deformation at room temperature is called:
3. Prolonged heating of pearlitic steel just below the eutectoid temperature produces a very soft structure called:
4. Isothermal transformation of austenite at temperatures between those forming pearlite and martensite produces:
5. The ability of a steel to be hardened to a depth by quenching is called:
6. The diagram that shows the time needed for austenite to transform at a constant temperature is the:
7. Reheating quenched (martensitic) steel to a temperature below the eutectoid temperature to reduce brittleness is called:
8. Rapid cooling of steel from the austenite region in water, oil or brine is called:
9. Heating steel into the austenite region and cooling it in still air is called:
10. Heating steel into the austenite region and cooling it slowly in the furnace is called:

All Engineering Materials Reviewer questions