Which kinds of steel are commonly found in cars?

• Stainless steel
• Advanced high-strength steel
• High-carbon steel
• Low-carbon steel
• Galvanized steel

steel used in cars has played an undeniable role in the automotive world. Its ability to be shaped and fabricated into various forms using different manufacturing methods makes it a reliable, economical, and sturdy choice. Automotive steel types comparison, including stainless, high-strength, high-carbon, low-carbon, and galvanized varieties.

These materials are essential in building countless vehicle and engine parts, such as bushings, bearings, exhaust systems, radiators, frames, chassis, and wheels. Without a doubt, steel has established itself as one of the most trusted and versatile materials in the history of manufacturing.

To understand why this easily accessible material remains so vital, let’s dive deeper into the major steel types found in cars and their specific roles. Each steel grade enables automakers to develop new, innovative vehicle designs and features. Let’s explore each type in detail.

Stainless Steel

A steel product can only be labeled “stainless” if it contains at least 10.5% chromium, about 1% carbon, and other alloying elements. One of its most notable characteristics is its excellent corrosion resistance. Its shiny, lightweight form has become a symbol of durability and practicality across multiple industries, including automotive manufacturing.

It’s no surprise that stainless steel is widely chosen for assembling different car parts. In fact, many vehicles contain between 15 and 20 kilograms of stainless steel, mostly in exhaust systems.

Engines that burn fuel require components that can endure high temperatures without deforming or melting. Stainless steel, with its melting point exceeding 1,500°C, is ideal for these conditions. Considering that a running car engine can reach 90 to 104°C, stainless steel helps protect other parts of the vehicle and contributes to overall safety during operation.

Representative grade

Austenitic type: SUS304 (corresponding to AISI 304), SUS316 (corresponding to AISI 316)

Ferritic type: SUS409, SUS430

Martensitic type: SUS410, SUS420

Advanced High-Strength Steel

Innovations in steel production have resulted in advanced high-strength steel (AHSS). Unlike basic low-carbon or mild steels, AHSS features a complex composition and undergoes precise heating processes, which enhance its toughness, ductility, and fatigue resistance.

Thanks to these properties, AHSS is an excellent material for vehicle bodies, frames, doors, bumpers, and undercarriages, as it allows for lighter designs without compromising strength. Manufacturers are continually developing ways to integrate AHSS into cars to meet performance, safety, and cost requirements.

AHSS includes various categories such as martensitic (MS), ferritic-bainitic (FB), transformation-induced plasticity (TRIP), and twinning-induced plasticity (TWIP). TRIP and dual-phase (DP) steels are great for crash zones due to their energy absorption capabilities. Meanwhile, MS steels help improve safety and overall performance.

Representative grade

Dual Phase (DP)：CGCH980DP, PGT980D-M, CGCH590DP, CGCH780DP

TRIP：CGCH590TR, CGCH780TR

TWIP：CGCH980TW

Complex Phase：CGCH1180CP, PGT1180P

High-Carbon Steel

High-carbon steel refers to steel with a higher carbon content that has been processed through quenching — a rapid cooling method. In contrast to conventional heat treatment where carbon diffuses into heated iron, quenching traps the carbon, changing the steel’s structure.

This steel type is less ductile and more brittle compared to regular steel, but its excellent wear resistance makes up for it. That’s why it’s often used to produce cutting tools and fasteners.

Automakers utilize high-carbon steel in frames, chassis, bushings, door panels, support beams, and mufflers. When combined with other steel grades, it helps create vehicles that meet strict safety and crash standards while also enabling diverse design possibilities.

Representative grade

Commonly used international standards (JIS, SAE standards)

SAE 1050 / S50C (carbon content approximately 0.50%)

SAE 1060 / S60C (carbon content approximately 0.60%)

SAE 1070 / S70C (carbon content approximately 0.70%)

SAE 1080 / S80C (carbon content approximately 0.80%)

Low-Carbon Steel

Low-carbon steel, also called mild steel, has lower tensile strength and poorer yield-point runout compared to high-carbon steel. Despite these limitations, its low production cost and suitability for small parts make it a popular choice.

This type of steel is commonly found throughout a vehicle, both inside and out. Examples include clutch housings, suspension elements, control arms, and brackets. It is also used for decorative and fastening parts such as rims, covers, screws, washers, bolts, nuts, and other fasteners — all crucial for structural integrity.

Representative grade

CQ (Commercial Quality)：PGT270C-S, CSP1-S

LQ (Lockforming Quality)：PGT270L-S/-E, PCF270L-S/-E

DQ (Drawing Quality)：PGT270D-S/-E, PCF270D-S/-E

DDQ (Deep Drawing Quality)：PGT270DN-S/-E, PCF270DN-S/-E

EDDQ (Extra Deep Drawing Quality)：PGT270E-S/-E, PCF270E-S/-E

Galvanized Steel

Galvanized steel is a more affordable alternative to stainless steel and performs better than aluminum in many cases. Nowadays, it is a standard material in most vehicles, with nearly 80% of a typical car, truck, or motorcycle made from galvanized steel. A thin layer of zinc coating protects it, increasing durability and reducing the need for frequent maintenance or repairs.

The advantages of galvanized steel include its low cost, extended lifespan, self-healing ability, and widespread availability. It offers a cost-effective solution for parts that require solid protection without the expense of premium steel types.

Representative grade

Dual Phase：CGCH980DP, CGCH780DP

Baked Hardening：CGCH350BH(-E), CGCH550DD

Rephosphorized grade：CHSP50C, CHSP60C

IF grade：CGCH35, CGCH45, CGCH52S(-E)

Key Takeaway

Steel in its various forms is found throughout nearly every part of a vehicle. As we’ve covered, certain steels provide excellent strength and crash protection, like advanced high-strength and high-carbon steels. Others, such as stainless steel, galvanized steel, and low-carbon steel, offer a practical balance between strength and cost-effectiveness.

With the continuous progress of the automotive and steel manufacturing industries, manufacturers are constantly developing specialized steel components. If you also want to know more about steel information, you can contact us and we will explain it to you in detail.