Effect of rolling conditions on the recrystallization and strength of nickel under stress at high temperatures

Abstract

1. The temperatures of the beginning and the end of recrystallization of nickel rolled at 800 and 900°C and quenched are 100° higher than those of nickel rolled at 20°C (swaged 25%). These conditions decrease the recrystallization rate at 600°C, and thus increase the heat resistance of nickel. 2. In nickel rolled at high temperatures with subsequent quenching as well as in nickel rolled at 20°C, the heat resistance at 600°C in vacuum (σ=10 kg/mm2) is higher than the heat resistance of annealed nickel. The time preceding rupture and the time required for 1% elongation increase even when the tests are made at the recrystallization temperature. 3. The recrystallization of rolled nickel at 600°C prevents elongation of the samples at the beginning of the test.