1.What effects does friction have on a forminglimit diagram? Explain. By the student. Friction can have a strong effect on formability. High friction will cause localized

strains, so that formability is decreased. Low friction allows the sheet to slide more easily

over the die surfaces and thus distribute the strains more evenly.

2.Why are lubricants generally used in sheetmetal forming? Explain, giving examples.

Lubricants are used for a number of reasons. Mainly, they reduce friction, and this improves

formability as discussed in the answer to Problem