1.What are the requirements and locations for galvanized steel strip to be used in car body panels?Door panels/hoods/fenders
Requirements: high surface quality (Class A surface), dent resistance, formability
Galvanizing type: pure zinc coating (GI): thickness 60-90g/m² (double-sided), providing basic corrosion protection
Zinc-iron alloy coating (GA): alloyed, higher hardness, anti-powdering, suitable for complex stamping
Roof/side panels
Challenges: Large-size panels require high dimensional stability
Process optimization: Use high R-value substrates to reduce stamping rebound
2.What are the specific parts of the car body structure where galvanized strip steel is used?
Longitudinal beam/crossbeam/column
Core requirement: collision energy absorption (high tensile strength + ductility)
Seat frame/seat belt fixing plate
Safety requirement: fatigue strength > 500MPa
Special process: laser welding galvanized sheet (TWB) to reduce the number of parts
3.Where is galvanized steel strip used in chassis system?
Subframe/control arm
Anti-corrosion level: Need to pass 1000h salt spray test
Coating upgrade: thick zinc layer (Z180-Z250) + passivation treatment (Cr-free)
Fuel tank/exhaust system
Heat resistance requirements: Exhaust pipe uses galvanized aluminum, temperature resistance 600℃
Anti-corrosion design: The inner wall of the fuel tank is electro-galvanized, and the outer wall is hot-dip galvanized
4.What are the exclusive applications of galvanized strip steel in new energy vehicles?
Battery pack shell
Key indicators: ■ Conductivity (resistance < 0.1Ω·m) ■ Electromagnetic shielding (> 60dB attenuation)
Material innovation: ■ Galvanized steel plate + conductive coating (such as nickel-based coating) ■ Seam welding and sealing after stamping, IP67 protection
Motor bracket ◦ Vibration reduction requirements: Use high damping galvanized composite plate (zinc layer + viscoelastic resin layer)
5.What are the current industry technology trends?
Combination of lightweight and high-strength steel
Application of 1200MPa grade galvanized martensitic steel (MS+Z), 20% weight reduction
Green coating technology
Chromium-free passivation (silane/zirconium treatment) + bio-based anti-rust oil
Intelligent surface detection
Online laser scanning of coating defects (resolution 1μm)