No. There is a law that says you can't MELT cent and non-silver five cent pieces, but you can chop them up beat them with a hammer, roll them out, fold them over or even scrunch them up into little cubes and that is all perfectly legal. Just don't melt them. There are NO restrictions on the other denominations. You can melt them to your hearts content. There IS a law against destroying or defacing US paper money.
Some people have wondered if altering a US coin is illegal. As long as there is no intent to defraud someone, as in counterfeiting, it is not illegal. Taken from: http://www.lincolncentsonline.com/Carved Cents.html