The effect of pure La and mischmetal(RE) on underside shrinkage of ZA27 alloy with cooling rate of 32 min-1 was investigated. The results show that the volumes of the underside shrinkage and the total shrinkage(unders...The effect of pure La and mischmetal(RE) on underside shrinkage of ZA27 alloy with cooling rate of 32 min-1 was investigated. The results show that the volumes of the underside shrinkage and the total shrinkage(underside shrinkage plus internal shrinkage) of the alloy decrease as the content of La or RE increases. When the contents of La and RE exceed 03%04%(mass fraction) respectively, the underside shrinkage is eliminated and the internal shrinkage moves upwards gradually. The mechanism that the underside shrinkage is eliminated is the falling of La and RE compounds and their accumulation on the bottom of the ZA27 alloy sample. Since La and RE can not effectively prevent phases(Al base solid solution) in the alloy from rising, the internal shrinkage is still close to the bottom of the ZA27 sample.展开更多
A genetic neural net work m odel about design of Mg content in the alloy , based on tested databetw een Mg and tensile intensity or elongation in Zn 27 % Al alloy , has been established . Theresult has sho w n th...A genetic neural net work m odel about design of Mg content in the alloy , based on tested databetw een Mg and tensile intensity or elongation in Zn 27 % Al alloy , has been established . Theresult has sho w n that the genetic neural netw ork is a better an d m ore applied method for m a terials design than the regress analysis .展开更多
文摘The effect of pure La and mischmetal(RE) on underside shrinkage of ZA27 alloy with cooling rate of 32 min-1 was investigated. The results show that the volumes of the underside shrinkage and the total shrinkage(underside shrinkage plus internal shrinkage) of the alloy decrease as the content of La or RE increases. When the contents of La and RE exceed 03%04%(mass fraction) respectively, the underside shrinkage is eliminated and the internal shrinkage moves upwards gradually. The mechanism that the underside shrinkage is eliminated is the falling of La and RE compounds and their accumulation on the bottom of the ZA27 alloy sample. Since La and RE can not effectively prevent phases(Al base solid solution) in the alloy from rising, the internal shrinkage is still close to the bottom of the ZA27 sample.
文摘A genetic neural net work m odel about design of Mg content in the alloy , based on tested databetw een Mg and tensile intensity or elongation in Zn 27 % Al alloy , has been established . Theresult has sho w n that the genetic neural netw ork is a better an d m ore applied method for m a terials design than the regress analysis .
