(北京工業(yè)大學材料與制造學部，北京 100124)
摘 要: 本文采用傳統(tǒng)鑄錠冶金的方法制備不同Si和Er含量的Al-Zr合金，研究Si和Er對Al-Zr合金時效析出行為的影響。結果表明：Si的添加促進了Al-Zr合金的時效硬化響應，Si大大降低第二相Al3Zr的析出溫度。Al-0.25Zr-0.30Si合金在325 ℃等溫時效時獲得最佳時效強化增量，最高硬度值達到57.1HV，較其固溶態(tài)合金增加25.8 HV。Al-Zr合金獲得最佳時效硬化增量的Si含量為0.30%(質量分數(shù))。Er的添加進一步促進Al-Zr合金的時效響應，拓寬了Al-Zr合金時效析出溫度范圍(325~375 ℃)，析出相變得更加細密。Al-0.25Zr-0.30Si-0.25Er合金在350 ℃等溫時效時獲得最大時效強化增量，最高硬度值達到60.5 HV，這主要是由于Si、Er復合微合金化比單獨添加Si更能提高Al-Zr合金沉淀相的數(shù)量密度并細化其尺寸。
關鍵字: Al-Zr合金；析出相；時效強化；微合金化
（Faculty of Materials and Manufacturing, Beijing University of
Technology, Beijing 100124, China）
Abstract:The effect of Si and Er on the aging behavior of Al-Zr alloy was studied. The results show that the Si-addition promotes the aging strengthening effect of Al-Zr alloy, and greatly reduces the precipitation temperature of Al3Zr precipitates. The Al-0.25Zr-0.30Si alloy obtains the maximum increment of strengthening when isothermal aging at 325 ℃. The highest hardness is 57.1 HV, which is greater by 25.8 HV than that in the solid solution state. Content of 0.30% Si is optimal to obtain the maximum hardening increment for Al-0.25Zr alloy. The addition of Er further promotes the aging response of Al-Zr alloy, which widens the aging precipitation temperature range (325-375 ℃) of Al-Zr alloy and the precipitates become finer and denser. Al-0.25Zr-0.30Si-0.25Er alloy has the maximum hardening increment as isothermal aging at 350 ℃ and the peak hardness is 60.5 HV. Because co-microalloying with Er and Si can increase the number density and refine the size of precipitates in Al-0.25Zr alloy compared with adding Si alone.
Key words: Al-Zr alloys; precipitates; aging strengthening; microalloying
