When to use which material

Each material used in FRC has distinct mechanical and manufacturing properties that determine how it behaves under load, during machining, and in real-world robot use.

6061-T6 Aluminum

High strength and stiffness

Excellent machinability

Holds tapped threads well

Maintains shape under load with minimal flex

Can be anodized for corrosion resistance

5052 Aluminum

High ductility (bends without cracking easily)

Lower strength than 6061-T6 in rigid structures

Very good fatigue resistance in sheet form

Poor thread-holding capability compared to 6061

Excellent for forming and sheet fabrication

Polycarbonate

Extremely high impact resistance (does not shatter)

Flexible and can bend significantly before failure

Transparent, allowing visibility through panels

Sensitive to heat during machining

Crack-resistant compared to brittle plastics like acrylic

SRPP (Glass-Filled Polypropylene)

Lightweight with moderate stiffness

High vibration damping compared to metals

More rigid than standard plastics due to glass fill

Low density relative to aluminum

Good fatigue resistance in sheet applications

Steel

Very high strength and hardness

Excellent wear resistance

High density (heavy compared to aluminum)

Maintains shape under extreme loads

Can be heat-treated for increased hardness

Plywood

Cross-laminated structure resists splitting

Good stiffness for its weight

Anisotropic (strength depends on grain direction)

Absorbs impact energy without immediate fracture

Sensitive to moisture and environmental conditions

Key Idea

Each material behaves differently under stress, machining, and impact. Understanding these unique properties allows FRC teams to choose the right material for strength, weight, flexibility, and durability requirements.