10 Engineering Material Selection Free Online FlashCards

Why is there no universally best engineering material?

There is no universally best material. The right choice meets the required function and essential limits while balancing manufacturability, cost, risk, and environmental impact.

What is a constraint in material selection?

Constraints are mandatory requirements a candidate must meet, such as a maximum mass, minimum strength, operating temperature, corrosion resistance, or service life.

Why must a material be considered in its specific condition?

Properties depend on factors such as alloy, heat treatment, processing route, material direction, temperature, and manufacturing defects.

Why should material and manufacturing process be selected together?

Material and process selection must be considered together: a material may be difficult or uneconomic to form, join, machine, or inspect, while a process can limit material choices or change properties.

What extra requirement applies if a tie rod must resist yielding?

The material must meet both the stiffness requirement and the tensile-strength limit; a favorable stiffness-to-density ratio alone is not enough.

What should be made visible when using weighted scoring?

Weighted scoring rates feasible candidates against agreed criteria and applies importance weights. The scores and weights should be visible because the ranking reflects chosen priorities, not an objective fact.

Which stages does life-cycle assessment consider?

Life-cycle assessment considers impacts from raw-material acquisition through manufacture, transport, installation, use, and end of life.

How should alternatives be compared for life-cycle impacts?

Compare alternatives on the same functional basis, such as the impact of providing a required service for a specified number of years.

Why may a low-impact material per kilogram not reduce product impact?

A lower-impact material per kilogram may not produce a lower-impact product if more material is needed or the product must be replaced more often.

What should be validated before releasing a material choice?

Validate that the chosen grade is available, the process can achieve required dimensions and properties, joining and inspection are viable, and the design remains safe under realistic variation. Testing or prototypes may be needed.

What is an objective in material selection?

Objectives are qualities to improve, such as minimizing cost or mass, or maximizing stiffness.

What are free variables in a material-selection problem?

Free variables are design choices that can be changed, such as material, shape, dimensions, manufacturing process, or surface treatment.