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Rare earths are a group of elements whose availability has been of concern due to monopolistic supply conditions and environmentally unsustainable mining practices. To evaluate the risks of rare earths availability to automakers, a first step is to determine raw material content and value in vehicles. This task is challenging because rare earth elements are used in small quantities, in a large number of components, and by suppliers far upstream in the supply chain. For this work, data on rare earth content reported by vehicle parts suppliers was assessed to estimate the rare earth usage of a typical conventional gasoline engine midsize sedan and a full hybrid sedan. Parts were selected from a large set of reported parts to build a hypothetical typical mid-size sedan. Estimates of rare earth content for vehicles with alternative powertrain and battery technologies were made based on the available parts' data.

In today's highly competitive automotive markets manufacturers must provide high quality products to survive. Manufacturers can achieve higher levels of quality by changing or improving their manufacturing process and/or by product inspection where many strategies with different cost implications are often available. Cost of Quality (CoQ) reconciles the competing objectives of quality maximization and cost minimization and serves as a useful framework for comparing available manufacturing process and inspection alternatives. In this paper, an analytic CoQ framework is discussed and some key findings are demonstrated using a set of basic inspection strategy scenarios. A case of a welded automotive assembly is chosen to explore the CoQ tradeoffs in inspection strategy selection and the value of welding process improvement. In the assembly process, many individual components are welded in series and each weld is inspected for quality.

FutureSteelVehicle’s (FSV) objective is to develop detailed design concepts for a radically different steel body structure for a compact Battery Electric Vehicle (BEV). It also will identify structure changes to accommodate larger Plug-In Hybrid (PHEV) and Fuel Cell (FCEV) vehicle variants. The paper will demonstrate seven optimised structural sub-systems that contribute to the programme's 35 percent mass reduction goals and meet its safety and life cycle emissions targets. It will explain the advanced design optimisation process used and the resulting aggressive steel concepts.

The ability to make accurate decisions concerning early body-in-white architectures is critical to an automaker since these decisions often have long term cost and weight impacts. We address this need with a methodology which can be used to assist in body architecture decisions using process-based technical cost modeling (TCM) as a filter to evaluate alternate designs. Despite the data limitations of early design concepts, TCM can be used to identify key trends for cost-effectiveness between design variants. A compact body-in-white architecture will be used as a case study to illustrate this technique. The baseline steel structure will be compared to several alternate aluminum intensive structures in the context of production volume.

A 2001 SAE paper et al. [1,2] compared the formability aspects of six different grades of galvanealed steel [IF (270E), C-Mn (440W-1), low C - high Mn (440W-2), HSLA440 (440R), HSLA590 (590R) and DP590 (590Y)]. This study has been expanded to evaluate five additional advanced galvanealed steel grades [Low yield type DP780 (780YL), High yield type DP780 (780YM), DP980 (980Y), TRIP590 (590T), and TRIP780 (780T)]. The study presents material properties, forming characteristics in several lab tests and spring back characteristics. The study provides the actual and relative performance of these eleven steels and conclusions on the advantages these grades provide in cost-effective and mass-effective solutions to the manufacturing and performance requirements of the automotive body.

Advanced high strength steels were a key enabling factor in achieving the remarkable results of the ULSAB-AVC (Advanced Vehicle Concepts) Program. The complete body structure consists of high strength steels with over 80% being advanced high strength steel grades. Vehicle weight reduction, reduced costs and improved safety performance are the main driving forces behind material selection for automotive applications. High strength steels (HSS) have demonstrated their ability to meet these demands and consequently have been the fastest growing light-weighting material in vehicle structures for the past decade. The evolution in steel technology in recent years has produced new grades of highly formable, advanced high strength steel (AHSS) grades that will continue to meet these automotive demands into the next decade.

Vehicle weight reduction, reduced costs and improved safety performance are the main driving forces behind material selection for automotive applications. High strength steels (HSS) have demonstrated their ability to meet these demands and consequently have been the fastest growing light-weighting material in vehicle structures for the past decade. The evolution in steel technology in recent years has produced new grades of highly formable, advanced high strength steel (AHSS) grades that will continue to meet these automotive demands into the next decade. This paper provides an example of how these advanced automotive materials have been incorporated into the ULSAB-Advance Vehicle Concept (ULSAB-AVC) and how these materials enable cost- and mass-effective solutions that satisfy the increasing crash performance requirements placed on vehicle designs.

