Inspection of Composites (unfinished)

When inspecting composites, what should you inspect for? (3)

• Delamination

• Debonding of skin from core

• Moisture

• Corrosion

What NDI method can you use for composites?

• Ultrasonic

• Acoustic emission

• Radiographic

Which is the simplest inspection method for composites?

Tap test

Which inspection is the newest?

Thermography

What is tap testing?

Quick surface-level evaluation

What does tap testing look for? (2)

• Delamination

• Debonding

When taping a surface, what can you use?

• Light hammer (2 oz max)

• Coin

When tap testing and a ring sound is heard, what can be inferred?

Good area

When performing a tap test and a flat/dead soun is heard, what can be inferred?

Potential problem area

What is tap testing effective for?

Skins less than 0.080’ thick

When tap testing a honeycomb structure, how must you test?

Test both sides

Are composite structures inherently conductive?

No

What must high-speed/high-performance jet add?

Conductivity

What are two material that can add conductivity to composites?

• Aluminum

• Copper

What is aluminum for? (2)

• Fiberglass

• Kevlar

What is copper for?

Carbon fiber

How can you check continuity?

Ohmmeter

What does thermography use?

Radiant electromagnetic heat

What does thermography detect?

• Disbond or delamination

• Cracks

• Impact damage

• Panel thinning

• Water ingress

Does visual appearance of welds guarantee weld quality?

No

What are 3 good weld characteristics?

• Uniform width

• Even ripples

• Good penetration

What is the most important factor of penetration weld?

Depth of fusion

What are the two influences of penetration?

• Thickness of base material

• Filler rod size

What are 4 traits of incorrect welds?

• Long, pointed ripples

• Gas pockets

• Porosity

• Slag inclusion