本文關(guān)鍵詞： 熱壓 靶材 孔徑 氧化鋅鋁 煅燒　出處：《粉末冶金技術(shù)》2017年06期 　論文類型：期刊論文

【摘要】：以ZnO和Al_2O_3粉體為原料,按照98∶2(質(zhì)量比)球磨混合制備氧化鋅鋁(aluminum zinc oxide,AZO)粉體,通過掃描電鏡和透射電鏡觀察粉體形貌及均勻性,確立最佳混合工藝;將混合均勻的粉體進行煅燒預(yù)處理后進行熱壓燒結(jié)致密化試驗,通過差熱法分析原料性能,阿基米德法分析靶材密度以及壓汞實驗分析氣孔演化對AZO靶材燒結(jié)致密化的影響。結(jié)果表明:微納米粉體在球磨4 hr時Al元素分布均勻性最好,煅燒前的混合粉體在差熱分析過程中失重0.43%并伴隨放熱效應(yīng);煅燒處理后粉體形貌類球形,在差熱分析實驗0℃-1000℃無失重,表明揮發(fā)組分排除干凈且無異常放熱效應(yīng),燒結(jié)性能得到優(yōu)化。采用預(yù)處理的AZO粉體在不同熱壓溫度和保溫時間下制備AZO靶材,分析熱壓致密過程中平均孔徑和閉孔率的變化規(guī)律。由此發(fā)現(xiàn):在熱壓致密化初級階段(溫度900℃~1100℃時),連通氣孔發(fā)生合并與生長,平均孔徑先稍有收縮隨后迅速增大為158 nm,同時閉孔率維持在0.5%以下,靶材密度不斷上升;當溫度升高至1150℃時,連通孔徑逐漸縮小至108 nm,大量連通氣孔轉(zhuǎn)為閉合狀態(tài)導(dǎo)致閉孔率迅速上升至7.2%以上,表明體系已經(jīng)進入到熱壓深度致密化階段。在1150℃、18 MPa下,保溫時間延長到70 min時,連通氣孔合并生長同時閉孔率異常增加至7%,孔徑分布范圍變寬導(dǎo)致出現(xiàn)反致密化現(xiàn)象;當保溫保壓時間延長至90 min時,氣孔尺寸減小到136 nm,閉孔率下降至3.7%,靶材相對密度上升到96.2%,在較低壓力和較短保溫時間下實現(xiàn)了AZO靶材的深度致密化。
[Abstract]:Zinc oxide aluminum zinc oxideAZO powder was prepared from ZnO and Al_2O_3 powder by ball milling with mass ratio of 98: 2. The morphology and homogeneity of the powder were observed by scanning electron microscope and transmission electron microscope, and the optimum mixing process was established. After calcining and pretreating the mixed powder, the densification test of hot pressing sintering was carried out, and the properties of raw materials were analyzed by differential calorimetry (DTA). The effects of pore evolution on the sintering densification of AZO targets were analyzed by Archimedean method and mercury injection experiments. The results showed that the distribution of Al elements was the best when the powder was milled for 4 hr. The weight loss of the mixed powder before calcination was 0.43% with exothermic effect during DTA, and the powder morphology was spherical after calcination, and there was no weight loss at 0 鈩，

本文編號：1526410