Microstructure Evolution in Ti-Al-Mo-Fe-Mn-Cr-Cu Alloys containing Rare-Earth Metals
Lanthanum-containing (α+β)-titanium alloys like Ti 6Al 4V 0. 9 La alloy show improved machinability due to the formation of shortbreaking chips. The microstructure of Ti 6Al 4V 0. 9 La exhibits an (α+β)-titanium matrix and metallic lanthanum particles located only on the grain boundaries. This particle morphology resulted in reduced ductility compared to the standard alloy Ti 6Al 4V. Therefore, new free-machining (α+ β)-alloys were developed,produced and investigated. Alloy development resulted in the two multi-component alloys Ti 6A1 2Fe 1Mo 0. 9La and Ti 6Al 2Fe 1Mo 0. 9La 0. 5Cu showing a more homogenous particle distribution on the grain boundaries and within the grains. The particles consisted of pure metallic lanthanum as well as of lanthanum-based intermetallic compounds. During crystallization of Ti 6A1 2Fe 1Mo 0. 9La and Ti 6Al 2Fe 1Mo 0. 9La 0. 5Cu a tendency to intercrystalline crack formation has been observed. To understand the underlying mechanisms and their dependence of the alloying elements model alloys,namely Ti 6Al 2X 0. 9La (X=Cr,Mn or Fe),containing different β-stabilizers have been studied in Scheil-Gulliver simulations and solidification experiments.
Titanium (Ti) lanthanum particles (La) machining microstructure alloy development ThermoCalc(R) simulations solidification interval
Judith Laukart Carsten Siemers Joachim Rosier
Technische Universit(a)t Braunschweig,Institute for Materials,Langer Kamp 8,38106 Braunschweig,Germany
国际会议
The 12th World Conference Titanium(第十二届世界钛会 Ti-2011)
北京
英文
459-463
2011-06-19（万方平台首次上网日期，不代表论文的发表时间）