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This paper summarizes the work on the manufacturing and testing of conductor samples for ITER poloidal field 1&6 coils. The work was carried out by the IO and multiple institutions in the EU, Switzerland and Russia. Five samples were manufactured and tested in the SULTAN test facility. Analyses of dc performances, ac, and mechanical losses test results have been performed. All measurements were carried out before and after cyclic mechanical load created by the electromagnetic forces. DC test results of all samples tested demonstrated that the conductor performances are not affected by cycling mechanical load and meet the required value of current-sharing temperature $T_{{\rm{cs}}}\geq $ 5.8 K at magnetic field $B_{{{\max}}}\,= $ 6.4 T and operating current $I_{{\rm{op}}}\,= $ 48 kA. Measurements of the ac and mechanical losses were performed by gas flow calorimetric method. AC loss measurements were carried out at different operating currents and background magnetic fields. AC loss of tested samples showed no change under cycling mechanical load, but showed a correlation of ac loss versus background magnetic field. Mechanical loss, as had been expected, decreased significantly after first ten cycles then reaches a stabile value. The value of mechanical loss even in virgin condition does not affect workability of a magnet. [ABSTRACT FROM PUBLISHER]

AC loss of \Nb3\Sn cable-in-conduit conductors (CICC) decreases after cyclic mechanical loading, but remains almost the same in case of Nb-Ti ones. It was observed during previous ITER CS, TF, and PF inserts tests in JAEA. The same phenomena have been detected on numerous ITER CS, TF, and PF short samples tested in the SULTAN facility. Experimental methods of ac loss investigation in JAEA-Naka and SULTAN were different, but the final results showed a good agreement. Analysis and numerical investigation of the present work were based on RF PF&TF CICCs SULTAN test results, theory of superconductivity, and our own physical and engineering understanding of evidence. Cyclic mechanical loading in both JAEA and SULTAN was initiated by electromagnetic force. In this paper, we attempt to explain why hysteresis, coupling, and mechanical loss decrease dramatically after cyclic mechanical loading and thermo-mechanical stress caused by WUCD (warm-up and cool-down) in \Nb3\Sn CICC. [ABSTRACT FROM PUBLISHER]