Bulk metallic glass-based alloys for additive manufacturing
An alloy may include at least one first element, the first element being selected from: nickel (Ni), zirconium (Zr), cerium (Ce), molybdenum (Mo), aluminum (Al), tantalum (Ta), cobalt (Co), yttrium (Y), chromium (Cr), copper (Cu), and manganese (Mn); no more than three second elements, the second elements being selected from: phosphorous (P), carbon (C), boron (B), and silicon (Si); and the balance iron (Fe). Typically, a majority of a crystal structure of the alloy may be amorphous. In some instances, between 1 volume percent (vol. %) and 50 vol. % of the crystal structure may be a crystalline metal phase. The crystalline metal phase includes at least one of: copper (Cu), aluminum (Al), vanadium (V), chromium (Cr), iron (Fe), cobalt (Co), nickel (Ni), and molybdenum (Mo).
1 . An iron-based bulk metallic glass alloy comprising:
at least two first elements, the first element consisting of: when present, between 1 at % to 3 at % or between 12 at % to 14 at % zirconium (Zr), when present, between 12 at % to 14 at % molybdenum (Mo), between 13 at % to 15 at % aluminum (Al), when present, between 1 at % to 10 at % yttrium (Y), when present, between 1 volumetric percent (vol. %) and 3 vol % or between 15 vol % and 16 vol % chromium (Cr), and when present, between 3 at % and 5 at % manganese (Mn), wherein the at least two first elements include aluminum;
between 7 at % and 9 at % phosphorous (P);
no more than three second elements, the second elements being selected from: when present, between 0.5 at % and 4 at % or between 5 at % and 9 at % carbon (C), when present, between 0.1 at % and 1 at % or between 7 at % to 9 at % boron (B), and when present, between 10 at % to 12 at % silicon (Si); and
the balance iron (Fe),
wherein a majority of a structure of the bulk metallic glass alloy is amorphous; and
wherein the alloy has a critical defect size, a c , of no less than 150 μm.
2 . The alloy according to claim 1 , wherein the alloy has a reduced glass transition temperature T rg , defined as T g /T l , of between 0.47 and 0.59.
3 . The alloy according to claim 1 , wherein the alloy has an elastic shear modulus, μ, of between 39 GPa and 82 GPa.
4 . The alloy according to claim 1 , wherein the alloy has a liquidus temperature of from 950° C. to 1450° C.
5 . The alloy according to claim 1 , wherein the alloy has a glass transition temperature of from 355° C. to 630° C.
6 . The alloy according to claim 1 ,
wherein the at least two first elements include zirconium.
7 . The alloy according to claim 1 ,
wherein the at least two first elements include manganese and molybdenum.
8 . The alloy according to claim 1 , the at least two first elements comprising no more than 30 atomic % of the alloy.
9 . The alloy according to claim 8 , the second elements and phosphorous (P) comprising between 10 atomic % and 42 atomic % of the alloy.
10 . The alloy according to claim 1 , wherein between 1 volume percent (vol. %) and 50 vol. % of the structure of the bulk metallic glass alloy is a crystalline metal phase; and
wherein the crystalline metal phase includes at least one of: copper (Cu), aluminum (Al), vanadium (V), chromium (Cr), iron (Fe), and molybdenum (Mo).