Vehicle weight reduction, reduced costs and improved safety performance are the main driving forces behind material selection for automotive applications. These goals are conflicting in nature and solutions will be realized by innovative design, advanced material processing and advanced materials. Advanced high strength steels are engineered materials that provide a remarkable combination of formability, strength, ductility, durability, strain-rate sensitivity and strain hardening characteristics essential to meeting the goals of automotive design. These characteristics act as enablers to cost- and mass-effective solutions. The ULSAB-AVC program demonstrates a solution to these conflicting goals and the advantages that are possible with the utilization of the advance high strength steels and provides a prediction of the material content of future body structures.

In this study, comparisons are made of the crash energy performance between five grades of steel, including conventional mild steel, conventional HSS, and several grades of advanced HSS including Dual Phase 590Y. The influence of processing effects, work hardening and bake hardening, are also evaluated. Simple closed hat channels are formed by two methods, the first with minimum work hardening, the second with work and bake hardening. These hat channels are then subjected to a drop test at 25 km/hr and 50 km/hr. The load and deflection are recorded for each case and comparisons are made.

The objective of the research presented in this paper was to assess the influence of stamping process on crash response of UltraLight Steel Auto Body (ULSAB) [1] vehicle. Considered forming effects included thickness variations and plastic strain hardening imparted in the part forming process. The as-formed thickness and plastic strain for front crash parts were used as input data for vehicle crash analysis. Differences in structural performance between crash models with and without forming data were analyzed in order to determine the effects and feasibility of integration of forming processes and crash models.

The remarkable evolution of steel technology in recent years has resulted in the development of new High Strength Steels (HSS) that are increasingly used in today's automobiles. The advanced performance of these grades in ductility and rapid hardening characteristics provides an opportunity to stamp complex geometries with in-panel material strengths far exceeding those of conventional high strength grades of steel. This provides an opportunity to improve an automotive body's performance in crash, durability and strength while reducing the overall weight of the vehicle. An improved understanding of the forming characteristics of these advanced HSS and accurate prediction of the material processing strain will allow vehicle designers to fully explore the opportunities of increased yield, strain hardening, formability and strength and the potential this creates to reduce mass and improve the performance of the automotive body.

This paper describes the results of the computational analysis of UltraLight Steel Auto Body (ULSAB) crash simulations that were performed using advanced material modeling techniques. The effects of strain-rate sensitivity on a high strength steel intensive vehicle was analyzed. Frontal and frontal offset crash scenarios were used in a finite element parametric study of the ULSAB body structure. Comparisons are made between the crash results using the piece-wise-linear isotropic plasticity strain-rate dependent material model, and the isotropic plasticity material model based on quasi-static properties. The simulation results show the importance of advanced material modeling techniques for vehicle crash simulations due to strain-rate sensitivity and rapid hardening characteristics of advanced high strength steels.

Autokinetics is a Rochester Hills MI design firm working with Armco, a supplier of stainless steel. Together, they have developed an architecture that replaces the traditional stamped and spot welded steel unibody with a novel stainless steel spaceframe architecture. Fabrication Rollformings Thin wall castings Progressive die stampings Plastic support and exterior panels Assembly - Spot, laser, and MIG welding Relative to conventional steel unibodies, the Autokinetics spaceframe architecture offers a number of projected advantages. Substantial mass reduction Increased safety Improved ride and NVH More flexible packaging Lower lifecycle impact Potential for paint shop elimination The obvious question that arises, and the one that this paper will answer, is: How does the Autokinetics spaceframe architecture compete on cost?

With the increased focus on weight reduction in automotive body-in-white panels, laser welded blanks (LWB) have been embraced in the design of major body panels and closures. Current applications for laser welded blanks generally consist of two differently gaged blanks combined via a linear weld line. Advancing technology now offers opportunities to incorporate nonlinear weld lines and part configurations of more than two blanks. This study shows how a liftgate inner panel featuring non-linear laser weld lines can be designed, which will decrease weight and cost, and improve stiffness performance.

