Materials Science in Automotive Flashcards
7 cards from real CAE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Materials Science in Automotive flashcards as text
Which welding process is most commonly used for joining aluminum body panels in automotive manufacturing due to its ability to avoid porosity?
Answer: Friction Stir Welding (FSW)
Friction stir welding is a solid-state process that avoids melting aluminum, eliminating hydrogen porosity and achieving high-quality joints.
What is the glass transition temperature (Tg) significance for polymer-based automotive interior components?
Answer: Above Tg, the polymer transitions from glassy to leathery/rubbery behavior
Above Tg, amorphous polymer chains gain mobility, causing the material to soften from a rigid glassy state to a rubbery or leathery state.
In galvanic corrosion between automotive components, which pairing is most likely to accelerate corrosion of the anodic material?
Answer: Aluminum fastener in contact with titanium structure in saline environment
Aluminum (more anodic) coupled with titanium (noble) in an electrolyte creates a large galvanic potential driving rapid aluminum dissolution.
Which microstructural feature in dual-phase (DP) steel provides the high work hardening rate desirable in automotive crash structures?
Answer: Continuous ferrite matrix with islands of martensite
Martensite islands in a soft ferrite matrix create back-stress during deformation, producing a high initial work hardening rate that improves energy absorption.
What is the primary advantage of using carbon fiber reinforced polymer (CFRP) in automotive chassis applications?
Answer: Specific stiffness (E/ρ) up to 5× higher than steel
CFRP has a Young's modulus comparable to steel (~70–150 GPa) at a density of ~1.6 g/cm³, yielding specific stiffness far exceeding metals.
Which non-destructive evaluation (NDE) technique is most effective for detecting delaminations in CFRP automotive body panels?
Answer: Phased array ultrasonic testing (PAUT)
PAUT uses electronically steered ultrasonic beams to detect planar defects like delaminations that are parallel to the panel surface and invisible to X-rays.
Which stainless steel series is preferred for automotive exhaust systems due to its oxidation resistance at elevated temperatures?
Answer: 400 series ferritic
Ferritic grades (409, 439) offer adequate oxidation resistance up to ~900°C, good thermal fatigue life, and lower cost than austenitic grades for exhaust applications.