⚙️ Every electric car hides an iron heart: a tightly packed stack of steel sheets, each thinner than a business card, spinning thousands of times a minute. Get that stack even slightly wrong and the motor bleeds energy as heat. The tooling that stamps and bonds those sheets is an overlooked chokepoint of the EV era, and one of the firms that shapes it employs fewer than a thousand people. Now it is betting on two metals that defeated engineers for decades.

The part no one sees inside an electric motor

An EV motor core is a stack of laminations: hundreds of stamped rings of electrical steel, insulated from one another and pressed together. The steel itself comes from giants like Nippon Steel, JFE and POSCO. But turning a coil of that steel into a finished core, punching each layer to micron tolerances and locking the layers together without shorting them, is a craft of its own. That craft lives in the stamping die.

Kuroda Precision Industries, based in Kawasaki just outside Tokyo, is one of the world's leading makers of those dies for EV drive motors. According to the Nikkei, it holds roughly 30 percent of the global market for EV-drive motor-core dies, sitting in the top group of suppliers. It is not a household name. The company runs on about 988 staff and booked ¥18.5 billion (around $114 million) in revenue for the year ended March 2024. It started in 1925 making measuring gauges and marked its centenary in 2025.

For most of that century, gauges and ball screws were the business. Motor-core dies changed that. Until about two years ago, president Hiroshi Kuroda has told the trade press, ball screws were the mainstay; now motor-core work in the die business is the company's largest line. More than 30 mass-production projects are running worldwide, most of them in North America, and roughly 85 percent of the die division's sales go overseas.

Why stamping steel is harder than it sounds

How efficient a motor is comes down to how little energy leaks away as heat inside the core, a loss engineers call iron loss. One way to cut it is to make each lamination thinner and stack more of them. But thinner sheets are fussier to punch, and the traditional trick for holding the stack together, crimping little dimples through it, creates tiny electrical bridges that leak energy.

Kuroda's answer was to glue the layers inside the die itself. Its Glue FASTEC process lays adhesive onto each sheet and bonds the stack as it is stamped, keeping the layers electrically isolated. The company says the method lifted productivity by more than 10 percent, cut iron loss by 10 to 20 percent, and raised motor torque by 17 percent against the conventional approach. The recipe is deliberately kept as a black box, which is much of why rivals struggle to copy it.

That moat matters, because the competition is fierce and fast. The broader motor-core die market is led by fellow Japanese firm Mitsui High-tec, with Italy's EuroGroup Laminations and a rising wave of Chinese makers close behind. Chinese suppliers such as Ningbo Zhenyu are winning EV die orders fast, competing hard on development speed as much as on price.

The forty-year wall: metals that fight back

The next frontier is not the die but the metal it stamps, and here Kuroda is walking straight into problems that have blocked the whole industry for decades.

The first is amorphous alloy, an iron-silicon-boron ribbon cooled so fast from the melt that it never forms a crystal structure. Its iron loss can fall to a tenth of ordinary electrical steel, which is huge for fast-spinning motors. Engineers have known this since the 1980s. The catch is the ribbon itself: thin, hard and stubborn, it was, for roughly forty years, nearly impossible to punch and stack in volume without destroying the tooling.

The second is permendur, an alloy of iron and cobalt in almost equal parts. It carries the highest saturation flux density of any practical soft-magnetic material, which lets a motor be smaller, lighter and more powerful. That makes it a candidate for high-speed motors and the electric aircraft known as eVTOLs. But permendur turns brittle if it cools too slowly through a critical temperature, and it is about half cobalt by weight.

Vision2030 and the bet on difficult metal

In mid-2026 Kuroda launched a five-year plan called Vision2030, using its centenary as the pivot. The near-term move is concrete: according to the trade paper Japan Metal Daily, mass production of EV motor cores begins in the second half of the current fiscal year. The company has already built out capacity at its Nagano mother factory, where an eighth plant, completed in late 2023, houses a 300-ton high-speed press. The longer bet is on the difficult metals. By throwing its die and lamination know-how at amorphous and permendur, the company is angling for high-speed motors, aircraft electrification and other future uses rather than the mature EV core alone.

It is a fitting move for a firm whose die chief, Katsunori Ishii, likes to say its engineers have seen more motor-core drawings than anyone in the world. The strategy is not to build the motors, or even make the steel, but to own the hardest step in between.

Cobalt, geopolitics, and whose motor you are driving

Permendur's cobalt content is where the story stops being about metallurgy and starts being about maps. The Democratic Republic of Congo mined about 76 percent of the world's cobalt in 2024, according to the Cobalt Institute. In February 2025 the DRC halted cobalt exports to prop up prices; the benchmark LME three-month price jumped from around $21,550 a tonne to $36,170 within weeks, and the ban was extended repeatedly through the year. A material that could help put electric aircraft in the sky also ties them to one of the most concentrated supply chains on Earth.

That is the backdrop to a contest most drivers never think about. The iron heart of the motor in your next EV was shaped by a die, and that die was most likely made in Japan, Italy or China. Japan's edge rests on hard-won process secrets; China's on speed and scale; Europe's on integrated, large-diameter production. The motor-core die market is still small enough that the top five makers account for only about half of global revenue, which means the balance can still shift.

So here is a question worth asking next time you settle into an electric car: whose motor core is spinning under the floor, and where was the die that stamped it actually made?

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