Low volume manufacturing has become increasingly important for the automotive industry. Globalization trends have led automakers and their suppliers to operate in developing regions where minimum efficient scales can not always be achieved. With proper maintenance, standard cast iron stamping tools can be used to produce millions of parts, but require large investments. Thus at high production volumes, the impact of the tooling investment on individual piece costs is minimized. However, at low volumes there is a substantial cost penalty. In light of the trends towards localized manufacturing and relatively low demands in some developing markets, low cost stamping tools are needed. Several alternate tooling technologies exist, each of which require significantly lower initial investments, but suffer from greatly reduced tool lives. However, the use of these technologies at intermediate to high volumes requires multiple tool sets thus eliminating their cost advantage.

Recent industry trends have resulted in growing interest among automakers in low to medium volume manufacturing. The expansion of automobile production into developing economies and the desire to produce specialized vehicles for niche markets have pressed the automakers to find cost effective solutions for manufacturing at low volumes, particularly with regard to sheet metal forming. Conventional high volume stamping operations rely heavily on achieving minimum scale economies which occur at about 200,000 parts per year. These scale economies are mainly dictated by the efficient use of the standard, expensive cast iron dies. These dies can cost well over one million dollars depending on the part, and in return offer tool lives over 5 million strokes. Die investment can be reduced by changing the stamping process technology. Hydro-mechanical forming has been proposed as a promising low volume alternative to conventional stamping.

Aluminum and polymer composites have long been considered the materials of choice for achieving mass reduction in automotive structures. As consumer and government demand for mass reduction grows, the use of these materials, which have traditionally been more expensive than the incumbent steel, becomes more likely. In response to this growing challenge, the international steel community has joined forces to develop the Ultra Light Steel Auto Body (ULSAB). The resulting design saves mass and increases performance relative to current steel unibodies. Although mass savings are not as dramatic as those achieved by alternative materials, this design offers the potential to be accompanied by a manufacturing cost reduction. The projected manufacturing piece and investment cost for the ULSAB are investigated using technical cost modeling. The results presented here examine the elements that contribute to the cost, including treatments for stamping, hydroforming, assembly and purchased parts.

In the past decade, the demand for and development of tailor-welded blanks (TWBs) has increased dramatically. TWBs help reduce body mass, piece count and assembly costs, while potentially reducing overall cost. IBIS Associates, Inc. has performed a cost analysis of tailor welded blank manufacturing through the use of Technical Cost Modeling (TCM), a methodology used to simulate fabrication and assembly processes. IBIS has chosen the automobile door inner panel for comparison of TWBs and conventionally stamped door inners with added reinforcements. Manufacturing costs are broken down by operation for variable costs (material, direct labor, utility), and fixed costs (equipment, tooling, building, overhead labor, maintenance, and cost of capital). Analyses yield information valuable to process selection by comparing cost as a function of manufacturing method, process yield, production volume, and process rate.

Hyrdroformed tubes have seen use in the aerospace industry for many years and are seeing increased use in the automotive body-in-white (BIW). The automotive industry has chosen to use hydroformings for a number of reasons including reduced part weight, piece count reduction, and the flexibility to form complex shapes of varying wall thickness. With all of these potential advantages, still one more provides the greatest incentive to switch from a stamped assembly to a hydroformed tube: the ability to reduce cost. It is generally accepted that hydroformings can indeed be cost effective to produce, yet the question remains: when should a stamped assembly be replaced by a hydroformed component? This paper will attempt to answer the question above by laying out several case studies and comparing their direct manufacturing costs.

Despite repeated challenges from alternative materials and processes, the stamped and spot welded steel unibody remains the near-unanimous choice of automakers for vehicle body-in-white (BIW) structures and exterior panels in volume production. Conventional steel's only weakness is mass; aluminum and polymer composites offer the potential for considerable mass savings, but generally at a higher cost. Efforts within the automakers as well as by outside organizations such as the international steel industry's Ultra Light Steel Auto Body (ULSAB) program are underway to improve the steel uni-body's mass and cost position. To reduce cost, it is first necessary to identify cost. The measurement of cost for a complex system such as an automobile BIW is far from a trivial task. This paper presents an analytical approach to understanding the manufacturing cost for a conventional steel unibody. The results of this cost analysis are then used to outline a strategy for future cost reduction.