Results:

 

 

Out of the three sample of String G that I experimentally fractured, two appeared to fail by slip as indicated by the striations seen in the cross-sectional images. I estimate that this slipped plane is where the fracture initiated by crack formation. Before reaching the middle plane of the cross-section, the fracture appears to have spherical dimples, indicative of brittle fracture. The third String G that I observed had a cup-and-cone fracture surface. Therefore, brittle fracture is the dominant mode of fracture in the String G.

All of the B and E strings thrat I studied failed by cup-and-cone fracture. This fracture mode is characteristic of ductile fracture. Considerable plastic deformation by necking was indicated by the decrease in cross sectional area closer to the fractured cross-section.

 

Acknowledgments

 

I would like to thank Professor Wayne Knox from the Department of Optics for giving me the opportunity to work with this topic, and for providing me his guitar and string samples for experimentation.

I am grateful to Brian McIntyre and Rohit Puranik, as well as my labmates Ivy Xue and Maria Abreu Sepulveda for their constant guidance and advice.

 

References

1.Olver A, Wilson D, Crofton Shaun: Investigation of service failures of steel music wire. In: Vol 14. Engineering Failure Analysis, 2007, pp. 1224-1232.

2. "http://daddario.com/DADProductDetail.Page?ActiveID=3769&productid=74&productname=EJ16_Phosphor_ Bronze__Light__12_53."www.daddario.com. N.p.. Web. 1 May 2013.