新しい応力の定義を用いたインデンテーション法によるはんだのクリープ変形評価

抄録

Indentation tests are effective methods to evaluate mechanical properties of materials. One of problems of indentation tests, especially, indentation creep tests, is a definition of reference area used to obtain indentation stresses. Recently, the authors proposed a new definition for the reference area of indentation creep tests. The definition is based on the surface area normal to the maximum principal stress during the indentation creep tests. The new definition of the reference area was verified by a series of numerical indentation creep tests. In this paper, using an indentation creep testing machine, indentation creep tests are carried out using a solder alloy of Sn-3.0Ag-0.5Cu and the new definition of reference area is verified. The effect of crystal size on the steady state creep is also discussed by the indentation creep tests.