The　isochronal　and　isothermal　crystallization　behaviors　of　Zr　70Al12.5Fe17.5　and　Zr75Al　7.5Fe17.5　glassy　alloys　were　studied　using　differential　scanning　calorimeter　(DSC).　Under　isochronal　heating,　the　two　amorphous　alloys　possessed　different　primary　phases　in　the　initial　crystallization.　The　activation　energies　for　the　glass　transition　and　crystallization　of　Zr　75Al7.5Fe17.5　glassy　alloy　determined　by　the　Kissinger,　Ozawa　and　Augis-Bennett　plots　were　larger　than　those　of　Zr　70Al12.5Fe17.5　alloy.　Isothermal　kinetics　of　glassy　alloys　was　modeled　by　the　Johnson-Mehl-Avrami　equation.　For　the　Zr　70Al12.5Fe17.5　glassy　alloy,　the　Avrami　exponents　were　mostly　in　the　range　from　2.48　to　2.68,　which　indicated　a　constant　nucleation　rate　and　a　diffusion-controlled　three-dimensional　growth.　The　Zr75Al7.5Fe17.5　glassy　alloy　exhibited　relatively　larger　Avrami　exponents　of　between　2.72　and　3.07,　implying　a　diffusion-controlled　three-dimensional　growth　with　increasing　nucleation　rate.　©　2014　Elsevier　B.V.