Patent ID: 8419869

Claim:
A method comprising: supplying a metal alloy comprising Fe at a level of 65.5 to 80.9 atomic percent, Ni at 1.7 to 15.1 atomic percent, B at 3.5 to 5.9 atomic percent, Si at 4.4 to 8.6 atomic percent; melting said alloy and solidifying to provide a matrix grain size of 500 nm to 20,000 nm and a boride grain size of 25 nm to 500 nm; mechanical stressing said alloy and/or heating to form at least one of the following grain size distributions and mechanical property profiles, wherein said boride grains provide pinning phases that resist coarsening of said matrix grains: (a) matrix grain size of 500 nm to 20,000 nm, boride grain size of 25 nm to 500 nm, precipitation grain size of 1 nm to 200 nm wherein said alloy indicates a yield strength of 300 MPa to 840 MPa, tensile strength of 630 MPa to 1100 MPa and tensile elongation of 10 to 40%; or (b) refined matrix grain size of 100 nm to 2000 nm, precipitation grain size of 1 nm to 200 nm, boride grain size of 200 nm to 2,500 nm where the alloy has a yield strength of 300 MPa to 600 MPa.