A　study　on　the　precipitation　hardening　and　recrystallization　behavior　of　dilute　Al-Er-Hf　and　Al-Er-Hf-Zr　alloys　has　been　carried　out.　The　results　show　that　both　Al-0.045Er-0.18Hf　and　Al-0.045Er-0.08Zr-0.1Hf　alloys　can　obtain　remarkable　age　strengthening　effect　and　recrystallization　resistance.　The　precipitation　hardening　rate　of　Al-0.045Er-0.08Zr-0.T1　Hf　is　accelerated　compared　with　that　of　the　Al-0.045Er-0.18Hf　alloy　due　to　substituting　0.08　at%　Zr　for　Hf,　which　can　be　ascribed　to　the　sequential　precipitation　of　solute　elements　on　the　basis　of　the　disparity　in　their　intrinsic　diffusivities　(D-Er　＞　D-Zr　＞　D-Hf).　The　peak　hardness　values　for　the　Al-0.045Er-0.08Zr-0.1Hf　are　644　MPa　and　662　MPa　after　isochronal　aging　to　450　degrees　C　and　isothermal　aging　at　350　degrees　C　for　84　h,　respectively,　which　are　higher　than　those　of　the　Al-0.045Er-0.18Hf　alloy.　The　recrystallization　temperature　of　Al-Er-Hf-Zr　alloy　is　450　degrees　C,　about　25　degrees　C　higher　than　that　of　the　Al-Er-Hf　alloy　due　to　the　larger　f/r　ratio　of　precipitates　in　Al-Er-Hf-Zr　alloys.　(C)　2015　Elsevier　B.V.　All　rights　reserved,