Dear Prof. Di Chen:
 I think you can check Ni shear modulus in the following website, which is
 80MPa.

http://www.efunda.com/materials/common_matl/Common_Matl.cfm?MatlPhase=Solid&
MatlProp=Mechanical#Mechanical

 Best regards

 Yanjun(David) Tang

 Graduate student
 Institute for Micromanufacturing
 Louisiana Tech University

 1401 Tech Farm Rd. Apt. #238, Ruston, LA 71270, USA
 Email: yta001@coes.latech.edu
           tang_yanjun@yahoo.com
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 Tel: 1-318-255-5133