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The aim of this analysis was to model the effect of adding stiffening ribs in structural aluminum components by friction stir processing (FSP) Nano material into the aluminum matrix. These stiffening ribs could dampen, redirect, or otherwise alter the transmission of energy waves created from automotive, ballistic, or blast shocks to improve noise, vibration, and harshness (NVH) and structural integrity (reduced joint stress) response. Since the ribs are not created by geometry changes they can be space efficient and deflect blast / ballistic energy better than geometry ribbing, resulting in a lighter weight solution. The blast and ballistic performance of different FSP rib patterns in AL 5182 and AL 7075 were simulated and compared to the performance of an equivalent weight of RHA plate FSP helps to increase localized strength and stiffness of the base metal, while achieving light weighting of the base metal.

The recently published Lightweight Combat Vehicle Science and Technology Campaign [1] recommended the Army develop a quantitative understanding of the operational impact that weight reduction has to the Army and create appropriate metrics that would better reflect the performance trade with regards to weight. That paper raised the question of what a ton of weight is worth in operational effectiveness and cost. This paper is an attempt to clarify this complex topic. The impact of select programmatic considerations, operational considerations, and financial considerations are discussed. Throughout, the paper provides example analyses based on vehicle weight, performance, and cost data. The paper closes with a discussion of the issues presented, research recommendations, and closing comments.

Fe-Mn-Al-C steel alloys have been previously studied for their potential as an alternative steel alloy for Rolled Homogeneous Armor (RHA). Prior examination of the material system has shown promise in this capacity due to the high strength and reduced density of Mn steels as compared to RHA. The prior tested materials were both wrought and cast versions but were all less than an inch in thickness. The alloy is once again being examined, but this time in thicker wrought plate. The aim of the current body of work is to develop a Military Specification (MIL-SPEC) for this new class of ballistically capable material. For industry and communities interested in such material development, the purpose of this paper, then, is to provide a summary of the processing parameters, the prior ballistic and dynamic material testing, cutting and welding approaches, and the extent of progress on industrial sized thick plate development.

Functional build (FB) is a critical process in launching a vehicle, whereby individual prototype parts are stamped and then sent to a central location to be assembled into a prototype vehicle body. FB is a manufacturing strategy which states that if the dimensional quality of parts, and sub-assemblies are assessed within the context of the final assembly, then fewer and lower cost engineering changes are required to achieve a saleable product. This paper describes Virtual Functional Build (VFB) where scanned parts are assembled virtually using assembly modeling software. Finite element analysis technology is used to deform the scanned parts to the shape that they would adopt on the FB tooling. The potential benefits of VFB over traditional FB techniques are reduced capital investment in tooling and, more importantly, reduced lead time due to earlier collaboration between geographically remote part and sub-assembly suppliers.

A comparative benchmarking study of the dimensional door quality 14 vehicles from Ford, General Motors, Daimler-Chrysler, Toyota, Nissan, BMW, Volvo, and Renault was conducted. Various aspects of the door design, manufacturing, assembly and hanging system were studied. This paper focuses on the dimensional quality of the doors and relates it to the final vehicle quality in terms of gaps and flush as well as customer satisfaction as established by J. D. Power Initial Quality Survey (IQS). For confidentiality reasons, all vehicles in the study are referred to by a coded designation.

This paper discusses the results of a door benchmark study performed on 14 vehicles. The major focus is on the selection of datums or reference points and its impact on the product quality of the door system. The results indicate that there can be a relationship between datum utilization and quality metrics at any stage in the production process. Specific examples show the impact of various strategies on product performance.