累积叠轧对原位ZrB_2/6082Al复合材料组织和力学性能的影响

Effects of Accumulative Roll-bonding Processing on Microstructure and Mechanical Properties of in Situ ZrB_2/6082Al Composites

基于6082Al-K_2ZrF_6-KBF_4体系,通过熔体直接反应法制备原位纳米3wt%ZrB_2/6082Al复合材料,并在300℃下对其进行累积叠轧(ARB),获得了纳米相均匀分布的高性能铝基复合材料。OM、XRD、SEM和TEM分析表明,纳米增强体团簇被打碎,并随着道次的增加分布越来越均匀;其中析出相,比如Fe-Mn-Si相,也随着道次的增加逐渐被打碎并细化;复合材料的晶粒同时被极大地细化,经过9道次ARB,晶粒平均尺寸达到380 nm。拉伸试验表明,复合材料抗拉强度随着道次增加逐渐增大,最大为310 MPa,伸长率为15.8%,与6082Al基体相比,分别提高了138.5%和66.3%。

Based on 6082Al-K2Zr F6-KBF4 system, the in situ nano 3wt%ZrB2/6082Al composites were prepared by direct melt reaction method. And the accumulative roll-bonding （ARB） at 300 ℃ was carried out. High performance aluminum matrix composites with uniform distribution of nano-phase were obtained. OM, XRD, SEM and TEM analysis show that, nano reinforced clusters are broken, and the distribution is more and more uniform with the increase of the pass; and the precipitates of the alloy, such as the Fe-Mn-Si phases can also be broken and refined with the increase of the rolling pass; the grain size of the composite is greatly refined, and the average grain size of the composite is 380 nm after 9 passes ARB. Tensile tests show that the tensile strength of the composite increases with the increase of the pass, the maximum is 310 MPa, and the elongation is 15.8%, which is improved by 138.5% and 66.3% respectively, compared with the 6082Al matrix.