Failure Analysis for a Detent Mechanism of Missile Launcher

Failure occurred as locking of the detent mechanism during the locking force test for a launcher. The launcher was inspected and the failure reason was the stopping of detent mechanism fractured.The fault tree was listed for the possible reasons of the stopping fracture.Possible reasons in the fault tree were analyzed and inspected,it was certain that the reason of the stopping fracture was the smaller rounding increases stress concentration. The relation between rounding and stress on the back stopping was analyzed with ANSYS software,which showed that rounding improved obviously stress concentration.So the stress concentration position of the stopping was improved on design to solve the problem of the stopping fracture.