(哈爾濱理工大學(xué) 材料科學(xué)與工程學(xué)院，哈爾濱 150040)
摘 要: 采用固相合成方法制備Al2O3亞微米顆粒增強(qiáng)AZ31鎂基復(fù)合材料，利用OM、SEM、TEM對(duì)Al2O3/AZ31鎂基復(fù)合材料進(jìn)行組織觀(guān)察，利用維氏硬度儀、電子萬(wàn)能拉伸試驗(yàn)機(jī)對(duì)Al2O3/AZ31鎂基復(fù)合材料進(jìn)行力學(xué)性能測(cè)試。結(jié)果表明：經(jīng)過(guò)固相合成后，Al2O3亞微米顆粒均勻的分布在AZ31基體中，通過(guò)對(duì)基體位錯(cuò)運(yùn)動(dòng)的釘扎作用，使該區(qū)域的位錯(cuò)密度增加，促進(jìn)動(dòng)態(tài)再結(jié)晶形核，復(fù)合材料的晶粒被顯著細(xì)化。Al2O3/AZ31復(fù)合材料的力學(xué)性能隨著Al2O3亞微米顆粒含量的增加而提高，當(dāng)Al2O3顆粒含量為2%時(shí)，復(fù)合材料的力學(xué)性能達(dá)到最大值，其硬度、抗拉強(qiáng)度、屈服強(qiáng)度和伸長(zhǎng)率分別為83HV、302 MPa、203 MPa和8.15%。
關(guān)鍵字: 固相合成；AZ31鎂基復(fù)合材料；力學(xué)性能；強(qiáng)化機(jī)理；顯微組織
（School of Materials Science and Engineering, Harbin University of Science and Technology, Harbin 150040, China）
Abstract:The solid-phase synthesis was used to prepare the submicron size Al2O3/AZ31 composite. Its microstructure and mechanical properties were characterized by optical microscopy, scanning electron microscopy, transmission electron microscopy, Vickers hardness tester and electron universal strength tester. The results show that the submicron size Al2O3 particles are uniformly distributed in AZ31 magnesium matrix after solid-phase synthesis. Al2O3 particles increase the dislocation density by pinning the dislocation motion of the matrix, promoting the dynamic recrystallization nucleation, resulting in refined grains of the composites. Meanwhile, the mechanical properties of the composites increase with the increase of the content of submicron size Al2O3 particles. When the content of Al2O3 particles is 2%, the mechanical properties of the composite reach the maximum. The hardness, tensile strength, yield strength and elongation are 83HV, 302 MPa, 203 MPa and 8.15%, respectively.
Key words: solid-phase synthesis; AZ31 magnesium composites; mechanical property; strengthening mechanism; microstructures
