Effect Of Basic Physical Parameters On Engineering Properties Of Intermetallics
Report Number: WADD TR 60-184 Part V
Author(s): Westbrook, J. H., Grenoble, H. E., Wood, D. L.
Corporate Author(s): General Electric Research Laboratory
Laboratory: AF Materials Laboratory
Date of Publication: 1964-03
Pages: 32
Contract: AF 33(616)-7714
DoD Project: 7350
DoD Task: 735001
Identifier: AD0433254
Abstract:
Ingots of nickel-rich NiAl were prepared by induction melting under argon, starting with primary materials of technical grade. Sections cut from these ingots have been hot-rolled to sheet at 1100° to 1200°C by enclosing them in heavy-walled stainless steel containers. Rolled sheet sufficiently free of defects to enable preparation of mechanical test specimens is obtained. Cold-rolling of the hot-rolled sheet can be accomplished at 850°C but requires a heavy reduction (about 30%) in each pass to avoid fracture. Hot-rolled NiAl undergoes a transition to brittle behavior at about 600°C. Below this temperature the mechanical properties are characterized by limited ductility, a sensitivity to surface notches, and by a flow stress that is relatively invariant in respect to temperature. Above 600°C, ductility increases markedly, sensitivity to surface conditions diminishes, and the flow stress becomes strongly temperature dependent. Single crystals do not exhibit a transistion in mechanical behavior and are much weaker and more ductile than polycrystalline material at temperatures below 800°C. Single-crystal rods have been bent at room temperature to a maximum fiber strain of 25% without fracture. Polycrystalline material is of more limited ductility, the maximum fiber strain for fracture at room temperature being a few per cent.Some few observations on the ductile-brittle transistion and other low-temperature properties of the compound AgMg are also included.
Provenance: IIT
Author(s): Westbrook, J. H., Grenoble, H. E., Wood, D. L.
Corporate Author(s): General Electric Research Laboratory
Laboratory: AF Materials Laboratory
Date of Publication: 1964-03
Pages: 32
Contract: AF 33(616)-7714
DoD Project: 7350
DoD Task: 735001
Identifier: AD0433254
Abstract:
Ingots of nickel-rich NiAl were prepared by induction melting under argon, starting with primary materials of technical grade. Sections cut from these ingots have been hot-rolled to sheet at 1100° to 1200°C by enclosing them in heavy-walled stainless steel containers. Rolled sheet sufficiently free of defects to enable preparation of mechanical test specimens is obtained. Cold-rolling of the hot-rolled sheet can be accomplished at 850°C but requires a heavy reduction (about 30%) in each pass to avoid fracture. Hot-rolled NiAl undergoes a transition to brittle behavior at about 600°C. Below this temperature the mechanical properties are characterized by limited ductility, a sensitivity to surface notches, and by a flow stress that is relatively invariant in respect to temperature. Above 600°C, ductility increases markedly, sensitivity to surface conditions diminishes, and the flow stress becomes strongly temperature dependent. Single crystals do not exhibit a transistion in mechanical behavior and are much weaker and more ductile than polycrystalline material at temperatures below 800°C. Single-crystal rods have been bent at room temperature to a maximum fiber strain of 25% without fracture. Polycrystalline material is of more limited ductility, the maximum fiber strain for fracture at room temperature being a few per cent.Some few observations on the ductile-brittle transistion and other low-temperature properties of the compound AgMg are also included.
Provenance: IIT