Reynolds Metals Company

J Daniel Bryant

Hideo Yoshida

Hidetoshi Uchida

Robert M Ramage

Armand J Beaudoin

Rajeev G Kamat

Alan J Janousek

Stanley Platek

H Edwin Oliver

A method of producing aluminum alloy sheet product includes casting a slab or ingot, homogenizing the cast slab, and hot rolling the homogenized slab to provide an intermediate gauge product. The temperature and other operating parameters of the hot rolling process are controlled so that the temperature of the ingot at the beginning of hot rolling is maintained at a temperature between 925&deg; F. (496&deg; C.) and 1025&deg; F. (552&deg; C.), and the temperature of the intermediate gauge product exiting the hot rolling step is between about 500&deg; F. (260&deg; C.) and 600&deg; F. (316&deg; C.). The intermediate gauge product is then subjected to a cold reduction of 45% to 70%, annealed, and cold rolled to final gauge. The combination of controlling the hot rolling to provide the desired hot line entry temperature and the desired exit temperature of the intermediate gauge product and annealing prior to cold rolling to final gauge minimizes or eliminates the appearance of ridging line defects in the aluminum sheet product when the product is subjected to further straining in a forming operation. An improved aluminum alloy sheet product is produced having a superior surface finish for use in automotive components while maintaining a higher strength than that of the prior art.

Method of making high strength aluminum sheet product and product therefrom

This invention provides a method and apparatus for casting, hot rolling and annealing of non-heat treatable aluminum alloys which comprises continuously casting, hot rolling, and, in-line with the hot rolling line, inductively heating the aluminum sheet. The induction heating system uses a feedback control to assure that the aluminum alloy is heated to the proper temperature based on one or a number of process variables, such as hot rolling exit temperature, hot rolled product exit rate in terms of speed and product dimensions, and sheet temperature at the exit of the induction heater. Variations in the induction heating temperature can be tolerated in the product without deviating from target mechanical properties.

Method and apparatus for casting, hot rolling and annealing non-heat treatment aluminum alloys

A method and apparatus for making aluminum alloy sheet product with improved paintbake response during automotive paintbake cycles, resistance to natural aging and better formability includes rapidly heating the aluminum alloy sheet product between a solution heat treating/quenching operation and a sheet coiling operation. Performing the rapid heating at this stage in the sheet manufacture minimizes the adverse effect of early natural aging (dwell time) on the paintbake response of these types of aluminum sheet alloy products. According to the invention, this dwell time is minimized by the application of a rapid heating step immediately following quenching from the solution heat treatment. After the aluminum sheet product has been rapidly heated, it is immediately coiled and cools under ambient conditions in coil form, this ambient cooling providing a pre-aging treatment which contributes to the improved performance of the sheet product in paintbake response, improved formability and natural aging resistance.

Process and apparatus to enhance the paintbake response and aging

A method of producing aluminum alloy sheet product includes casting a slab, homogenizing the cast slab, and hot rolling the homogenized slab to provide an intermediate gauge product. The temperature and other operating parameters of the hot rolling process are controlled so that the temperature of the intermediate gauge product exiting the hot rolling step is between about 500.degree. F. and 650.degree. F. Preferably, the temperature does not exceed 575.degree. F. The intermediate gauge product is then subjected to a cold reduction of 45% to 70%, annealed, and cold rolled to final gauge. The combination of controlling the hot rolling to provide a desired exit temperature of the intermediate gauge product and annealing prior to cold rolling to final gauge minimizes or eliminates the appearance of ridging or roping line defects in the aluminum sheet product when subjected to further straining in a forming or stamping operation. An improved aluminum alloy sheet product is produced having a superior surface finish for use in automotive components such as hoods or deck lids.

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Midlothian, VA, United States of America

J Daniel Bryant