Metal Properties and Panel Behavior Flashcards
6 cards from real Paintless Dent Repair practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Metal Properties and Panel Behavior flashcards as text
What is the significance of the 'yield point' of metal in PDR?
Answer: The stress level beyond which metal permanently deforms and cannot return to its original shape
The yield point is the threshold beyond which metal undergoes permanent deformation; PDR works by staying below or near the yield point to allow the metal to return to its original shape.
Why does ultra-high-strength steel (UHSS) present unique challenges for PDR?
Answer: UHSS resists deformation so strongly that it may crack rather than flex during PDR, and some manufacturers prohibit PDR on UHSS panels
UHSS is engineered for maximum structural rigidity and may crack rather than flex during PDR attempts; manufacturers often specify that UHSS panels must be replaced, not repaired.
What role does the steel's 'grain structure' play in PDR?
Answer: Metal is stamped during manufacturing in ways that align grain structure, affecting how the panel responds to directional pushing in PDR
Manufacturing stamping aligns the metal's grain structure, and technicians who understand grain direction can apply pressure in ways that work with the grain for more effective repairs.
How does 'springback' affect PDR technique?
Answer: Springback is the metal's tendency to partially return from an overpushed position, which technicians must account for when deciding how far to push
Springback is the elastic return of metal after pressure is released; technicians must account for it by sometimes pushing slightly beyond target level knowing the metal will spring back to the correct height.
What is 'metal fatigue' and when does it become a concern in PDR?
Answer: The weakening of metal through repeated stress cycles that can cause cracking if a dented area is worked too aggressively or repeatedly
Metal fatigue occurs when metal is subjected to repeated stress cycles and weakens progressively; over-working a dent area during PDR can induce fatigue and risk cracking the panel.
Why do newer vehicle panels made with advanced composites present different challenges than traditional steel for PDR?
Answer: Composite materials do not have the same elastic memory as steel, making PDR techniques ineffective or inapplicable on them
Composite and fiber-reinforced plastic panels lack the metallic elastic memory that PDR exploits, making traditional PDR techniques ineffective and requiring different repair methods.