The ‘Progress in the ITER Physics Basis’ (PIPB) document is an update of the ‘ITER Physics Basis’ (IPB), which was published in 1999 [1]. The IPB provided methodologies for projecting the performance of burning plasmas, developed largely through coordinated experimental, modelling and theoretical activities carried out on today's large tokamaks (ITER Physics R&D). In the IPB, projections for ITER (1998 Design) were also presented. The IPB also pointed out some outstanding issues. These issues have been addressed by the Participant Teams of ITER (the European Union, Japan, Russia and the USA), for which International Tokamak Physics Activities (ITPA) provided a forum of scientists, focusing on open issues pointed out in the IPB. The new methodologies of projection and control are applied to ITER, which was redesigned under revised technical objectives. These analyses suggest that the achievement of Q > 10 in the inductive operation is feasible. Further, improved confinement and beta observed with low shear (= high βp = ‘hybrid’) operation scenarios, if achieved in ITER, could provide attractive scenarios with high Q (> 10), long pulse (>1000 s) operation with beta

We report a new process which promises high critical current density in oxide superconductors. The process consists of three stages. Firstly a YBa2Cu3O x sample is rapidly heated and quenched from the Y2O3 plus liquid region. Subsequently the quenched sample is reheated to the Y2BaCuO5 plus liquid region, and then slowly cooled with a temperature gradient in flowing oxygen. The process enables us to grow a superconducting phase unidirectionally and to suppress the second phase intrusion, leading to the production of well textured YBa2Cu3O x which yields a high J c value in the presence of magnetic fields. It is also found that Bean's critical state is realized in such high J c samples.

Structural alteratiolls due to rollillg contact fatigue are investigated microscopically fo r two bearing sleels i. e. a S UJ-2 (A1S1 52100) steel alld a O.65% C steel. T wo tylJeS q! structural alteration, the white etching constituent and the dark etching Olle, are revealed. The former originates at nonmetallic inclusions, mostly at alumina, and a microcrack is q{ten seen to be associated with it. The white etelzing constituents grow in number and size with I'epeated C)'cles, but are suppressed at the delJth where the dark etching zone fo rms. T his delJth also corresp onds to that where shear stress becomes maximum. E ach dark etching constituent of which the dark etch• ing zone is made is a variation of original martensite leaves. The hardness of the dark etching constituent is lower than that of the original martensite. The mechanism of the decomposition of martensite is discussed.

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Trapped magnetic flux density of melt-grown YBaCuO bulk superconductors was evaluated. A single-grained disc-shaped bulk sample with a size of 45 mmφ×15 mm trapped very high magnetic flux density after field cooling. One disc trapped a maximum surface flux density of 0.72 T, while the maximum of double-piled discs was 1.35 T after 100 seconds. A polygrained sample showed a much lower maximum. The pinning potential of this single-grained disc was 0.17 eV, and the overall critical current density estimated from the trapped flux density was about 7×103 A/cm2. Since these values are lower than those of a small-sized sample, weak links are still expected to exist even in the single-grained sample. Domain structure within a grain is a strong candidate for this weak link.