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The concepts of Verification and Validation (V&V) can be oversimplified in a succinct manner by saying that “verification is doing things right” and “validation is doing the right thing”. In the world of the Finite Element Method (FEM) and computational analysis, it is sometimes said “verification means solving the equations right” and “validation means solving the right equations”. In other words, if one intends to give an answer to the equation “2+2=”, then one must run the resulting code to assure that the answer “4” results. However, if the nature of the physics or engineering problem being addressed with this code is multiplicative rather than additive, then even though Verification may succeed (2+2=4 etc), Validation will fail because the equations coded are not those needed to address the real world (multiplicative) problem.

Design for Six Sigma (DFSS) has evolved as a worthy predecessor to the application of Six-Sigma principles to production, process control, and quality. At Lawrence Livermore National Laboratory (LLNL), we are exploring the interrelation of our current research, development, and design safety standards as they would relate to the principles of DFSS and Six-Sigma. We have had success in prioritization of research and design using a quantitative scalar metric for value, so we further explore the use of scalar metrics to represent the outcome of our use of the DFSS process. We use the design of an automotive component as an example of combining DFSS metrics into a scalar decision quantity. We then extend this concept to a high-priority, personnel safety example representing work that is toward the mature end of DFSS, and begins the transition into Six-Sigma for safety assessments in a production process.

This work compares the relative importance of material anisotropy in sheet forming as compared to other material and process variables. The comparison is made quantitative by the use of normalized dependencies of depth to failure (forming limit is reached) on various measures of anisotropy, as well as strain and rate sensitivity, friction, and tooling. Comparisons are made for a variety of forming processes examined previously in the literature as well as two examples of complex stampings in this work. The examples cover a range from nearly pure draw to nearly pure stretch situations, and show that for materials following a quadratic yield criterion, anisotropy is among the most sensitive parameters influencing formability. For materials following higher-exponent yield criteria, the dependency is milder but is still of the order of most other process parameters.