Abstract: A method of tailoring the heat balance of the outer edge of the dendrites adjacent the meniscus to produce thinner, smoother dendrites, which have substantially less dislocation sources contiguous with the dendrites, by changing the view factor to reduce radiation cooling or by irradiating the dendrites with light from a quartz lamp or a laser to raise the temperature of the dendrites.

Abstract: An alloy consisting essentially of from about 14% to 19% chromium, from 25 to 35% of nickel, from about 2% to 3% molybdenum, from about 0.1% to 1% of silicon, up to 0.5% of manganese, from about 0.03 to 0.05% carbon, up to about 0.01% sulfur, up to about 0.01% of phosphorus, up to 0.01% boron, up to about 0.01% oxygen, up to about 0.02% nitrogen, small amounts of incidental impurities, and the balance being iron, the alloy having an N.sub.v (average electron vacancy number) value of between 1.6 and 2.8, has an unexpected combination of properties enabling it to be formed by hot and cold working and heat treatment into components and members particularly suitable for use in nuclear reactors wherein the components are subjected to molten sodium, where the corrosion of the surface of the alloy is not in excess of the order of 1 to 2 mils per year, and the alloy exhibits low swelling when exposed to intense radiation, while exhibiting good physical properties at temperatures of up to 1325.degree. F.