Acoustic Emission (AE) Monitoring of Open Die and Closed Die Forging Processes of Al Alloy

Abstract

Acoustic emission (AE) generated during open die and closed die forging processes of Al alloy has been studied. AE generated during both types of the forging processes could be differentiated into three stages, namely, yielding of the workpiece material upon start of forging, intermediate deformation and filling of the die. The effect of lubrication on the AE generated during open die forging was also studied. This showed that AE increases with decreasing lubrication of the workpiece thus enabling AE to detect lubrication inadequacy/breakdown during the forging process.

Keywords:

• Acoustic emission (AE)
• Al Alloy
• Closed die forging
• Die filling
• Dislocation avalanche
• Forming
• Friction
• Lubrication
• Monitoring
• Nondestructive technique
• Open die forging
• Peak amplitude distribution
• Piezoelectric
• Sliding
• Yielding

ACKNOWLEDGMENT

Authors thank Mr. P. Kalyanasundaram, Associate Director, Inspection Technology Group, Indira Gandhi Center for Atomic Research, Kalpakkam for his cooperation.