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Abstract: Thermal tests exposed V–4Cr–4Ti in static liquid lithium at 700 and 800°C for 250, 500, and 1000h. Post-exposure examination included chemical analysis of interstitial impurities in V–4Cr–4Ti to monitor impurity transfer, and tensile tests at room temperature and 500°C. Microstructures were characterized by room-temperature electrical resistivity measurements and transmission electron microscopy. Oxygen was not depleted from V–4Cr–4Ti when nitrogen pickup occurred during lithium exposures. In spite of a significant increase in interstitial impurity concentration, the matrix interstitial solute content was reduced due to precipitation. Plate-shaped precipitates in the matrix and globular precipitates at grain boundaries were formed during lithium exposures at 700°C, while only globular precipitates were observed at grain boundaries at 800°C. Increases in strength, decreases in ductility, and reduced dynamic strain aging resulted. Ductility remained high after 1000h exposures at both 700 and 800°C. [Copyright &y& Elsevier]