【摘要】：利用OM、SEM、TEM和電子萬能試驗機研究Y元素的含量對3種Mg-Y-Zn合金的顯微組織和室溫及高溫力學(xué)性能的影響。結(jié)果表明,擠壓態(tài)Mg_(97)Y_2Zn_1和Mg_(96)Y_3Zn_1合金主要由α-Mg基體、沿擠壓方向排列的帶狀18R-LPSO相和α-Mg內(nèi)的層片狀14H-LPSO相組成,而Y含量最高的Mg_(95)Y_4Zn_1合金中還形成Mg_(24)Y_5相顆粒。室溫時,隨Y含量的增加,合金的抗拉強度逐漸升高,塑性不斷下降;隨溫度的升高,3種合金的抗拉強度均下降,但塑性顯著提升。由于合金中起強化作用的LPSO相和Mg_(24)Y_5相熱穩(wěn)定性好,合金在高溫時仍保持優(yōu)異的力學(xué)性能,其中Mg_(95)Y_4Zn_1合金在300℃時的抗拉強度為252 MPa,伸長率達到27.1%�？傮w來看,Mg_(96)Y_3Zn_1合金具有最佳的綜合力學(xué)性能。
[Abstract]:The effect of Y content on the microstructure, mechanical properties at room temperature and high temperature of three Mg-Y-Zn alloys was studied by OM,SEM,TEM and electronic universal testing machine. The results show that the extruded Mg_ (97) Y_2Zn_1 and Mg_ (96) Y_3Zn_1 alloys are mainly composed of 偽 -Mg matrix, banded 18R-LPSO phase arranged along the extrusion direction and lamellar 14H-LPSO phase in 偽 -Mg, while Mg_ (24) Y _ (5) phase particles are also formed in Mg_ (95) Y_4Zn_1 alloy with the highest Y content. At room temperature, the tensile strength of the alloy increases with the increase of Y content, and the plasticity decreases, and the tensile strength of the three alloys decreases with the increase of temperature, but the plasticity increases significantly. Because of the good thermal stability of LPSO phase and Mg_ (24) Y _ 5 phase in the alloy, the alloy still has excellent mechanical properties at high temperature. The tensile strength of Mg_ _ (95) Y_4Zn_1 alloy at 300 鈩，

本文編號：2249568