添加铁元素对Cu-10Al-4Ni粉末冶金合金组织和性能的影响

Effect of Iron Addition on Microstructure and Properties of Cu-10Al-4Ni Powder Metallurgy Alloy

以铜粉、铝粉、镍粉和铜包铁粉为原料,采用粉末冶金工艺制备含不同质量分数(0,1.6%,3.2%,4.8%,6.4%)铁元素的Cu-10Al-4Ni合金,研究了铁含量对合金显微组织和性能的影响。结果表明:未添加铁元素的合金组织由κ_(Ⅲ)相、α相和Al_(4)Cu_(9)相组成;当添加质量分数1.6%的铁元素后,合金中的κⅢ相增多,Al_(4)Cu_(9)相减少;当铁元素质量分数达到3.2%时,Al_(4)Cu_(9)相进一步减少,合金中析出κ_(Ⅰ)相和κ_(Ⅱ)相;随着铁含量继续增加,Al_(4)Cu_(9)相消失,κ_(Ⅰ)相增多,而κ_(Ⅲ)相开始减少。随着铁含量的增加,合金的烧结密度减小,硬度先降低后增加再降低,当铁质量分数达到3.2%时硬度最大;合金的屈服强度随铁含量增加呈波动变化,当铁质量分数达到4.8%时屈服强度最大。

With copper powder,aluminum powder,nickel powder and copper-coated iron powder as raw materials,Cu-10Al-4Ni alloys containing different mass fractions(0,1.6%,3.2%,4.8%,6.4%)of iron were prepared by powder metallurgy process.The effect of iron content on the microstructure and properties of the alloy was studied.The results show that the microstructure of the alloy without iron addition consisted ofκ_(Ⅲ)phase,αphase and Al_(4)Cu_(9)phase.When the mass fraction of iron was 1.6%,theκ_(Ⅲ)phase increased and Al_(4)Cu_(9)phase decreased in the alloy.When the mass fraction of iron was 3.2%,Al_(4)Cu_(9)phase further decreased,andκ_(Ⅰ)andκ_(Ⅱ)phases were precipitated in the alloy.When the iron content continued to increase,the Al_(4)Cu_(9)phase disappeared,κ_(Ⅰ)phase increased whileκ_(Ⅲ)phase decreased.With increasing iron content,the sintered density of the alloy decreased,the hardness decreased first then increased and then decreased,and reached the maximum with iron mass fraction of 3.2%.The yield strength of the alloy fluctuated with increasing iron content,and reached the maximum when the mass fraction of iron was 4.8%.