DID YOU KNOW? DTIC has over 3.5 million final reports on DoD funded research, development, test, and evaluation activities available to our registered users. Click HERE
to register or log in.
TRANSITION PHASE IN MG-14LI-1A1-1ZN ALLOY
FRANKFORD ARSENAL PHILADELPHIA PA PITMAN-DUNN RESEARCH LABS
Pagination or Media Count:
Certain Mg-Li base alloys have good strength-toweight ratios in the cast and heat treated condition. The major drawback for using these alloys is their lack of stability during aging at slightly elevated temperatures. Mechanical property studies and X-ray diffraction work were performed on three Mg-Li base cast alloys Mg-14Li-1Al-1Zn, Mg-13.6Li-4Al-1Zn, an Mg-14.1Li-1Al. Tensile properties of the alloys in the following conditions were determined cast cast and aged and cast, solution treated, and aged. Debye-Scherrer X-ray diffraction patterns were taken of all alloys in the various conditions. A transition type phase was detected in the two quaternary alloys. X-ray diffraction lines from this phase corresponded to an Fd.. Fd3 or Fd3m space group with a lattice parameter of approximately 6.7 Angstroms. Prolonged aging at 200 F resulted in the transformation of this phase to the stable AlLi compound. This phase was not detected in the ternary alloy, but prolonged aging produced the AlLi phase. Author
APPROVED FOR PUBLIC RELEASE