In a speech at an annual steel conference in New York, he said that further consolidation in the industry would be required to allow steelmakers flexibility to get to grips with the cyclical nature of the market.

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In the 1990s, when the "old-technology" steel industry in the U.S. was failing, Bain Capital helped build a new steel company, Steel Dynamics, which has grown into one of the largest steel producers in America today, holding its own against Chinese producers.

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Lightweight materials aluminum, magnesium, carbon fiber and new kinds of steel are going to be the key to achieving higher gas mileage in the future, industry executives say.

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