2O3，Y2O3）與鎢粉混合，隨后通過冷等靜壓、中頻感應(yīng)燒結(jié)、旋鍛、拉拔等一系列工藝制備了W-1.5La2O3-0.1Y2O3-0.1ZrO2（質(zhì)量分?jǐn)?shù)，%）材料。對含有納米和微米尺寸稀土氧化物的陰極樣品使用相同的焊接電流，分別進(jìn)行了0.5、1、2 h的氬弧焊。結(jié)果表明，具有納米級稀土氧化物的樣品在焊接過程中表現(xiàn)出更高的工作穩(wěn)定性，燒損同比降低了近85.4%。此外，隨著工作時間的延長，陰極尖端不同區(qū)域的稀土氧化物聚集度顯著增加。結(jié)合COMSOL Multiphysics溫度模擬發(fā)現(xiàn)，第二相的擴(kuò)散活化能降低了近34%。這是因為更為細(xì)小的第二相有效地控制了鎢基體組織的演變，保留了大量晶界作為通道，促進(jìn)了活性物質(zhì)在電子發(fā)射過程中的擴(kuò)散。;Nanometer-(70?80 nm) and micrometer-sized (500?600 nm) rare-earth (RE) oxides (La2O3, Y203) were separately mixed with tungsten powder by a mechanical alloying method. Afterwards, the W-1.5La2O3-0.1Y2O3-0.1ZrO2 (wt%) was prepared by cold isostatic pressing, medium-frequency induction sintering, rotary forging, and drawing. Then we performed tungsten argon arc welding (TIG) under the same welding current for 0.5, 1, and 2 h on the cathode samples containing, separately, nanometer- and micrometer-sized RE oxides. Results show that the sample with nanometer-sized RE oxides exhibits higher working stability during the welding process, and the burning loss is decreased by nearly 85.4%. Moreover, with prolonging the working time, the aggregation degree of RE oxides in different regions of the tip significantly increases. Combined with the temperature simulation by COMSOL Multiphysics, we found that the diffusion activation energy of the second phase is decreased by nearly 34%. This is because the finer second phase effectively controls the evolution of the tungsten matrix structure, thus preserving many grain boundaries as channels and promoting the diffusion of active substances."/>
2O3-Y2O3-ZrO2;鎢陰極;氬弧焊;稀土氧化物;納米級;微米級;COMSOL Multiphysics;W-La2O3-Y2O3-ZrO2;tungsten cathode;TIG;rare-earth oxides;nanometer-sized;micrometer-sized;COMSOL Multiphysics"/>