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Automotive design is a process which applies multidisciplinary and engineering knowledge to originate and develop plans or concepts for a new type of automotive or its modificaton. The automotive design employs the whole spectrum of engineering knowledge and know-how. Among them, the experimental mechanics plays an important role. In this survey, the recent development of experimental mechanics and how it contributes to automotive design is conducted. Firstly, the prestress engineering technology for mechanical design is introduced. In details, how to generate the prestress, determine its value and apply it in design are presented. Extending this a little bit, how to predict fatigue life based on cyclic stresses is also included. Secondly, the concept of surface nanocrystalization and how it improves material properties are articulated. Finally, the potential applications of this technology in automotive industry is predicted.

Many research projects have been conducted recently in the field of residual stress. But very few projects are relative to design with residual stress problems. Within the European Network for Surface and Prestress Engineering and Design (ENSPED) with 18 partners (including Volvo, Fiat, Bosch etc.), we promote a global approach (material, processing and mechanical design) to prestress engineering. This paper presents a overview of one part of results carried out by the University of Technology of Troyes within this project.

This paper presents a fatigue design tool for three dimensional components with taking the residual stresses into account. The residual stresses are present in many mechanical components and play an important role in the fatigue problem of structure. By using the cyclic behaviors of material, a simplified method to calculate residual stress relaxation has been proposed in the first part of this paper. Secondly, a method to predict fatigue life with taking the stabilized residual stresses into account is presented. This design tool is based on the finite element method. It has been applied to shot-peened 35NCD16 grade steel. The different fatigue parameters often used in material research are studied. An experimental investigation about this material had been done by Bignonnet[1]. The results of study show that this design tool on fatigue developed by LASMIS[2] is able to take into account different loading parameters.

This study qualitatively examines pressure exchange, fluid flow and charge trapping in the combustion process of I.C. engines in which Sonex micro-chamber cavities have been imbedded inside the walls of the piston bowl. The geometry of these micro-chambers serves to generate intermediate chemical species and radicals by quenching the flame in the passages connecting the micro-chambers to the piston bowl, thus allowing incomplete combustion of the charge trapped inside the cavities. It is established from experimentation that, when the products of this incomplete combustion are then allowed to mix with the fresh charge of the next cycle in the main chamber, there is a significant change in the chemical kinetics of the main chamber combustion. The overall combustion process can be made to operate with good stability at substantially lower ignition temperatures and leaner air-fuel ratios than normal … resulting in an ultra-clean exhaust.

A Tuskegee University research team has developed paper from inedible sweetpotato (Ipomoea batatas), peanut (Arachis hypogea), and soybean (Glycine max) plant residues for NASA's Advanced Life Support Program (ALS) for sustaining human life in space. The objective was to develop papers that could be used as a media for inocula and characterize their physical and mechanical properties. The tensile fracture behavior, micromorphological analysis, and fracture surface examination of peanut shells, sweetpotato stems, soybean pods, and a combination of sweetpotato stems (60%) / peanut shells (40%) papers were also investigated. The ultimate strength was 2.6 MPa, 9.2 MPa, 7.1 MPa and 6.5 MPa, respectively. All samples performed well as a media inocula.

Fundamental knowledge concerning how thermoplastic polyolefins (TPOs) fail under impact fracture conditions is lacking. Approaches for gaining such knowledge are proposed. The fracture mechanisms in a variety of experimental and commercially available thermoplastic olefins (TPO) blends are investigated using the double-notch four-point-bend Charpy impact test. It is shown that the operative impact fracture mechanisms and the size of the damage zone in TPO blends depend strongly on the impact modifiers utilized. Strategy for improving low temperature impact strength of TPOs is discussed.