DC07 Cold Rolled Steel Coil

Nature Steel's DC07 Cold Rolled Steel Coil is made from high-quality ultra-low carbon hot-rolled coils. It is smelted in an oxygen converter and refined with alloying elements such as titanium (Ti). It is then processed through precision cold rolling and multi-pass continuous annealing. The microstructure consists of uniform and fine ferrite grains. It has an extremely high plastic strain ratio (r value ≥ 2.5) and work hardening index (n value ≥ 0.23). The carbon content is as low as ≤ 0.01%. It can withstand extreme plastic deformation and multi-pass tensile testing without cracking or wrinkling. The surface is smooth and flawless. It can be directly used for processing complex automotive parts without additional polishing. It is the core preferred material for high-end automotive exterior body panels and complex structural parts. At the same time, it is suitable for the stringent forming requirements of high-end home appliances, precision instruments and other fields.

Core Parameter Specifications

Automotive Complex Component Application Scenarios

Nature Steel's DC07 Cold Rolled Steel Coil is specifically designed for high-end automotive complex components. Its core application scenarios cover automotive interior and exterior trim and structural parts, making it particularly suitable for high-end components with complex shapes, high aesthetic requirements, and significant molding challenges. Specific applications are as follows: Automotive exterior body panels: Door panels, hood panels, trunk lid panels, fenders, etc., requiring ultra-deep drawing with flawless surfaces and a smooth, even finish after painting. DC07's ultra-low yield strength and FD-grade surface properties are a perfect fit, showcasing a high-end automotive feel. It also supports subsequent galvanizing and aluminized zinc plating to enhance corrosion resistance.

Complex automotive interior parts: Instrument panel housings, complex curved surfaces of the center console, door trim panels, seat supports, etc., requiring high forming difficulty and dimensional accuracy. DC07's high plasticity and dimensional accuracy can precisely match the processing needs of complex structures, eliminating the need for secondary grinding after processing and improving production efficiency.

Complex automotive structural parts: Fuel tank housings, complex chassis supports, gearbox housings, steering system components, etc., needing to withstand complex stresses. DC07's stable mechanical properties and resistance to deformation ensure component reliability and improve vehicle safety. Its excellent weldability reduces the risk of welding cracks.

Specialized parts for new energy vehicles: Battery casings, battery trays, charging port brackets, etc. for new energy vehicles require high precision, high formability, and lightweight. DC07's ultra-deep drawing performance and thin-gauge advantages can meet the stringent standards of new energy vehicle components, helping to upgrade the vehicle's lightweight design.

Automotive industry-specific quality testing standards

To meet the stringent requirements of complex automotive components, each batch of DC07 Cold Rolled Steel Coils undergoes a rigorous five-fold testing process exclusive to the automotive industry, ensuring full traceability and providing authoritative test reports. This guarantees that every batch meets automotive production standards. Specific testing items include:

Chemical Composition Testing:
Utilizing a high-precision spectrometer, the content of elements such as C, Mn, P, S, and Ti is accurately measured, strictly adhering to EN10130 standards to ensure ultra-low carbon ratios and alloy element content meet standards, guaranteeing extra-deep drawing performance and structural stability.

Mechanical Property Testing:
Focusing on yield strength, tensile strength, elongation after fracture, r-value, and n-value, ensuring compliance with the forming and stress requirements of complex automotive components and eliminating mechanical property defects. Cupping tests and hole expansion tests are also used to evaluate forming performance.

Surface Quality Testing:
A dual inspection process combining manual inspection and high-precision machine testing rigorously checks for surface scratches, pitting, oxidation, and other defects, ensuring surface quality meets FC/FD grades and is suitable for automotive exterior parts requirements. Surface flatness is also checked to ensure optimal subsequent coating results.

Grain size inspection:
Specialized inspection of micro-grain size ensures uniform and fine grains, guaranteeing material plasticity and deep-drawing performance, and preventing molding cracking caused by uneven grain size.
Dimensional accuracy inspection:
Using precision thickness gauges and laser rangefinders, thickness and width tolerances are precisely controlled to ensure mold dimensions are suitable for complex automotive parts, reducing processing errors and improving component assembly accuracy.