Rocker arms and valve springs require different groups of tough friends. Still image from video.
The automobile has grown exponentially in complexity since 1938, but one thing still rings true: Steel is the basic building block of its construction. As this Jam Handy production demonstrates, steel’s Tough Friends can help it cope with the wide variety of conditions, ensuring both safety and durability.
Even in 1938, the average automobile consisted of more than 4,500 parts, many of which were built of steel or other metals. Bodies and roof sections were stamped from carbon steel for strength and durability, while the hardness of chromium steel was preferred for gears. Brake drums were made from cast iron, favored for its resistance to high temperature and quick cooling, while steel mixed with both chromium and silicon was used to manufacture intake and exhaust valves, ensuring both strength and heat resistance. Even in the prewar years, more than 80 different types of steel alloys had been developed for the automobile, each meeting specific criteria for hardness, elasticity, heat resistance and strength. No matter what the final alloy or product, each began life as iron ore, and later, as a steel ingot.
Modern car design and construction still rely on roughly the same materials, although the alloys have become far more sophisticated in the decades since Jam Handy produced this educational spot for Chevrolet. Body structures, now with integrated frames instead of separate box frames, are made from a variety of steel alloys, each with varying properties. Some are designed to fold with relative ease, creating “crumple zones” that help to dissipate crash energy and protect occupants; others are extremely strong, ensuring cabin integrity in the result of a rollover crash.
Non-steel materials are playing an ever-increasing role in modern automobile construction, with many body panels now made from plastic, aluminum or carbon fiber. Carbon composites have even found their way into braking systems, allowing the construction of brake rotors that are extremely heat resistant yet very light (and very, very expensive). Even the origin of steel materials used in modern automobiles is no longer so black and white, as recycling plays an ever-increasing role in the production of the metals used in new car construction.
Still, the basic rule applies: In order to create steel-based alloys that meet the requirements of today’s automobiles, the metal needs to count on a pool of (increasingly diverse) tough friends.