Abstract:

In order to control and optimize the child protection performance in the early stage of passenger vehicle design， taking a case as an example that the spot welds of ISOFIX fixing device in a passenger vehicle are pulled off from vehicle body， leading to a failure. Based on the spot weld heat affected zone failure criteria and the sheet metal fracture failure criteria， finite element analysis（FEA） is used to conduct virtual evaluation and structure improvement， and the FEA results well agrees with test ones. Finally， it passes the child seat pull bench test， showing that the strength analysis of body structure based on child seat pull safety performance has good reliability and applicability.

Key words: ISOFIX, child seat pull failure, spot weld heat affected zone