Memoranda

On Tuesday, Jan 21, 1997, manufacturing process lab visited Hansen/Balk steel treating company in the city of Grand Rapids. Our host and guide was Steve. Hansen/Balk's business is applying different heat treatments to customers steel products and hardness testing of the finish products. There primary metal hardening operations are for all tool steel treating, stainless steel treating carbonizing, flame and hardening stress relieving. Hansen/Balk has been in business since 1955

During our tour, Steve show us different heating machinery. There were many new machines that used microprocessor technology to monitor and control the processes. The tempering machines keep temperatures to within 8 and the hardening machines to within 33 while reaching temperature of 1400 degrees. These machine were capable of removing the atmosphere from the heated chambers and replacing it with an inert gas. The gas used are hydrogen, argon and nitrogen. These gases gave different properties and hardness to the material. The ion nitride machine gives a hard ware resistance to the metal. It's process required the sample to be held at elevated temperature for fifteen hours. Steve said the choice of gas is usually chosen by the customers. Gas is used to minimize oxidation of the parts during the heat treatmenting process and has a quality looking finish. Heat treating without a shielding gas require sand blasting to achieve a quality look. Both methods are offered at Hansen/Balk.

Another process we viewed was flame hardning. An operator drug a tool that had two operations going at the same time across the surface of a metal part. On one side of the tool was a very hot flame. It was able to raise the surface temperature to austenitizing temperatures. Directly behind the flame was a spray tip that quickly cooled the surface metal with a plastic quenching solution. This was real neat to see. The result of flame hardning is to harden the surface of the metal while not changing the properties of the rest of the metal. A purpose for this type of heat treatment is to change the ware resistance of the surface of the metal while keeping the ductility and strength of the rest of the piece.