Aluminum alloy plastic working material and production method therefor

Abstract

The present invention provides an aluminum alloy plastic working material which has a low Young's modulus, but has an excellent proof stress and a method for efficiently producing the same. The aluminum alloy plastic working material of the present invention comprises: 5.0 to 10.0 wt % of Ca, and the remainder aluminum and unavoidable impurities, a volume ratio of an Al 4 Ca phase, which is a dispersed phase, is 25% or more. The Al 4 Ca phase comprises a tetragonal Al 4 Ca phase and a monoclinic Al 4 Ca phase, and an intensity ratio (I 1 /I 2 ) of the highest diffraction peak (I 1 ) attributed to the tetragonal system to the highest diffraction peak (I 2 ) attributed to the monoclinic system, which are obtained by an X-ray diffraction measurement, is 1 or less.

1 . An aluminum alloy plastic working material, which comprises:
 5.0 to 10.0 wt % of Ca, and   the remainder aluminum and unavoidable impurities,   a volume ratio of an Al 4 Ca phase, which is a dispersed phase, is 25% or more,   the Al 4 Ca phase comprises a tetragonal Al 4 Ca phase and a monoclinic Al 4 Ca phase, and   an intensity ratio (I 1 /I 2 ) of the highest diffraction peak (I 1 ) attributed to the tetragonal system to the highest diffraction peak (I 2 ) attributed to the monoclinic system, which are obtained by an X-ray diffraction measurement, is 1 or less.   
     
     
         2 . The aluminum alloy plastic working material according to  claim 1 , further comprising at least one or more of Fe: 0.05 to 1.0 wt % and Ti: 0.005 to 0.05 wt %. 
     
     
         3 . The aluminum alloy plastic working material according to  claim 1 ,
 wherein an average crystal grain size of the Al 4 Ca phase is 1.5 μm or less.   
     
     
         4 . A method for producing an aluminum alloy plastic working material, comprising:
 a first step for obtaining a plastic workpiece of an aluminum alloy by subjecting an aluminum alloy ingot which contains 5.0 to 10.0 wt % of Ca with the remainder aluminum and inevitable impurities, and has a volume ratio of an Al 4 Ca phase which is a dispersed phase of 25% or more to a plastic processing, and   a second step for subjecting to a heat treatment in a temperature range of 100 to 300° C.   
     
     
         5 . The method for producing an aluminum alloy plastic working material according to  claim 4 , wherein aluminum alloy ingot contains at least one or more of Fe: 0.05 to 1.0 wt % and Ti: 0.005 to 0.05 wt %. 
     
     
         6 . The method for producing an aluminum alloy plastic working material according to  claim 4 , wherein, before the first step, the aluminum alloy ingot is not subjected to a heat treatment where the ingot is maintained at a temperature of 400° C. or more. 
     
     
         7 . The aluminum alloy plastic working material according to  claim 2 , wherein an average crystal grain size of the Al 4 Ca phase is 1.5 μm or less.