本文選題：粉末冶金 + 鋁基復(fù)合材料��； 參考：《湖南大學(xué)》2015年碩士論文

【摘要】：顆粒增強(qiáng)鋁基復(fù)合材料具有高比剛度、高耐磨性、熱穩(wěn)定性等優(yōu)異的力學(xué)性能,制備工藝相對(duì)簡(jiǎn)單,技術(shù)成熟,在汽車、航天航空、電子等領(lǐng)域有非常重要的應(yīng)用。微米/納米顆�；祀s增強(qiáng)鋁基復(fù)合材料具有更優(yōu)異的綜合性能,是目前鋁基復(fù)合材料領(lǐng)域的重點(diǎn)研究方向之一。本文采用粉末冶金法制備微米/納米顆�；祀s增強(qiáng)鋁基復(fù)合材料,分析并優(yōu)化混合粉末壓制工藝、燒結(jié)工藝,在此基礎(chǔ)上,制備出Si C(微米級(jí))-Ti B2(納米級(jí))雙相混雜增強(qiáng)鋁基復(fù)合材料,并與單一Si C顆粒和Ti B2顆粒增強(qiáng)鋁基復(fù)合材料進(jìn)行性能對(duì)比研究分析,通過密度與硬度分析、拉伸試驗(yàn)、XRD與SEM等表征分析,對(duì)所制備的鋁基復(fù)合材料組織性能進(jìn)行了深入研究。冷壓成型時(shí)復(fù)合材料的致密度隨著冷壓壓力的增加而升高,冷壓壓力750MPa時(shí),5%Si Cp/Al-Si致密度可達(dá)到93.68%,進(jìn)一步提高壓制壓力,致密度無(wú)明顯增加。復(fù)合材料的孔隙率隨著燒結(jié)溫度的升高而減少,冷壓坯料在640℃燒結(jié)并保溫40min條件下獲得的鋁基復(fù)合材料致密度最高,可達(dá)到92%以上。對(duì)單一顆粒和混雜顆粒增強(qiáng)鋁基復(fù)合材料來說,隨著增強(qiáng)顆粒體積含量的增加,鋁基復(fù)合材料的硬度、拉伸強(qiáng)度等性能總體呈現(xiàn)上升趨勢(shì),Si C顆粒增強(qiáng)、Ti B2顆粒增強(qiáng)以及Si C-Ti B2混雜增強(qiáng)鋁基復(fù)合材料的最佳的增強(qiáng)顆粒體積含量分別為5%、1.5%、5%Si C-1.5%Ti B2。相對(duì)于Si C、Ti B2單相增強(qiáng)鋁基復(fù)合材料,Si C-Ti B2混雜增強(qiáng)鋁基復(fù)合材料的性能有一定程度的提高。5%Si C-1.5%Ti B2雙相混雜增強(qiáng)鋁基復(fù)合材料的維氏硬度為53.39,抗拉強(qiáng)度為158MPa。顆粒增強(qiáng)鋁基復(fù)合材料斷裂為混合斷裂機(jī)制,當(dāng)顆粒與界面的結(jié)合較好時(shí),顆粒增強(qiáng)鋁基復(fù)合材料的主要斷裂機(jī)制為基體的韌性斷裂、顆粒斷裂和顆粒與界面撕裂;當(dāng)顆粒與界面結(jié)合較差時(shí),主要的斷裂機(jī)制為基體的塑性斷裂以及增強(qiáng)顆粒從基體界面的脫離。
[Abstract]:Particle reinforced aluminum matrix composites have excellent mechanical properties such as high specific stiffness, high wear resistance and thermal stability. The preparation process is relatively simple and the technology is mature. It has very important applications in automotive, aerospace and electronic fields. Micron / nanocrystalline hybrid reinforced aluminum matrix composites have better comprehensive properties and are one of the key research directions in the field of aluminum matrix composites. In this paper, micron / nano-particle hybrid reinforced aluminum matrix composites were prepared by powder metallurgy method. The compaction process and sintering process of mixed powder were analyzed and optimized. Sic (micrometer scale) two-phase hybrid reinforced aluminum matrix composites were prepared and compared with single sic particles and TiB2 particle reinforced aluminum matrix composites. The density and hardness of the composites were analyzed by density and hardness analysis. The microstructure and properties of the aluminum matrix composites were studied by tensile test, SEM and so on. The density of composites increases with the increase of cold pressing pressure, and the density of 5Si Cp/Al-Si can reach 93.68 when cold pressing pressure 750MPa. The compaction pressure is further increased, but the density does not increase obviously. The porosity of the composites decreases with the increase of sintering temperature, and the density of aluminum matrix composites sintered at 640 鈩，

本文編號(hào)：1912505