【摘要】：鋁-鎂-硅合金是一種可形變熱處理鋁合金,具有較高的強(qiáng)度與導(dǎo)電性能組合,被廣泛用作鋁合金架空導(dǎo)線。本文針對鋁-鎂-硅合金線桿連鑄連軋工藝過程中實(shí)現(xiàn)在線固溶處理難以控制的生產(chǎn)現(xiàn)狀,結(jié)合水平連鑄、連續(xù)擠壓工藝特點(diǎn),提出一種6201鋁合金導(dǎo)線制備新工藝,包括水平連鑄、連續(xù)擠壓、拉拔和人工時效。通過在Gleeble-3500熱模擬機(jī)上的熱壓縮變形實(shí)驗(yàn),研究了水平連鑄6201鋁合金金高溫壓縮變形行為,確定其較佳的熱加工參數(shù)范圍;同時,利用光學(xué)顯微鏡(OM)、掃描電子顯微鏡(SEM)、透射電子顯微鏡(TEM)、室溫拉伸試驗(yàn)、顯微硬度和導(dǎo)電性能測試等手段,對該工藝所制備的鋁合金力學(xué)性能和組織演變規(guī)律進(jìn)行了研究。主要結(jié)果如下:(1)水平連鑄6201鋁合金在變形溫度為350-500℃,應(yīng)變速率為0.01-10s-1壓縮變形時,其流變應(yīng)力隨著變形溫度升高或應(yīng)變速率減小而減小�？梢圆捎冒╖ener-Hollomon參數(shù)的Arrhenius雙曲正弦關(guān)系描述合金的流變應(yīng)力行為,其變形激活能Q=188.6k J/mol。(2)基于材料動態(tài)模型,建立了水平連鑄6201鋁合金的熱加工圖,其最優(yōu)熱加工參數(shù)范圍是:變形溫度420-480℃和應(yīng)變速率3.5-10s-1。(3)水平連鑄6201鋁合金橫截面、縱截面的組織在晶粒大小、晶粒形貌、晶體取向分布方面不同,連續(xù)擠壓改變了合金原始組織的晶體取向分布和細(xì)化晶粒。(4)水平連鑄-連續(xù)擠壓可有效地實(shí)現(xiàn)6201鋁合金中Mg2Si相的在線充分固溶處理。(5)采用該新工藝制備的6201鋁合金導(dǎo)線的抗拉強(qiáng)度、延伸率和電導(dǎo)率分別為334.7MPa、6.0%和55.7%IACS,其力學(xué)與導(dǎo)電性能均可達(dá)到或超過傳統(tǒng)工藝制備導(dǎo)線的性能。
[Abstract]:Al-Mg-Si alloy is a kind of thermomechanical alloy, which has high strength and conductivity, and is widely used as aluminum alloy overhead conductor. In this paper, according to the current production situation that the on-line solution treatment is difficult to control in the process of continuous casting and rolling of Al-MgO-Si alloy wire rod, a new process for preparing 6201 aluminum alloy conductor is put forward combining with the characteristics of horizontal continuous casting and continuous extrusion. Includes horizontal continuous casting, continuous extrusion, drawing and artificial aging. The hot compression deformation behavior of 6201 aluminum alloy in horizontal continuous casting at high temperature was studied by means of the hot compression deformation experiment on Gleeble-3500 thermal simulator, and the better range of hot working parameters was determined. The mechanical properties and microstructure evolution of aluminum alloy prepared by (OM), scanning electron microscope (OM), (SEM), transmission electron microscope (SEM), tensile test at room temperature, microhardness and electrical conductivity were studied. The main results are as follows: (1) when the deformation temperature is 350-500 鈩，

本文編號：2215295