$Al_3M$(M=Ti,V,Zr) intermetallic compound was modified by substituting transition elements in order to design a dispersion phase having high coarsening resistance in Al alloys for high temperature application. Three intermetallic compound dispersed Alloys made with a high volume percent of $Al_3$(Ti,V,Zr) are prepared by vacuum arc melting. Two intermetallic phases are found in alloys. One is V rich $D0_22-Al_3$(Ti,V,Zr) and the other is Zr rich $D0_23-Al_3$(Ti,V,Zr). Their compositional and morphological studies were made along with the lattice mismatches between the matrix and intermetallics, and the lattice misfit between two different $Al_3M$ phases is found to decrease conspicuously with increase in Ti content, and this phenomenon were maintained in which only intermetallic compound were existed. To be used as the basis for alloy design, this study has been continued on constructing the ternary section of $Al_3Ti-Al_3V-Al_3Zr$ system in quaternary Al-Ti-V-Zr phase diagram. The addition of Mn to the tetragonal $Al_3(Ti_{1-x}Zr_x)$ phase produces the cubic $L1_2$-type $Al_66Mn_9(Ti,Zr)_25$ with small amount of second phases such as $Al_8Mn_5$ and $Al_2Zr$ still existing in the as-cast state. Second phases disappear when intermetallic compounds are homogenized at 1000℃ for 24 hour, and alloys are monolithic with compositional segregations still existent. So, the combined addition of Ti and Zr makes the alloy more brittle compared to the addition of Ti or Zr alone. The tetragonal $D0_23$ intermetallic compound were produced from the pseudo ternary $Al_3Ti-Al_3V-Al_3Zr$ diagram, and the Mn added cubic $L1_2$-type $Al_66Mn_9(Ti_{1-x}Zr_x)_25$ were produced. This intermetallic compound were produced in the form of powder and mixed with pure Al by attritor mill and then vacuum hot pressed. IDS (intermetallic-dispersion strengthened) Al Alloys prepared in this way were analyzed in terms of phase stabilities and microstructures. The intermetallic dispersant in IDS alloy were less than 1 ㎛ after vacuum hot pressed and were not coarsened at 425℃ for 400 hours. And the microhardness of each alloys was not changed. The compression test were performed at room temperature and 420℃ that was 0.75 melting point of Al. The yield stress of $D0_23$ and $L1_2$ intermetallic dispersed alloy at room temperature were showed 920 and 800 Mpa, and at 420℃ were showed 260 and 187 Mpa respectively.
