High-strength Steel For Automobiles

GNEE New Material automotive steel

The core of modern automobile manufacturing is safety and environmental protection, and the body requires "increasing strength and reducing weight". Advanced high-strength steels are booming in this context and are widely used in structural and safety parts of automobile bodies.

 

Types of high-strength steels used in automobiles

1. DP steel, duplex steel

2. CP steel, complex phase steel

3. TRIP steel, phase transformation-induced plasticity steel

4. MS steel, martensitic steel

5. QP steel, quenched and partition steel

6. TWIP steel, twin induced plasticity steel

7. PH steel or B steel, stamping hardening/boron steel

DP steel

Characteristics: no yield elongation, no aging at room temperature, low yield ratio, high work hardening index, high bake hardening value.

Application: DP series high-strength steel is the preferred steel for structural parts, which is widely used in structural parts, reinforcements and anti-collision parts. For example, underbody beams, rails, crash bars, crash bar reinforcement structures, etc.

Chia Tai Steel

Features: fine grains, high tensile strength. The yield strength is significantly higher than that of duplex steels with the same tensile strength. It has good bending performance, high hole expansion performance, high energy absorption capacity and excellent flanging forming performance.

Applications: Chassis suspensions, B-pillars, bumpers, seat rails, etc.

TRIP Steel

Characteristics: Contains residual austenite in the tissue, with good formability. During the forming process, the residual austenite gradually transforms into hard martensite, which is conducive to uniform deformation. TRIP steel also has the characteristics of high impact absorption energy, high strength of plastic products, and high n-value.

Application: parts with complex structure, such as B-pillar stiffeners, front longitudinal beams, etc.

MS steel

Characteristics: High yield ratio, high tensile strength, relatively low elongation need to pay attention to the tendency to delay cracking. It has the characteristics of high impact absorption energy, high strength of plastic products and high n value.

Application: Cold stamping and cross-section of simple parts are relatively single roll-formed parts, such as bumpers, sill stiffeners, crash bars in side doors.

QP steel

Characteristics: With martensite as the matrix phase, the TRIP effect of residual austenite during deformation can achieve higher work hardening ability, so it has higher plasticity and formability than ultra-high-strength steels of the same grade.

Application: It is suitable for automotive safety parts and structural parts with complex shapes, such as A, B pillar reinforcements.

PH steel or B steel

Characteristics: ultra-high strength (tensile strength above 1500MPa), effectively improve crash performance, lightweight body; The shape of the parts is complex and the formability is good; High dimensional accuracy.

Application: Safety structural parts, such as: front and rear bumpers, A-pillar, B-pillar, middle channel, etc.

TWIP steel

Features: TWIP steel is a kind of all-austenitic steel with high C, high Mn and high Al composition. With the dynamic refinement caused by the twin, a very high work hardening capacity can be obtained. TWIP steel has ultra-high strength and ultra-high plasticity, and the strength plastic products can reach more than 50GPa%.

Application: TWIP steel has very superior formability and ultra-high strength, and is suitable for parts that require high tensile and swelling properties of materials, such as automotive safety parts and structural parts with complex shapes.