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Regulatory requirements and key market drivers are shaping design trends for smarter, safer, quieter and more energy-efficient vehicle technologies with steadily less environmental impact. Among vehicle powertrain enhancements to increase [...]

In regard to your January article on the 2020 Toyota Supra, imagine the developers' surprise when they removed the now-famous multicolor triangular camouflage from the car and found they had [...]

Refractory materials, in particular tungsten base materials are considered as primary candidates for structural high heat load applications in future nuclear fusion power plants. Promising helium-cooled divertor design outlines make use of their high heat conductivity and strength. The upper operating temperature limit is mainly defined by the onset of recrystallization but also by loss of creep strength. The lower operating temperature range is restricted by the use of steel parts for the in- and outlets as well as for the back-bone. Therefore, the most critical issue of tungsten materials in connection with structural divertor applications is the ductile-to-brittle transition. Another problem consists in the fact that especially refractory alloys show a strong correlation between microstructure and their manufacturing history. Since physical and mechanical properties are influenced by the underlying microstructure, refractory alloys can behave quite different, even if their chemical composition is the same. Therefore, creep and thermal conductivity have been investigated using typical commercial tungsten materials. Moreover, the fracture behavior of different tungsten based semi-finished products was characterized by standard Charpy tests which have been performed up to 1100 °C in vacuum. Due to their fabrication history (powder mixing, pressing, sintering, rolling, forging, or swaging) these materials have specific microstructures which lead different fracture modes. The influence of the microstructure characteristics like grain size, anisotropy, texture, or chemical composition has been studied.

Refractory materials, in particular tungsten base materials are considered as primary candidates for structural high heat load applications in future nuclear fusion power plants. Promising helium-cooled divertor design outlines make use of their high heat conductivity and strength. The upper operating temperature limit is mainly defined by the onset of recrystallization but also by loss of creep strength. The lower operating temperature range is restricted by the use of steel parts for the in- and outlets as well as for the back-bone. Therefore, the most critical issue of tungsten materials in connection with structural divertor applications is the ductile-to-brittle transition. Another problem consists in the fact that especially refractory alloys show a strong correlation between microstructure and their manufacturing history. Since physical and mechanical properties are influenced by the underlying microstructure, refractory alloys can behave quite different, even if their chemical composition is the same. Therefore, creep and thermal conductivity have been investigated using typical commercial tungsten materials. Moreover, the fracture behavior of different tungsten based semi-finished products was characterized by standard Charpy tests which have been performed up to 1100 °C in vacuum. Due to their fabrication history (powder mixing, pressing, sintering, rolling, forging, or swaging) these materials have specific microstructures which lead different fracture modes. The influence of the microstructure characteristics like grain size, anisotropy, texture, or chemical composition has been studied.

Human variation in motor abilities and genetic analysisRudolf Kovar, Charles University, Prague, 1981 178 pp (pb), ISBN 40 024 81American Academy of Orthopaedic Surgeons' Symposium on 'The foot and leg in running sports'Robert P. Mack (ed.), C.V. Mosby Co., St. Louis, 1982 184 pp, 118 illustrations, £31 (hb), ISBN 0 8016 0054 5KinesiologyJ.M. Cooper, M. Adrian and R.B. Glassow, C.V. Mosby, London, 1982 452 pp, £16.50 (hb), fifth edition, ISBN 0 8016 1040 0Training for sport and activityJack H. Wilmore, Allyn and Bacon Inc., Boston and London 294 pp, £10.95 (hb), ISBN 0 205 07761 7