Asarkar_kolkata: A forging and a casting might be distinguished based on surface features. A cast component might have a casting parting line that could be absent on a forging. The surface finish of a casting may be rougher than a forging, if sand cast. Typically, metallography is a useful tool for distinguishing between forgings and castings, based on grain size and orientation. We don't know of NDT techniques that can distinguish between a forging and a casting. Hope this helps! David Hendrix The Hendrix Group Inc.