基體合金時(shí)效行為的影響
(1.四川大學(xué) 制造科學(xué)與工程學(xué)院，成都 610065；
2.四川大學(xué) 金屬材料工程系，成都 610065)
摘 要: 用擠壓鑄造方法制備了Mullite/Al-Cu-Si復(fù)合材料。用硬度(HB)測(cè)試儀、差示掃描量熱儀(DSC)和顯微鏡研究含Si量變化和Mullite纖維對(duì)Al-Cu-Si合金時(shí)效硬化行為的影響；元素Si、Mullite纖維以及二者同時(shí)存在對(duì)Al-Cu-Si合金時(shí)效析出序列的影響。結(jié)果表明：Si和Mullite纖維明顯抑制了Al-Cu合金GP區(qū)的形成；隨著含Si量增加，Al-Cu-Si合金的時(shí)效硬化過(guò)程加快；Mullite纖維對(duì)Al-Cu和Al-Cu-Si合金的時(shí)效硬化過(guò)程都具有加速作用，同時(shí)提高了基體合金的時(shí)效硬度，但相對(duì)而言，Mullite纖維對(duì)無(wú)Si的Al-Cu合金的時(shí)效硬化加速作用更為明顯一些。
關(guān)鍵字: Mullite纖維；Si；Al-Cu-Si合金；時(shí)效硬化
behaviours of Mullite/Al-Cu-Si
composite and its base alloy
GAO Sheng-ji2，TU Ming-jing2
（1.School of Manufacturing Science and Engineering，
Sichuan University,Chengdu 610065，China；
2.Department of Metallic Materials Engineering，
Sichuan University，Chengdu 610065，China）
Abstract:Short Mullite fibre reinforced Al-4.0Cu-Si composites and their monolithic alloys with different Si content (0%，2%，5%，7%) we re fabri cated by squeeze casting.The effects of Si content and short Mullite fibre on the age-hardening behaviours of composites and the effects of Si，Mullite fibre and both of them on the precipitation procedure have be en investigated by means of hardness(HB) measurement device，differential scanning calorimeter (DSC) and optical micrograph.It is shown that GP zone formation is heavily suppressed by either Si or Mullite fibre. With the increasing of Si content，the age-hardening response of Al-Cu-Si ternary alloys is accelerated.The acceleration of ageing is observed both in Mullite fibre reinforced Al-Cu composite and in mullite fibre reinforced Al-Cu-Si composite and the aged hardness of the testing composites is largely increased.Relatively speaking，the acceleration effect of mullite fibre in silicon free (no addition of silicon) AlCu based compos ite is greater than that in silicon containing Al-Cu-Si based composites.
Key words: Mullite fibre; Si; Al-Cu-Si alloy; ageing
