Are Cars Still Made Out of Steel?

Yes. Most cars are still largely made of steel—especially the structural “safety cage,” frames, and crash components—but modern vehicles are now multi‑material, combining high‑strength steels with aluminum, plastics, and composites to balance strength, weight, cost, efficiency, and repairability. The mix varies by model and segment, with electric vehicles and luxury models often using more aluminum or composites, while mass‑market cars and many SUVs rely heavily on advanced steels.

What “made out of steel” means today

Automakers rarely build cars from a single material. The core of a vehicle—called the body‑in‑white (BIW)—and, in body‑on‑frame trucks, the frame, remain predominantly steel. Crucially, today’s steel isn’t just the mild sheet metal of decades past. It includes high‑strength steel (HSS), advanced high‑strength steel (AHSS), ultra‑high‑strength/press‑hardened steel (UHSS/PHS), and tailored, laser‑welded blanks. These grades let manufacturers design lighter structures that still meet ever‑stricter crash and rollover standards, while galvanized coatings and better paint systems improve corrosion resistance.

Where steel is used in modern vehicles

Steel remains the go‑to for safety‑critical, load‑bearing, and cost‑sensitive parts. The following components are commonly steel in most contemporary vehicles:

• Body‑in‑white structures: A‑/B‑/C‑pillars, roof rails, rockers, cross‑members, and floor pans, increasingly in AHSS and PHS for crash energy management.
• Frames and subframes: Especially in body‑on‑frame pickups and SUVs; even aluminum‑bodied models often ride on high‑strength steel frames.
• Crash structures: Front/rear rails, reinforcements, door intrusion beams, and battery protection cages in EVs.
• Suspension and chassis parts: Control arms, springs (sometimes), and mounting points, where durability and fatigue strength are critical.
• Powertrain and driveline elements: Many gears, shafts, and housings remain steel for wear and heat resistance (EVs use fewer but still need robust steel parts).
• Seats and restraint system structures: Frames and anchor points require high strength and stiffness.
• Wheels and base hardware: Steel wheels on entry‑level trims; numerous brackets and fasteners across trims.

These applications leverage steel’s unique combination of strength, formability, crash behavior, cost efficiency, and mature supply chains—qualities that remain difficult to match at scale with alternative materials.

Where other materials are taking over

To reduce weight, improve efficiency and range, or achieve distinctive styling, automakers increasingly deploy other materials alongside steel. Here’s where they show up and why:

• Aluminum: Doors, hoods, trunk/tailgates, fenders (“closures”) for lightweighting; structural castings and extrusions in EV platforms; notable examples include aluminum‑bodied pickups (e.g., Ford F‑150) and large aluminum castings in vehicles like Tesla Model Y/3.
• Magnesium: Steering wheel frames, seat components, and select housings where ultra‑low weight is desirable.
• Plastics and polymer composites: Bumper covers, interior panels, dashboards, and under‑body aero shields; glass‑fiber‑reinforced plastics for selective structural panels in some models.
• Carbon fiber: Used sparingly in high‑end sports cars and limited‑run models for roofs, hoods, or tubs; mass adoption remains limited due to cost and cycle times.
• Stainless steel: Rare, but prominent in the Tesla Cybertruck’s cold‑rolled stainless “exoskeleton,” trading weight and manufacturability for surface hardness and a unique aesthetic.

These materials are chosen to complement steel, not replace it wholesale. In practice, the optimal solution is a tailored, multi‑material mix guided by performance targets, cost, and manufacturing strategy.

Why not all steel? The trade‑offs

Material selection is a balancing act among many constraints. Automakers weigh the following factors before locking in a design:

• Weight and efficiency: Lighter materials boost fuel economy and EV range; advanced steels trim weight without sacrificing safety.
• Cost: Steel is generally cheaper and widely available; aluminum and carbon fiber can be costlier in material and processing.
• Manufacturability: Steels stamp quickly in high volumes; aluminum needs different forming, joining, and repair techniques; large castings require specialized tooling.
• Repairability and insurance: Steel is familiar to body shops; aluminum and composites can raise repair costs and cycle times.
• Corrosion and durability: Modern galvanized steels resist rust; aluminum resists corrosion but brings galvanic concerns in mixed joints.
• Safety and crash performance: Advanced steels deliver predictable energy absorption and intrusion resistance; mixed‑material joints demand careful engineering.
• Thermal and fire considerations (EVs): Battery enclosures balance heat management, puncture resistance, and weight, using steel, aluminum, or hybrid designs.
• Sustainability and recycling: Both steel and aluminum have high end‑of‑life recycling rates; the carbon footprint depends on how they’re produced (e.g., electric arc furnace steel, low‑carbon aluminum smelting).

