January_2021_AMP_Digital

A D V A N C E D M A T E R I A L S & P R O C E S S E S | J A N U A R Y 2 0 2 1 2 8 August, with the first new line expected to be commissioned by May 2013. On September 25, 2011, Alcoa announced a $300 million expansion to automotive sheet production at its Davenport mill in Iowa, again with no mention of Ford. That same month, Ford finally issued the first draft of the new material speci- fications to the suppliers. By October, the new presses for the hydroforming lines were on order, along with the new scrap handling sys- tem. Yet before all of this new equip- ment could be installed, the buildings themselves needed to be refurbished. Dearborn Stamping Plant had opened its doors in 1939, and its windows still carried the blackout paint from WWII. This plant was scheduled to remain an active production site for the existing steel model until the final steel truck was produced at the Kansas City Truck Plant, and so it would be a mixed metal production site until then. During that transition, Dearborn Stamping Plant would only be able to sort the alumi- num scrap three ways, with steel re- placing the fourth stream. Dearborn Stamping Plant had gone through a profound transforma- tion in 2003 when F-150 had come to the Dearborn Truck Plant: All of the original press lines had been removed and replaced by two high-speed trans- fer lines at the south end of the plant. In 2011, the vast expanse between the two transfer lines and the two progres- sive lines in the north end stood empty, ready for what was in fact a rebirth. For the renovation, Ford hired Albert Kahn Associates, the architectural firm that had designed Dearborn Stamping Plant 80 years earlier. Two temporary walls were erected to separate the active site from the construction site. The next step was to establish a 3D CAD mod- el of the plant with detailed 3D scans. The new press lines required new foun- dations, new operating floors, and new electrical, water, and compressed air distribution systems—along with rais- ing the roof by 12 feet. The bill for the upgrades to Dear- born Stamping Plant, Buffalo Stamping Plant, and Dearborn Diversified Man- ufacturing Plant would quickly exceed $400 million, funded in part by a loan from the Department of Energy’s Ad- vanced Technology Vehicles Manufac- turing Loan Program. By June 2011, Ford was testing the first Novelis coil with A951 pretreatment from MSC Wall- bridge. Other manufacturing develop- ment programs were now in full swing, including establishing dimensional tol- erances for thick gauge 6111 parts, han- dling and racking methods for post formed heat treated parts, and statis- tical comparison of material property variability between different suppliers, to name a few. RIVETING CONCERNS The same month also saw the end of the cooperation agreement between Ford and Jaguar Land Rover following its sale to Tata. The AIV teams were now formally separated. The SPR testing workload grew quickly, to the point that some of the work had to be outsourced to Ford’s European research centers in Aachen, Germany. But by November 2011, the two teams were reporting an unexpectedly high level of variability in their SPR results for 6111-T82 post formed heat treated (PFHT) materials. Based on Jaguar Land Rover’s experi- ence with PFHT, the team had expect- ed some limit to the formability of the sheet during the highly-strained SPR process, but a wide range of variability in material was not acceptable. A detailed investigation revealed that Novelis-supplied sheet had much lower ductility during self-piercing riv- eting than the corresponding Alcoa sheet. While Novelis launched an inves- tigation to understand the cause of the problem, the Ford team happily booked the riveting performance offered by the Alcoa sheet and incorporated it into the material specifications. Novelis was now faced with two problems—finding the cause of the variability and improv- ing the riveting performance to match Ford’s new expectations. It was a dif- ficult project because 6111 had been developed as a thin gauge alloy inKings- ton, Ontario, but until the launch of the new lines in Oswego, New York, the only production site for its thick gauge ver- sion was in Nachterstedt, Germany. Development of a car or truck body is divided into two staggered tasks, the underbody and upperbody. One can think of the underbody as a pure engineering exercise that can pro- ceed as soon as the basic architecture is specified. Because the underbody is re- sponsible for many safety and comfort attributes, it is the subject of its own prototype event that Ford calls the M1 build: This build involves a production representative underbody mated to an ad-hoc prototype upperbody, in this case made of modified X1 parts. In con- trast, upperbody development starts in the styling studio after selection of the styling theme; its progress is tied to the maturation of the design in the studio. For P552, engineering of the un- derbody entered the CAE verification phase just before Christmas break and by January 2012, all energy was focused on preparing for the M1 build and relat- edmaterial orders. The convoluted sup- ply routes meant long lead times for the aluminum blanks. With steel and earli- er 5xxx-centric aluminum-intensive ve- hicle body structures, natural aging had never been a concern, but P552 was ma- turing into a largely 6xxx-T4 series proj- ect (Fig. 7). The existing guidelines recognized a six-month shelf life for the T4 materi- al. Thankfully, there were no shelf life issues for the PFHT parts, because they had already undergone artificial aging to T82 temper. The P552 program creat- ed a flood of small orders for laborato- ry testing that would cover a multitude of alloys and thicknesses. The larger or- ders for the various prototype builds came with short delivery schedules and sometimes late engineering changes. For the customer service organizations at Alcoa and Novelis, who were more accustomed to aerospace or can stock, it created an impression of utter cha- os and disorganization. But managing BY JUNE 2011, FORD WAS TESTING THE FIRST NOVELIS COIL WITH A951 PRETREATMENT FROM MSC WALLBRIDGE.