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A new wheel end concept was designed and developed to allow sport utility vehicles (SUV) and light trucks the possibility of achieving a negative scrub radius. This paper will compare a production vehicle with a scrub radius of 54.8 mm with the same vehicle modified with several alternate scrub radii. The vehicle changes are completed in a way that still packages the brake components and meets the component durability needs of a light truck wheel end load cycle. Quantitative vehicle computer analysis and actual instrumented vehicle performance data will be compared and correlated to analyze the effects of scrub radius.

Fatigue testing of components is used to validate new product designs as well as changes made to existing designs. On new designs it is common to initially test parts at the design stage (design verification or DV) and then again at the production stage (production verification or PV) to make sure the performance has not changed. On changes to existing designs typically the life of the new part (B) is compared to that of the old part (A). When comparing the fatigue life Weibull analysis is normally used to evaluate the data. The expectation is that the B10 or B50 life of the new part or PV parts should be equal to or better than that of the old parts or the DV parts. However, fatigue testing has a great deal of inherent variability in the resulting life. In this paper the variability of numerous carburized and induction hardened components is examined.

The effect of multiple braze furnace exposures has been questioned by many because the rework of brazed parts is a common practice in manufacturing. However, there are process controls that limit the number of exposures for an assembly due to known issues with multiple exposures. A common concern deals with the effect of multiple braze furnace exposures on the structural integrity of the base material of the components. Another concern regards the effect of multiple exposures on the structural integrity of the braze joint itself. This paper details experimental results of a physical study to investigate these questions. The material forms used are seam-welded tube and a thin-wall stamped component, both made from 304L stainless steel. The copper paste used in the study has an industry designation of ANSI/AWS A5.8 - BCu-1a.

Locati method is suitable in preliminary fatigue tests and production quality control. It is efficient since it uses just one test sample. The method requires that the slope of the S-N curve be known a priori, however. In this paper, a modified Locati method is presented that virtually eliminated this requirement. The method produces a point on the S-N plane that is independent of the slope of the S-N curve. The test design strategy to control the fatigue life of such a point is provided. The presented method has been successfully applied to preliminary fatigue tests of several welded components of ground vehicles.

This paper discusses the virtual development process used to support design of a high-tonnage hydroform press. It also discusses the optimized design for structural integrity while achieving low target cost. Other considerations included optimization of setup issues such as press fabrication and assembly. Due to tightly constrained development time, a diverse range of CAE methodologies were used to refine and validate the design. Detailed linear and nonlinear finite element models were developed to provide the required accuracy in the critical regions of the press structure. From these detailed models simplified analytical tools were developed to calculate the key press parameters such as alternating stress and predicted fatigue life. Finite element models were validated with physical strain gage measurements from an array of strain gages installed on the production presses.