Nickel-niobium alloys obtained by picosecond pulsed laser quenching

Ni/sub x/Nb/sub 100-x/ alloys were quenched from the melt by irradiation with a 30 ps Nd:YAG laser pulse with a fluence of about 1 J cm/sup -2/. The crystalline starting materials were multilayered films prepared by d.c. sputtering from alternating elemental targets. For average compositions 40 ≤ chi ≤ 79, the as-deposited films were amorphous and showed the X-ray peak corresponding to the composition modulation. For other compositions, the as-deposited films were microcrystalline. The laser-quenched alloys in the range 23 ≤ chi ≤ 82 were amorphous. This range exceeds that in which amorphous alloys have been prepared by other melt quenching techniques or by sputtering. Laser quenching resulted in glass formation even below the T/sub 0/ line and at intermetallic compound compositions. In the range 0 ≤ chi ≤ 18, homogeneous supersaturated b.c.c. solutions were formed. In the range 89 ≤ chi ≤ 100, homogeneous supersaturated f.c.c. solutions containing twins and stacking faults were formed