Many Ni-base single crystal superalloys were developed as a structural material in the hot sections of the jet engine, etc. However, relative comparison of their mechanical properties is usually difficult, due to the difference of the manufacturing processes and the test conditions. Then, we have tried to make the database of the creep properties obtained on as same manufacturing process and testing condition as possible for commercial alloys.
   In this study, the creep rupture tests were examined for RenéN4, RenéN5 and CMSX-4 SC alloys, which were cast by using our directionally solidified casting furnace. The temperature/stress conditions of the creep tests were settled in the range from 900°C to 1100°C and, from 137 to 392 MPa. It is cleared that the creep strengths of RenéN5 and CMSX-4 are exceeded RenéN4 in all testing conditions. In addition, the rupture life of CMSX-4 at higher temperature/lower stress condition in this study is longer than the reported life in published papers.
   All creep properties obtained from this study are added to the database, and are not only used for the turbine design but also for the virtual jet engine computer simulation program.