2099 Aluminum-Lithium with Key-Locked Inserts for Aerospace Applications

摘要

The purpose of this study was to determine the acceptability of nonpenetrating, key-locked inserts in 2099 aluminum-lithium. The tests conducted to make this assessment were: (1) microscopic examination for thread damage and delaminations after key installation, (2) pull-out load at 21℃ (70 °F) and -179℃ (-290 °F), and (3) mechanical cycling tests at room temperature and -179℃ (-290 °F). The test results indicated that for the three sizes evaluated, key-locked inserts in 2099-T6 and 2099-T8 were acceptable and although delaminations did occur on some T6 temper specimens, it was only as a failure mode at ultimate load and such behavior was judged to be acceptable.