Coarse Grain Annealing

A specific annealing treatment in the upper temperature range to purposefully increase austenite grain size. This improves machinability in certain steel grades, albeit usually at the expense of mechanical toughness.

You get coarse grain formation if you anneal the steel long enough and hot enough, so the grains can really grow. That makes the material softer and easier to machine, but it doesn't make it tougher – on the contrary, the strength suffers.

MetallurgieSchweißtechnik