粉末冶金结合热轧制备高硼铝合金组织与性能研究

采用粉末冶金结合热轧成形工艺制备含硼质量分数为7%与12%的中子屏蔽用高硼铝合金（Al-7% B与Al-12% B），并对不同工艺条件下铝硼合金的组织与性能进行研究。结果表明:在机械球磨5 min+放电等离子烧结条件下，Al-7% B合金中AlB₂体积分数高于Al-12% B合金，且分布更加均匀。放电等离子烧结后进行热轧有利于提高试样的相对密度，减少硼粉团聚。在450℃固溶处理2 h，Al-7% B合金试样的拉伸强度和屈服强度达到峰值，分别为145.7 MPa和99.4 MPa。由10B面密度理论计算结果可知，厚度相近时，热轧后高硼铝合金10B面密度均可达到BoralTM水平。

Study on microstructures and properties of high boron aluminum alloy prepared by powder metallurgy combined with hot rolling

High boron aluminum alloys for neutron shielding (Al-7%B and Al-12%B alloys by mass) were fabricated by powder metallurgy combined with hot rolling. The microstructures and properties of high boron aluminum alloys were investigated in different process conditions. In the results, the volume fraction of AlB₂ particles in Al-7%B alloy compacts sintered by spark plasma sintering after ball milling for 5 min is higher than that of Al-12%B alloy, and the distribution of AlB₂ particles shows more uniformly in Al-7%B alloy compacts. The hot rolling after spark plasma sintering is beneficial to increase the relative densities of compacts and decrease the agglomerations of boron powder in samples. The tensile and yield strengths of Al-7%B alloy quenched at 450℃ for 2 h reach 145.7 MPa and 99.4 MPa, respectively. According to the theoretical calculations, the areal densities of the hot rolled aluminum boron alloys reach the level of BoralTM.