本文關(guān)鍵詞： W-Y_2O_3復(fù)合材料 W-TiC-Y_2O_3復(fù)合材料 濕化學(xué)法 熱機(jī)械法 放電等離子燒結(jié) 氦離子輻照 熱負(fù)荷行為　出處：《合肥工業(yè)大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：鎢因為具有高熔點、熱導(dǎo)性好、高溫強(qiáng)度下能保持較高的強(qiáng)度等優(yōu)點,成為最具發(fā)展前景的面向等離子體第一壁候選材料。但鎢存在低溫脆性、再結(jié)晶脆性、輻照脆化和輻照損傷等問題,通過向鎢中添加第二相粒子,如Y_2O_3和TiC可以增強(qiáng)鎢基材料高溫和室溫力學(xué)性能和抗輻照性能。本文首先選擇濕化學(xué)法結(jié)合SPS制備了W-4vol%Y_2O_3復(fù)合材料,探究了粉末的最佳還原工藝,并研究了W-4vol%Y_2O_3塊體材料的燒結(jié)性能及抗熱沖擊、氦輻照性能。然后采用濕化學(xué)法制備了W-(4/8/12)vol%TiC-4vol%Y_2O_3系復(fù)合材料,探究了TiC含量對W-TiC-Y_2O_3復(fù)合材料顯微組織和性能影響。最后,提出熱機(jī)械法制備鎢基復(fù)合材料新工藝,并將熱機(jī)械法制備的W-12vol%TiC-4vol%Y_2O_3復(fù)合材料與濕化學(xué)法進(jìn)行抗熱沖擊和氘滯留性能對比。主要研究結(jié)果如下:(1)采用濕化學(xué)法制備W-4vol%Y_2O_3復(fù)合材料時,當(dāng)還原溫度為800℃、時間為1h時,前驅(qū)體粉末最佳的還原氫氣流速為600ml/min,其粒度最小,約200nm左右,且均勻性最好。(2)制備的W-4vol%Y_2O_3復(fù)合材料進(jìn)行不同能量熱沖擊試驗,隨著激光束熱通量增加,材料表面的鎢及Y_2O_3被熔化,材料內(nèi)部發(fā)生再結(jié)晶并產(chǎn)生裂紋。氦輻照后,基體表面生成納米級絮狀絨毛,Y_2O_3表面僅粗糙化,表現(xiàn)出更好的抗輻照性。(3)采用濕化學(xué)法在添加Y_2O_3基礎(chǔ)上,向鎢中添加TiC,發(fā)現(xiàn)隨著TiC含量的增加,W-TiC-Y_2O_3材料的致密度和硬度增加,晶粒逐漸細(xì)化,其中W-12vol%TiC-4vol%Y_2O_3復(fù)合材料晶粒最小,約5μm,且其第二相既分布在晶界,也分布在晶內(nèi)。(4)采用熱機(jī)械法制備的W-12vol%Ti C-4vol%Y_2O_3復(fù)合材料與濕化學(xué)法相比,致密度和硬度較高,晶粒更細(xì)小,材料強(qiáng)度更高。分析微觀成分,材料內(nèi)部生成氧化物Y_2(Ti_2O_7)和固溶體(W,Ti)C_(1-x)。分析兩種工藝制備的復(fù)合材料激光熱沖擊后的形貌以及輻照后的氘滯留數(shù)據(jù),結(jié)果表明熱機(jī)械法制備的W-TiC-Y_2O_3復(fù)合材料具有更好的抗熱沖擊和抗輻照性能。
[Abstract]:Because of the advantages of high melting point, good thermal conductivity and high strength at high temperature, tungsten is the most promising candidate material for plasma first wall, but tungsten has low temperature brittleness and recrystallization brittleness. The problems of irradiation embrittlement and radiation damage were studied by adding the second phase particles to the tungsten. For example, Yak _ 2O _ 3 and TiC can enhance the mechanical properties and radiation resistance of tungsten based materials at high temperature and room temperature. In this paper, W-4volo _ 3 / Y _ 2O _ 3 composites were prepared by wet chemical method combined with SPS. . The optimum process of powder reduction was studied, and the sintering properties and thermal shock resistance of W-4vol-Ys _ 2O _ 3 bulk material were studied. Radiation properties of helium. W-Li / 4 / 8 / 12 TiC-4volr / Ys / 22O3 composite materials were then prepared by wet chemical method. The effect of TiC content on the microstructure and properties of W-TiC-Y _ W _ 2O _ 3 composite was investigated. Finally, a new technology of preparing tungsten matrix composites by thermo-mechanical method was proposed. The thermal shock resistance and deuterium retention of W-12volum TiC-4vol3 composite prepared by thermomechanical method were compared with those of wet chemical method. The main results are as follows: 1). W-4volr / Y _ 2O _ 3 composite was prepared by wet chemical method. When the reduction temperature is 800 鈩，

本文編號：1442303