North American Automotive Metal Stampings: Supply Base and Application Map

North American light-vehicle production runs at roughly 15 to 16 million units a year across the United States, Canada, and Mexico. Each of those vehicles carries about 900 kilograms of steel and, on the fleet average, 200 kilograms of aluminum, and the largest share of both goes through a press. The body-in-white, closures, chassis stampings, seat frames, and brackets together account for 350 to 450 kilograms of stamped and roll-formed metal per vehicle, which puts the North American automotive stamping market in the range of six million tonnes of sheet a year before scrap.

The material mix has moved faster in this lens than in any other. In 2005 a typical body-in-white was mostly mild and HSLA steel. On a new program today, advanced high-strength steel and press-hardened boron steel are 60 to 70 percent of the structure by mass, and aluminum sheet has taken the hood on most trucks and premium vehicles, the doors and body side on a few, and the battery tray on most EVs. Two forces drove that: crash tests (IIHS small overlap and side, FMVSS 214 and 216a) that reward strength per millimeter of section, and fuel economy and EV range that reward mass out. The steel mills answered with third-generation AHSS and hot stamping; the aluminum mills answered with 6xxx body sheet capacity in New York, Alabama, and Kentucky.

The supply chain does not look like the polymers chain. OEMs stamp much of the body-in-white in-house. GM, Ford, Stellantis, Toyota, and Honda each run large stamping plants, and the Class A outer panels rarely leave them. The OEM also buys the steel: on most Detroit Three programs the OEM negotiates the coil price with the mill and resells it to the stamper, so the Tier 1 stamper is selling conversion, not material. Tier 1 is the independent structure supplier that takes what the OEM does not press, above all the hot-stamped pillars, rails, and rockers that need a furnace and a quench die the OEM press shops mostly do not have. Tier 2 is the progressive-die bracket and reinforcement stamper. Tier 3 is the mill, and the service centers slit, blank, and hold inventory for anyone below railcar scale.

Demand sits in the same belt as vehicle assembly: southern Ontario and Michigan, Ohio, Indiana, Kentucky, Tennessee, Alabama, Georgia, South Carolina, and the Mexican Bajio and Saltillo corridors. The mills are in Ohio, Indiana, Michigan, Kentucky, Arkansas, and Alabama for steel, and New York, Iowa, Tennessee, Alabama, and Kentucky for aluminum sheet. Section 232 tariffs and the USMCA steel and aluminum content rule have made that geography sticky.

The tier language is the same as in every other automotive report, but the tiers do different work here.

The OEM is a stamper. Every high-volume OEM in North America owns press shops: GM at Marion, Parma, Flint, Pontiac, and Fort Wayne; Ford at Dearborn, Chicago, Buffalo, Woodhaven, and Kentucky Truck; Stellantis at Sterling and Warren; Toyota inside its Georgetown and Princeton plants; Honda inside Marysville and East Liberty. Those shops press the body side outers, roof, doors, hoods, floor, and most of the large structural panels, and the body shop next door welds them. A Tier 1 stamper does not compete for those panels. It competes for what the OEM chose not to press, and that decision is made platform by platform, years before production.

The OEM also usually owns the steel. Under a resale steel program the OEM negotiates annual coil pricing with the mills for the grades on its material specifications, and the stamper buys that coil at the OEM price and is paid for conversion. The stamper carries little steel price risk and has little steel margin. Aluminum sheet often works the same way, and on the aluminum-intensive programs the OEM also runs the closed-loop scrap contract with the mill. A supplier at Tier 1 or Tier 2 is therefore selling press capacity, die engineering, weld and assembly, and quality, not metal.

Tier 1 is the independent structure supplier: Magna Cosma, Gestamp, Martinrea, Autokiniton, Benteler, voestalpine, Metalsa, Kirchhoff, Mubea, Flex-N-Gate. Their distinguishing assets are hot-stamping lines (a furnace, a transfer press, and a water-cooled die that quenches boron steel to 1500 MPa in the tool), large transfer presses above 2,000 tonnes, laser blanking and tailor-welded or tailor-rolled blank capability, and weld and assembly cells that deliver a complete front-end structure, subframe, or battery tray rather than a part. Most of the hot-stamping capacity in North America sits with about six of these companies, and that concentration is the single most important structural fact in the lens.

Tier 2 is the progressive-die stamper and the die maker. Presses from 200 to 1,000 tonnes, progressive and transfer dies built in-house or in the Windsor and Detroit tool shops, brackets and reinforcements shipped to Tier 1 weld cells and to the seat, exhaust, and interior Tier 1s. Many Tier 2s also sell direct to OEM plants for small parts. Tier 2 is where a hundred brackets per vehicle get made, and where a new entrant lands.

Tier 3 is the mill. Cleveland-Cliffs and U.S. Steel supply most exposed and coated automotive steel; Nucor and Steel Dynamics supply unexposed grades from electric arc furnaces and are working up the exposed-grade approvals; SSAB supplies the martensitic strip that roll-formed beams are made of. Novelis, Arconic, and Constellium roll the 5xxx and 6xxx body sheet, Kaiser and Constellium extrude, and Alcoa supplies primary metal. Service centers (Ryerson, Olympic Steel, Reliance, Kloeckner) slit, blank, and cut to length, and carry the inventory and credit for Tier 2s that cannot take a coil program direct.

Three things a supplier from another material world should know. First, the die is the capital: the OEM pays for and owns production tooling, so a stamper that cannot fund and engineer a die program to buy-off on the OEM timeline is not in the game. Second, PPAP on a stamping includes the material certification chain back to the heat, and USMCA steel and aluminum content rules have made that chain a customs document as well as a quality one. Third, hot stamping and Class A are separate businesses from bracket stamping, with different presses, different people, and different customers, and almost nobody does all three well.

The same eighteen OEM entities that buy polymers buy stampings, and the full roster with plant footprints is in the gated section of this report. What differs is how much each one presses itself and what it leaves to the supply base.

The Detroit Three own the largest press shops in the market and stamp their own outers, roofs, floors, and most large body panels. They buy hot-stamped structures, subframes, frames, cross-car beams, bumper beams, and seat and bracket stampings from Tier 1 and Tier 2, and they run resale steel programs that set the coil price for their suppliers. Ford is the aluminum buyer: the F-Series body has been aluminum since 2015, and the Expedition, Navigator, and Super Duty followed, which made Ford the anchor customer for Novelis, Arconic, and Constellium body sheet. GM and Stellantis mix materials by part, with aluminum hoods and liftgates on trucks and SUVs and steel elsewhere.

Toyota and Honda stamp heavily in-house and keep the supply base close: affiliated and long-standing suppliers, less churn between programs, and a preference for steel structures over aluminum where the mass math allows. Nissan, Hyundai, and Kia stamp their own outers and buy structures. The German transplants in South Carolina, Alabama, and Tennessee outsource more of the body structure than the Detroit Three, which is why Gestamp, Benteler, and voestalpine built hot-stamping plants in Chattanooga, Duncan, McCalla, and Cartersville.

Tesla presses its own panels in Fremont and Austin and has replaced whole stamped rear and front structures with single large aluminum castings, which removed dozens of stampings and their welds from the Model Y. Rivian and Lucid buy most of their structures from Tier 1. Every EV program, whichever OEM, has added a battery tray and lid that did not exist on the combustion vehicle, and that is the largest new stamped and extruded part family of the decade.