The first industrially induction hardened part was a crankshaft (the early 1930s). As time went on, crankshaft designs became more complicated and heat-treatment specifications became more challenging. At the same time, crankshaft coil design has not advanced significantly since the 1960s. In many cases, this has resulted in limited ability to meet newer part specifications and short induction-coil lifetimes.
Check out the May 2017 issue of Industrial Heating, which includes features on Ford's $1.2 billion investment in three Michigan facilities, a roundup of heat-treat process-verification articles, and much more.