What method is used to prevent cracks when dimpling magnesium or hard sheet metals?

The use of hot dimpling equipment is an effective method for preventing cracks when working with magnesium and hard sheet metals. When these materials are dimpled at elevated temperatures, they exhibit increased ductility, which allows them to deform more easily without fracturing. Heating the metal reduces the risk of introducing stress concentrations that can lead to cracks during the dimpling process. This technique helps maintain the integrity of the material while achieving the necessary shape and contour.

Other methods, while they may provide some benefits, do not address the core issue of reducing the brittleness of hard sheet metals as effectively as hot dimpling does. For instance, using a special lubricant can aid in the dimpling process but does not necessarily prevent cracking associated with stress in hard materials. Cold stretching techniques are intended for different applications and may not provide the necessary malleability required. Similarly, using a slower speed on the machine may help in controlling the process but does not fundamentally alter the properties of the metal being worked.