🔍 Key Concepts

• Heat treatment processes such as annealing, normalizing, quenching, and tempering • How heat treatment changes mechanical properties of steel (strength, hardness, ductility) • The relationship between heat treatment and internal stresses and workability (machining)

💭 Think About

• Think about what happens to steel when it is heated and cooled in a controlled way. Which properties can be changed by this process? • Consider whether heat treatment is usually done for just one single purpose or if it can serve multiple benefits at the same time. • Ask yourself: in shipbuilding and repair, why might engineers decide to heat treat a steel component after forming, welding, or machining it?

✅ Before You Answer

• Verify which properties of steel are commonly improved by annealing and tempering (e.g., ductility, toughness). • Check whether residual stresses from welding or forming can be reduced through heat treatment. • Confirm if changing the steel’s structure through heat treatment can make it easier to machine (cut, drill, or shape).