摘要
混杂增强镁基复合材料将两种或多种不同性质的增强相同时加入到基体中,发挥了各种增强相与基体的优势,可得到综合性能良好的复合材料。研究了挤压铸造及铸挤一体化成形对0.5%Ti_(p)/AZXW9100(质量分数,下同)、0.5%TiB_(2p)/AZXW9100及0.5%Ti_(p)+0.5%TiB_(2p)/AZXW9100镁基复合材料微观组织、力学性能的影响规律。结果表明,单独添加0.5%Ti_(p)或0.5%TiB_(2p)均能细化复合材料的铸坯基体晶粒;联合添加0.5%Ti_(p)+0.5%TiB_(2p)后,铸坯基体晶粒细化效果最佳(118.25μm减小至53.79μm)。添加0.5%Ti_(p)后,复合材料的β-Mg_(17)Al_(12)相显著细化,第二相面积分数相对于基体合金减少,是3种材料中面积分数最低的;添加0.5%TiB_(2p)后,β-Mg_(17)Al_(12)相尺寸增大,第二相面积分数最大;联合添加0.5%Ti_(p)+0.5%TiB_(2p)后,β-Mg_(17)Al_(12)相相对于单独添加0.5%TiB_(2p)显著细化,第二相面积分数(5.175%)含量介于单独添加0.5%TiB_(2p)(5.694%)和0.5%Ti_(p)(3.642%)之间,但高于基体合金(4.433%)。单独添加Ti_(p)或TiB_(2p)均能减弱基体的织构强度,联合添加0.5%Ti_(p)+0.5%TiB_(2p)得到了最小的基体织构强度。添加0.5%TiB_(2p)能够提高复合材料强度但使伸长率下降;添加0.5%Ti_(p)小幅提高材料强度,同时显著提高伸长率;联合添加0.5%Ti_(p)+0.5%TiB_(2p)后,复合材料的屈服强度和抗拉强度分别为211和318 MPa,较基体分别提高13.4%和7.4%,且伸长率达到14.9%,兼具较高的强度和良好的韧性。
Hybrid reinforced magnesium matrix composites incorporate two or more reinforcement phases with different properties into the matrix,leveraging the advantages of each reinforcement phase and the matrix to achieve composites with excellent comprehensive performance.This study investigated the effects of squeeze casting and continuous squeeze casting-extrusion on the microstructure and mechanical properties of 0.5 wt.%Ti_(p)/AZXW9100,0.5 wt.%TiB_(2p)/AZXW9100,and 0.5 wt.%Ti_(p)+0.5 wt.%TiB_(2p)/AZXW9100 magnesium matrix composites.The results show that the addition of either 0.5 wt.%Ti_(p) or 0.5 wt.%TiB_(2p) alone can refine the as-cast matrix grains of the composites.The most significant grain refinement effect(from 118.25μm to 53.79μm)is achieved when 0.5 wt.%Ti_(p) and 0.5 wt.%TiB_(2p) are added together.With the addition of 0.5 wt.%Ti_(p),theβ-Mg_(17)Al_(12) phase in the composite is significantly refined,and the area fraction of the second phase decreases compared with that of the matrix alloy,becoming the lowest among the three materials.In contrast,the addition of 0.5 wt.%TiB_(2p) increases the size of theβ-Mg_(17)Al_(12) phase and results in the highest second-phase area fraction.When 0.5 wt.%Ti_(p) and 0.5 wt.%TiB_(2p) are added together,theβ-Mg_(17)Al_(12) phase is significantly refined compared with the addition of 0.5 wt.%TiB_(2p) alone,and the second-phase area fraction(5.175%)lies between that of the individual additions of 0.5 wt.%TiB_(2p)(5.694%)and 0.5 wt.%Ti_(p)(3.642%),although it remains higher than that of the matrix alloy(4.433%).The addition of Ti_(p) or TiB_(2p) alone weakens the texture strength of the matrix,whereas the combined addition of 0.5 wt.%Ti_(p)+0.5 wt.%TiB_(2p) results in the lowest matrix texture strength.The addition of 0.5 wt.%TiB_(2p) improves the strength of the composite but reduces its elongation.In contrast,the addition of 0.5 wt.%Ti_(p) slightly increases the strength but significantly improves the elongation.When 0.5 wt.%Ti_(p) and 0.5 wt.%TiB_(2p) are added together,the composite achieves a yield strength of 211 MPa and a tensile strength of 318 MPa,representing increases of 13.4%and 7.4%,respectively,compared with those of the matrix alloy,while maintaining an elongation of 14.9%.This demonstrates a combination of high strength and excellent toughness.
作者
郭光辉
郭文波
吕书林
向渴望
严兆祥
毛有武
吴树森
GUO Guanghui;GUO Wenbo;LYU Shulin;XIANG Kewang;YAN Zhaoxiang;MAO Youwu;WU Shusen(National Key Laboratory of Forming and Mold Technology,School of Materials Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)
出处
《铸造技术》
2025年第6期541-549,共9页
Foundry Technology
基金
国家自然科学基金(52175321)。
关键词
镁基复合材料
混杂增强
微观组织
力学性能
热挤压
铸挤一体化
magnesium matrix composites
hybrid reinforcement
microstructure
mechanical properties
hot extrusion
continuous squeeze casting-extrusion