No single material wins on every metric. The best designs exploit each material where it performs best, while minimizing trade‑offs.

Industry snapshot and trends (2024–2025)

Most mass‑market cars worldwide still include a majority of steel by mass, often on the order of roughly half the vehicle weight, with AHSS and PHS shares continuing to grow. EVs and premium segments are driving faster adoption of aluminum—especially for closures, battery enclosures, and large structural castings (“gigacastings”)—to offset battery mass. Meanwhile, steel remains central for occupant safety structures, cost control, and global manufacturability. Atypical approaches, such as the stainless‑steel Cybertruck exoskeleton, are outliers rather than the new norm. Automakers are also investing in low‑carbon steel (EAF, DRI/H₂) and greener aluminum to cut lifecycle emissions without abandoning proven materials.

Typical material mix ranges today

While every model is different, the following ranges describe many mainstream vehicles, noting that EVs and luxury models may skew toward more aluminum:

• Steel (including AHSS/UHSS): approximately 45–65% of vehicle mass.
• Aluminum: approximately 10–20% (higher in some EVs and premium cars).
• Polymers and composites: approximately 8–15%.
• Other materials (magnesium, copper, glass, rubber, etc.): the remainder.

These ranges reflect industry averages and will vary with vehicle size, segment, performance goals, and manufacturing strategy.

Examples across the market

Recent production vehicles illustrate how the material mix differs by mission and brand:

• Compact sedans/hatchbacks (e.g., Toyota Corolla): Steel‑intensive BIW with growing AHSS content for safety and cost efficiency.
• Full‑size pickups (e.g., Ford F‑150): Aluminum body panels over a high‑strength steel frame; rivals often use steel bodies and frames.
• Mainstream EVs (e.g., Tesla Model Y/3, various Chinese brands): Mixed‑material bodies with large aluminum castings plus extensive AHSS for crash structures.
• Aluminum‑intensive EVs (e.g., Jaguar I‑Pace): Heavier use of aluminum in body structures to compensate for battery mass.
• Special cases (e.g., Tesla Cybertruck): Stainless‑steel exoskeleton for exterior panels; unusual in mass production due to forming and repair complexity.

These illustrate the design freedom—and trade‑offs—enabled by modern material strategies.

Recycling and sustainability outlook

Steel and aluminum both have robust recycling streams, with high end‑of‑life recovery rates. The industry is moving toward lower‑carbon production—electric arc furnace (EAF) steel using recycled scrap, direct‑reduced iron (DRI) with green hydrogen, and aluminum smelting powered by renewable or hydroelectric energy. As mixed‑material bonding (adhesives, rivets, laser welding) becomes more common, designers are also rethinking joints to improve disassembly and closed‑loop recycling. For EVs, durable steel or aluminum battery enclosures are being engineered with future reuse and recycling in mind.

Summary

Cars are still very much made out of steel—especially the parts that protect occupants—but they are no longer made only of steel. The modern automobile is a multi‑material machine: advanced steels for strength and crash safety, aluminum for weight savings and range, polymers for design and cost, and specialty materials where they make sense. Expect steel to remain a backbone material, even as aluminum castings and other alternatives grow where they deliver clear advantages.

When did cars stop being made of steel?

