【摘要】：自上世紀(jì)的80年代末,ECR離子源為核物理及重離子加速器等領(lǐng)域做出了突出的貢獻(xiàn),此后世界各地的科學(xué)家們紛紛開展了對ECR離子源的研究。ECR離子源得到不斷發(fā)展,其種類從早期的第一代離子源裝置演變到如今以超導(dǎo)離子源技術(shù)為代表的第三代裝置,其所能產(chǎn)生的離子類型也已從早期的幾種氣體如氮?dú)�、氧氣等的中低電荷態(tài)離子,到現(xiàn)在從H到U的所有金屬或非金屬原子的高電荷態(tài)離子。大部分金屬元素在自然界中處于固態(tài),需要將其氣態(tài)化才能進(jìn)入ECR離子源中產(chǎn)生對應(yīng)的元素離子,且氣態(tài)化的金屬原子(或簇團(tuán))數(shù)量需達(dá)到一定值。當(dāng)前,在ECR離子源中產(chǎn)生這些在常溫常壓下只以固態(tài)形式存在的元素氣態(tài)主要有以下幾種方法:爐子加熱法、直接等離子體加熱法、等離子體濺射法、激光熔融技術(shù)以及揮發(fā)性化合物金屬離子(MIVOC,Metallic ion from volatile compound)法等,其中爐子加熱法具有束流強(qiáng)度高、穩(wěn)定性好的特點(diǎn)。爐子加熱法按其工作溫區(qū)主要分為低溫爐、高溫爐,其中高溫爐主要針對熔點(diǎn)1500 ℃以上的金屬元素如鈷、鈦、釩、鉑、鈾等的強(qiáng)流離子束產(chǎn)生。本論文課題設(shè)計(jì)一種目標(biāo)工作在1800～2000 ℃的高溫金屬爐,通過ANSYS仿真模擬分析了直流加熱電阻爐中鉭坩堝的溫度分布及其在ECR離子源工作環(huán)境的強(qiáng)磁場中所受的洛倫茲力,并對坩堝高溫下所受熱應(yīng)力進(jìn)行模擬分析。根據(jù)模擬分析結(jié)果研制了直流加熱電阻爐的結(jié)構(gòu),并對其進(jìn)行了離線測試,實(shí)驗(yàn)中鉭坩堝在1800 ℃以上發(fā)生的形變與ANSYS模擬結(jié)果相符,根據(jù)模擬分析給出了改進(jìn)方案。改進(jìn)后的電阻式加熱高溫爐能在1500 ℃時穩(wěn)定維持48小時以上,而在1846 ℃時穩(wěn)定維持6小時以上。對直流加熱電阻爐進(jìn)行了在線測試,得到了 25 eμA的Ni19+以及185 eμA的Pb28+,驗(yàn)證所設(shè)計(jì)的高溫爐能在ECR離子源強(qiáng)磁場的環(huán)境中工作,同時針對出現(xiàn)的問題分析了影響高溫爐穩(wěn)定運(yùn)行的因素。與此同時,研制了高頻加熱感應(yīng)爐及電子束加熱蒸發(fā)爐,并對兩者進(jìn)行了離線測試,結(jié)果表明兩者均能使坩堝溫度達(dá)到1800℃以上。對電子束加熱蒸發(fā)爐進(jìn)行了在線測試,結(jié)果表明電子束加熱蒸發(fā)爐受ECR離子源弧腔內(nèi)強(qiáng)磁場洛倫茲力的作用而無法正常工作,有待改進(jìn)。
[Abstract]:Since the late 1980s, ECR ion sources have made outstanding contributions to nuclear physics and heavy ion accelerators. Since then, scientists all over the world have carried out research on ECR ion sources. ECR ion sources have been continuously developed. Its species evolved from the early generation ion source devices to the third generation devices represented by the superconducting ion source technology, and the ion types it can produce have also changed from the low charge state ions of several gases such as nitrogen and oxygen. The highly charged state ions of all metal or non-metallic atoms from H to U up to now. Most metal elements are in solid state in nature, and they need to be gaseous to enter the ECR ion source to produce corresponding element ions, and the number of gaseous metal atoms (or clusters) should reach a certain value. At present, there are several methods to produce the gaseous state of these elements in ECR ion source only in solid state at room temperature and atmospheric pressure: furnace heating, direct plasma heating, plasma sputtering, and so on. Laser melting technology and volatile compound metal ions (MIVOC,Metallic ion from volatile compound) method, the furnace heating method has the characteristics of high beam intensity and good stability. The furnace heating method is mainly divided into low temperature furnace and high temperature furnace according to its working temperature region. The high temperature furnace is mainly used to produce high current ion beam of metal elements such as cobalt, titanium, vanadium, platinum, uranium and so on, whose melting point is above 1500 鈩，

本文編號：2405566