Kaiser Aluminum

About: Kaiser Aluminum is a based out in . It is known for research contribution in the topics: Alloy & Corrosion. The organization has 546 authors who have published 504 publications receiving 6554 citations. The organization is also known as: Kaiser Aluminum and Chemicals.

Liquid removal device

Abstract: This invention relates to an improved method and device for removing liquid from a moving surface such as a continuous metal sheet or strip. The invention has particular application to the removing of lubricant and/or coolant from sheet or strip in a rolling operation or the backup rolls of the rolling mills. The invention comprises a vacuum unit to remove most of the liquid from the moving surface, an air knife to drive the liquid remaining on the surface toward the vacuum unit, and a vent maintained at a pressure intermediate between the low pressure of the vacuum unit and the high pressure of the air knife to minimize eddy current formation in the gas flow from the air knife to the vacuum unit. Eddy currents can cause the redeposition of liquid onto the essentially dry sheet or strip.

Fracture and fractography of metastable austenites

Abstract: External test variables such as rate and temperature, and changes in alloy composition are shown to have a number of effects on the fracture of high-strength, metastable austenitic steels. One rate-dependent phenomenon is an unusual fracture mode transition wherein a flat mode changes to a shear mode when the amount of transformation product in the vicinity of the crack tip is reduced by adiabatic heating. The point at which this happens in any one test is dependent upon the velocity of the slowly growing crack which in turn is dependent upon the crosshead rate. Because of this rate effect, the plane stress fracture toughness decreases by as much as 30 pct at higher crosshead rates. Fractographically, it was ascertained that at room temperature, both phases failed in a ductile manner, but at −196°C, martensite containing greater than about 0.27 wt pct C would cleave. This resulted in a “ductile-brittle” transition in metastable austenites at −196°C as a function of carbon content. Other compositional variations change the austenite stability which controls the amount of strain-induced marteniste occurring at the crack tip. It is shown that a plane stress fracture toughness (KC) approaching 500,000 psi-in.1/2 may be achieved by decreasing the stability of the austenite. The variation ofKc with austenite stability agrees qualitatively with a theoretical model for the invariant shear contribution to the fracture toughness of metastable austenites.

Preaging effects in Al-Mg-Si alloys

Abstract: The aging characteristics of aluminum alloy extrusions containing 060 to 090 wt pct Mg2Si were determined At low Mg2Si levels, preaging treatments at room temperature and at elevated temperatures refined the GP zone dispersion and increased the alloy’s hardness after final aging Preaging had little effect on hardness at the high end of the Mg2Si range These results are explained on the basis of current aging theories which invoke the concept of a critical temperature, above which homogeneous nucleation does not take place This temperature varies from ≃150°C at 06 pct Mg2Si to ≃220°C at 15 pct Mg2Si The apparent activation energy for final aging was estimated to be 21 kcal/mole, a value which is intermediate between the activation energies for vacancy motion and solute (silicon and magnesium) diffusion in aluminum

A rationalization of factors affecting strength, ductility and toughness of AA6061-type Al–Mg–Si–(Cu) alloys

Abstract: The tensile properties and toughness of AA6061-type alloys (nominally Al–1.0% Mg–0.6% Si–0.3% Cu–0.2% Cr) were characterized in terms of the alloy system’s solubility relationships at the solutionizing temperature. The best combination of strength and ductility is achieved in materials with high soluble Mg 2 Si and excess silicon concentrations. Enhanced ductility at a given strength level is associated with high work hardening rates ( n values), whereas toughness is related to intergranular (IG) fracture tendencies. Toughness is therefore negatively impacted by compositional and processing factors that promote IG precipitation: excess silicon, low solutionizing temperatures, slack quench rates and low dispersoid (Cr/Mn) levels.

A method of manufacturing can body sheet

Abstract: A method for manufacturing aluminum alloy can body stock including a continuous, in-line sequence of hot rolling, annealing and solution heat treating without intermediate cooling and rapid quenching.