Cook Induction Heating Co. Leaders in Induction Heating & Metal Joining Since 1945. Heat Treating: Localized Hardening, Localized Annealing, Induction Case Hardening, Heat Treating of Beryllium Copper, Localized Annealing of Beryllium Copper, Hydrogen Annealing Tempering. Brazing/Soldering: Silver, Copper, Nickel, & Precious Metals, Induction, Torch, & Furnace, Atmosphere Induction Brazing, Soldering with all solders.