Abstract Changes in the performance of ion-implanted silicon-junction detectors after irradiation with high-energy hadrons produced by 24 GeV/ c protons have been investigated for fluences of up to 8.3 × 10 13 particles cm −2. It was found that in order to be able to use the detector after irradiation, the bias voltage must be increased to obtain full depletion and full charge collection from the intensity disordered small volumes of radiation damage. Also a considerable increase in leakage current was observed. Study of the signals produced by charged particles shows that the detection efficiency after irradiation is not degraded, when the bias voltage has been increased as mentioned above. Because of the greater leakage currents, the noise in the irradiated detectors is increased, leading to a loss in resolution; however, this can be avoided by using fast electronics.