To make a car, we need many different materials such as steel materials, non-ferrous metals, composite materials, glass, rubber, etc. Among them, steel materials
It is expected to account for
When it comes to 65%-85% of the car’s own weight, no matter it’s the car’s outer shell or its heart, the body of steel material can be seen everywhere.
film.
Automobile steel is mainly divided into two categories:
One is automobile body steel, which constitutes the outer shell and skeleton of the automobile; the other is automobile tire gold structural steel, which constitutes the automobile engine
Machine, transmission
The core material of dynamic system, suspension system, etc. Next, we will give you a detailed introduction.
1. Steel for car body
Let's first look at the steel for automobile bodywork. Load-bearing body, the whole body is one body, steel constitutes his skeleton,
And the engine, transmission system, front and rear suspension and other components
Are assembled on this frame.
1. Steel for outer panel of automobile body
The steel for automobile body outer panels is mainly used to manufacture front, rear, left and right door outer panels, engine hood outer panels, trunk lid outer panels and other parts. It should
Has good formability,
Corrosion resistance, dent resistance and good electric weldability. The outer panel of the car body is mostly coated with a plate to meet the anti-corrosion requirements.
To improve the dent resistance, bake hardened steel, high-strength
IF steel and high formability cold-rolled annealed dual-phase steel (such as DP450). Multi-purpose heat for coated plates
Galvanized sheet, hot-dip galvanized iron sheet, electro-galvanized sheet, electro-galvanized-nickel sheet, etc.
2. Steel for body inner panel
Through the outer panel of the car, we can see that the shape of the parts of the inner panel of the car body is more complicated, which requires the steel for the inner panel of the car body to have
Higher formability and deep drawing performance, so the car
The inner plate of the body is mostly made of IF steel with excellent stamping formability and deep-drawing performance, and a small amount of high-strength IF steel is used.
The plating requirements are similar to those of the outer plate.
3. Automobile body structure
Further inside, we can see the car body structure. It is closely related to the safety and lightweight of automobiles. because
This material selection requires both high strength and high plasticity. First
High-strength steel (AHSS) has good strong plastic bonding and good collision
The characteristics and higher fatigue life are mostly used in body structural parts. For example, it's in
Front and rear bumper frames and key parts such as A-pillar and B-pillar
Has been widely used, in the event of an impact, especially in front and side impact, it can effectively reduce driving
Deformation of the cabin to protect the drivers and passengers
Safety. Advanced automotive high-strength includes dual-phase steel, martensitic steel, phase transformation induced plasticity steel, duplex steel, and quenched ductile steel.
2. Alloy structural steel for automobiles
Knowing the steel used for the outer shell and frame of the car, let's continue to understand the alloy structural steel for the car hidden inside the car body. Mainly include: shaft
Use quenched and tempered steel and non-quenched and tempered
Steel, gear steel, all kinds of steel for bullets and all kinds of steel for high-strength standard parts.
1. Quenched and tempered steel and non-quenched and tempered steel for shafts
In automobiles, various axles play an important role. As long as the car starts to run, they will bear
A lot of stress. The front bearing is subjected to bending fatigue stress, curved bearing
Under the combined stress of bending and torsion, the transmission bearing is subjected to torsional fatigue stress, and the connecting rod bears
Subjected to asymmetrical tension and compression, they should... in order to allow them to work healthily and safely, shafts
Quenched and tempered steel usually contains certain alloying elements to ensure quenching
Permeability (a kind of ability to ensure that the strength of each part of the part cross section meets the requirements of the part), and improve the impact toughness
sex. At present, quenched and tempered steel for crankshaft
There are 40Cr, 42CrMo, etc., automobile half shafts are commonly used in S45C, SCM4, SCM6, SAE1045, etc., and automobile connecting rods are multi-purpose quenched and tempered steel
40Cr, S48C. No
Quenched and tempered steels such as 12Mn2VBS and 35MnVN have also been widely used in steering knuckles and engine connecting rods.
2. Gear steel
Gears are also an important power transmission component on automobiles. The performance requirements of gear steel are: high crush resistance and pitting corrosion resistance
Ability; good impact resistance and bending
Ability; suitable hardenability, depth of hardened layer and core hardness; good process performance and cutting processing
Performance; and deformation and dimensional stability. Gear steel has
SCM420, SCM822 and other Cr-Mo series, Cr-Ni-Mo series and Ni-Mo series.
3. Steel for bullets
Springs are used in automobiles in large quantities and in many varieties. They are a basic structural part. The main uses are elastic steel for suspension and valve spring steel.
, In light or heavy trucks, spring suspension
The dosage of the rack is generally 100-500kg. The performance requirements of spring steel are: high elastic limit and relaxation
Resistance, good hardenability and suitable hardenability, high fracture toughness
Resistance and strain fatigue life, good metallurgical process performance and formability,-
Certain abrasion resistance and corrosion resistance. At present, the steel for suspension springs mainly includes: Si-Mn series, Mn-Cr
Department, Cr-V Department. Mn-Cr-B, etc.
4. Steel for various high-strength standard parts
In recent years, high-strength standard parts have gradually increased in automotive applications. Steel for riveting screws is one of them. It requires
Good process performance, machinability, strength performance
Fatigue performance and delayed fracture ability under high strength.
Commonly used license plates for passenger cars
①HC260B, B180H1, JSC340H, SPFC340H, etc.
②HC700/980DP, HC820/1180DP, MS1500T/1200Y, etc.
③HC380/590TR, CR780T/440Y-TR, etc.
④JSC270C. DC01, DC03, DC51D+Z, etc.
⑤HC600/980QP, S700MC, etc.
⑥HC220P2, HC260LA, JSC 440Y, B280VK, SPFC780, etc.
⑦DC51D+AS, DC53D+MA, 409L, 439, etc.
⑧40Gr, GCr15, 60Si2MnA, 50GrVA, etc.
⑨B380CL, SPFH540, etc.
Commonly used brands of trucks
①SPA-C, HC400/780DP, S350GD+Z, etc.
②QStE500TM, 510L, 700L, SAPH440, SPFH590, etc.