关键词: 电磁热, 埋藏裂纹, 球形孔洞, 止裂

Abstract:

Electromagnetic heat effects can achieve crack arresting and strengthening of metal structures with half-embedding crack and embedding crack.In fact,hole defects often exist in castings and forgings.The effects of electromagnetic heat strengthening on hole defects were analyzed from theory and numerical simulation,and the current density and temperature distribution were derived while the current flowing around a sphere.The researches show that hole  defects can be treated as generalized embedding defects,and the application of electromagnetic heat strengthening and crack prevention is feasible.After current discharged,the current flows around the spherical cross-section in the direction perpendicular to the current.The temperature exceeds the melting point of the material immediately to form welded joints.Pressing stress reduces the stress concentration significantly, which inhibits the crack expanding when the hole defects are forced, therefore, this method can achieve the effect of crack arresting and strengthening.

Key words: electromagnetic heat, embedding crack, spherical hole, crack arrest