[en] Practical electromechanical properties of a high-T_c superconductor have been measured for Ag-sheathed Bi₂Sr₂Ca₁Cu₂O_8+x superconductors at high magnetic fields up to 25 T. A melt-processed powder-in-tube Bi₂Sr₂Ca₁Cu₂O_8+x conductor had an irreversible strain of 0.2% for the onset of permanent damage and a 50% critical-current-degradation strain of 0.36%. Measurements of a discontinuous filament melt-processed Ag-sheathed Bi₂Sr₂Ca₁Cu₂O_8+x superconductor show an irreversible strain of 0.6% and a 50% degradation strain of about 1%. These strain damage thresholds are about an order of magnitude higher than for high-temperature superconductors made by bulk sintering and are reaching practical values of magnet design