本文關(guān)鍵詞： 超細銅粉 真空 蒸發(fā)冷凝 制備　出處：《昆明理工大學(xué)》2011年碩士論文　論文類型：學(xué)位論文

【摘要】：超細銅粉由于具有一系列與常規(guī)材料不同的物理、化學(xué)特性,被廣泛用于粉末冶金、催化、醫(yī)藥等領(lǐng)域,隨著社會經(jīng)濟的發(fā)展和科學(xué)技術(shù)的進步,對超細銅粉的數(shù)量和質(zhì)量的要求越來越高。本研究在分析各種超細銅粉的制備方法及工藝、銅粉制備設(shè)備的研究基礎(chǔ)上,提出了真空蒸發(fā)冷凝制備超細銅粉的新思路。通過激光粒度分析儀(LS)、掃描電鏡(SEM)、透射電鏡(TEM)、X射線衍射儀(XRD)、輝光放電質(zhì)譜儀(GDMS)、差示掃描量熱分析儀(DSC)等手段對超細銅粉粒度、形貌、物相、純度、熔點進行表征,所獲得超細球形銅粉平均粒徑小于2μm,超細片狀銅粉平均粒徑為10-30μm、厚1～2μm,粒徑分布較窄且均勻可控,分散性好,純度高。 本研究自行設(shè)計了兩類新型冷凝器來收集超細銅粉,一類是三層石墨冷凝器,另一類是水冷鋼板。論文考察了兩類冷凝器的主要影響因素,探討了真空蒸發(fā)冷凝制備超細銅粉的機理,系統(tǒng)研究了工藝參數(shù)對金屬銅的蒸發(fā)速率、超細銅粉的形貌、平均粒度、粒度分布、產(chǎn)率等的影響規(guī)律,得到如下結(jié)論： 1.金屬銅的蒸發(fā)速率和超細銅粉產(chǎn)率隨蒸發(fā)溫度(T)的升高、真空度(P)的增大、銅金屬熔體蒸發(fā)面積(S)的增大、坩堝內(nèi)銅液面高度(H)的增大而增大。 2.通過單因素條件試驗,分別得到了兩類冷凝器下的優(yōu)化工藝條件。研究發(fā)現(xiàn)蒸發(fā)溫度、真空度、保溫時間對超細銅粉的形貌、平均粒度和粒度分布有相似的影響,且為主要影響因素。隨蒸發(fā)溫度升高、真空度降低、保溫時間增大,超細銅粉的平均粒度增大,粒度分布變寬。對于三層石墨冷凝器,最佳工藝條件為：蒸發(fā)溫度為1673K,壓力為10Pa,保溫時間為70min,最佳冷凝區(qū)域為第二層；對于水冷鋼板,最佳工藝條件為：蒸發(fā)溫度為1673K,壓力為10Pa,保溫時間為70min,冷卻水流量為160L/h,冷凝高度為7cm。 3.在不同的工藝條件下所制備的超細銅粉的形貌差別很大。小顆粒銅粉一般呈現(xiàn)球形或類球形；大顆粒銅粉往往呈現(xiàn)表面平整的片狀。通過調(diào)節(jié)真空蒸發(fā)冷凝制備超細銅粉工藝參數(shù)可以控制超細銅粉的平均粒度、粒度分布和形貌。
[Abstract]:Ultrafine copper powder has been widely used in powder metallurgy, catalysis, medicine and other fields because of a series of physical and chemical properties different from conventional materials. With the development of social economy and science and technology, the ultrafine copper powder has been widely used in the fields of powder metallurgy, catalysis, medicine and so on. The requirement of quantity and quality of ultrafine copper powder is higher and higher. This research is based on the analysis of the preparation method and technology of various ultrafine copper powder and the research of copper powder preparation equipment. A new idea of preparing ultrafine copper powder by vacuum evaporation condensation was put forward. By means of laser particle size analyzer, scanning electron microscope (SEM), and transmission electron microscope (TEM), the X-ray diffractometer (XRD) was used. The particle size, morphology, phase, purity and melting point of ultrafine copper powder were characterized by GDMS and DSC. The average particle size of ultrafine spherical copper powder is less than 2 渭 m, the average particle size of ultrafine flake copper powder is 10-30 渭 m, the thickness of copper powder is 1 ~ 2 渭 m, the particle size distribution is narrow, uniform and controllable, the dispersion is good, and the purity is high. In this study, two new types of condensers were designed to collect ultrafine copper powder, one is three-layer graphite condenser and the other is water-cooled steel plate. The mechanism of preparing ultrafine copper powder by vacuum evaporation condensation was discussed. The influence of process parameters on the evaporation rate, morphology, average particle size, particle size distribution and yield of metal copper powder were systematically studied. The following conclusions have been drawn: 1. The evaporation rate of copper and the yield of ultrafine copper powder increase with the increase of evaporation temperature (T), the vacuum degree (P), and the evaporation area (S) of copper melt. The increase of copper surface height in crucible increases. 2. Two kinds of condensers were optimized by single factor experiments. The morphology of ultrafine copper powder was investigated by evaporation temperature, vacuum and holding time. With the increase of evaporation temperature, the vacuum degree decreases, the holding time increases, and the average particle size of ultrafine copper powder increases. For the three-layer graphite condenser, the optimum process conditions are as follows: evaporation temperature is 1673K, pressure is 10Pa, holding time is 70min, and the best condensing area is the second layer. For water-cooled steel plate, the optimum technological conditions are as follows: evaporation temperature is 1673K, pressure is 10Pa, holding time is 70min, cooling water flow rate is 160L / h, condensation height is 7cm. 3. The morphology of ultrafine copper powder prepared under different technological conditions is very different. The average particle size, particle size distribution and morphology of ultrafine copper powder can be controlled by adjusting the technological parameters of vacuum evaporation condensation to prepare ultrafine copper powder.
【學(xué)位授予單位】：昆明理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2011
【分類號】：TF123.23

【引證文獻】

相關(guān)碩士學(xué)位論文 前1條

1 楊先凱;銅砷銻多元合金真空蒸餾的研究[D];昆明理工大學(xué);2012年

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本文編號：1490734