Microstructure characteristics and acoustic properties of laser repaired Chinese bronze bells 2300 years ago

Six broken Chinese bronze bells, unearthed from Jiu-Lian-Dun tomb of the warring states period 2300 years ago, are repaired successfully in shapes and acoustic properties by laser welding. The tone pitches of repaired bells are harmonious and well coherent with those of nearby bells. The investigation shows the weld metal has a good consistency with base metals in both microstructure and chemical components, which is the main mechanism to recover the bell's acoustic property. Besides, both the microstructure of weld and base metal are dendrites consisting of pro-eutectoid α-Cu and the eutectoid (α-Cu + δ-Cu6Sn5) between the dendrite arms.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights▶ Six Chinese bronze bells, unearthed from Jiu-Lian-Dun tomb of the warring states period 2300 years ago, are repaired successfully by laser welding. ▶ The shape and acoustic properties of repaired bells are well recovered. ▶ The weld metal has a good consistency with base metals in both microstructure and chemical components, which is the main recovering mechanism.