Cars did not completely stop being made of steel; rather, the use of steel for the majority of car bodies decreased significantly as the automotive industry began incorporating other materials like aluminum, high-strength steel alloys, and plastics starting in the late 20th century, with the trend continuing through today. While all-steel cars were common for decades after 1914, a shift toward lighter materials for improved fuel efficiency and durability led to the integration of these other components into modern vehicle construction. 
Here’s a breakdown of the evolution:

• Early 20th Century: Steel became the dominant material for car bodies after Dodge introduced the first all-steel automobile in 1914. 
• Post-WWII Boom: Steel’s strength and malleability made it ideal for mass production, though its weight was a growing concern for fuel efficiency. 
• Late 20th Century: The automotive industry began to adopt other materials: 
  • High-Strength Steel Alloys: These offered similar or greater durability than traditional steel but with significantly less weight. 
  • Aluminum: Experimentation with aluminum for everyday cars began in the late 1970s, and its use has grown considerably since. 
  • Plastics: Were used in car interiors starting in the 1920s and became more prevalent in exteriors and other components over time. 
• Today: Modern cars are constructed using a blend of materials, including steel for chassis and some body panels, and other metals and plastics for various parts. Carbon fiber is also used, especially for high-performance vehicles. 

Are any cars made of steel anymore?

Yes, cars are still made of steel, with steel making up about 54% of the average vehicle’s mass, though modern vehicles also incorporate other materials like aluminum, plastic, and carbon fiber for various parts. Modern cars utilize advanced steel, such as Ultra-High-Strength Steel (AHSS), in body structures to achieve lighter weight, enhanced safety, and better fuel efficiency. 
Steel in Modern Cars

• Structural component: Steel is a primary material for vehicle bodies and chassis due to its strength, durability, and cost-effectiveness compared to other metals. 
• Safety: The use of advanced steel grades helps create a vehicle’s unibody structure, which is crucial for absorbing crash energy and providing rigidity. 
• Versatility: Steel can be easily manufactured and formed into complex shapes, but its properties can vary depending on the specific grade, like mild steel and high-strength steel. 

Other Materials

• Aluminum: Opens in new tabUsed for parts like hoods and rear deck lids to reduce weight, though it is more difficult to repair and has limited memory properties. 
• Plastic: Opens in new tabA common material for various parts, including front and rear fascias, bumpers, and interior components, often chosen for its low cost and contribution to fuel efficiency. 
• Carbon Fiber: Opens in new tabAn exceptionally strong and lightweight composite material but is generally too expensive for mass-market cars, typically reserved for high-end vehicles and racing. 

Why the Mix of Materials?
Car manufacturers use a mix of materials to balance cost, weight, safety, fuel efficiency, and manufacturing ease for different parts of the vehicle.

Why don’t we make cars out of stainless steel?

Cars aren’t made of stainless steel due to higher costs, difficulty in manufacturing, weight concerns, and safety implications. Stainless steel is significantly more expensive, harder to stamp and form into body shapes, and is also heavier than the mild steel typically used. Furthermore, its rigidity prevents the necessary crumple zones for effective crash energy absorption, creating a safety risk for occupants. 
Cost

• Higher Material Cost: Opens in new tabStainless steel is more expensive than conventional steel, sometimes costing twice as much, which would significantly increase the final price of the car. 
• Higher Production Costs: Opens in new tabThe complex machining and specialized welding techniques required for stainless steel also add to the overall production costs. 

Manufacturing Challenges

• Formability: Stainless steel is harder and less ductile than traditional car steel, making it more difficult and time-consuming to stamp into complex body shapes. 
• Damaged Tooling: Its hardness can damage the production dies used to form car parts, further increasing manufacturing expenses. 
• Repair Difficulty: Dents and other damage on stainless steel panels are more noticeable, and traditional repair methods like filler and paint are not as effective, making repairs more difficult. 

Safety Concerns 

• Crashworthiness: Stainless steel’s rigid nature means it does not crumple or absorb crash energy as effectively as the steel in most cars.
• Increased Impact Force: This lack of crumple zones would transfer more impact force to the occupants, posing a greater risk of serious injury during a collision.

Weight and Weight Management

• Increased Weight: Stainless steel is heavier than the mild steel currently used in cars. 
• Impact on Performance: The added weight would necessitate more robust suspension systems and potentially impact a vehicle’s overall performance and fuel efficiency, which car manufacturers aim to minimize. 

When did cars go from metal to plastic?

Plastics first saw use in car interiors in the 1920s. First exterior use was in the late ’40s when metal parts coated with simulated wood-grain vinyl replaced real wood veneers on outside sheet metal for the classic “woody” look. By the 1960s, vinyl took over vehicle interiors.