(中南大學(xué) 粉末冶金國家重點(diǎn)實(shí)驗(yàn)室，長沙 410083)
摘 要: 采用等離子噴涂技術(shù)成功在坯體密度為1.8 g/cm3 炭/炭復(fù)合材料上面制備厚度為1.2 mm與基體結(jié)合良好的較致密的W涂層的試樣。利用氧乙炔焰分別測(cè)試其在30 s、60 s、90 s和120 s下的燒蝕性能。結(jié)果表明:試樣的質(zhì)量燒蝕率和線燒蝕率均隨時(shí)間的增加而增加。其中，最大質(zhì)量燒蝕率和線燒蝕率分別為7.8 μg/s和3.5 μm/s。XRD、SEM分析表明:在燒蝕中心區(qū)，涂層試樣的燒蝕以升華分解為主，同時(shí)，還伴有氧化燒蝕和微區(qū)機(jī)械剝蝕；在燒蝕過渡區(qū)，涂層的燒蝕機(jī)制以熱氧化和燃?xì)鉀_刷為主；而在燒蝕邊緣區(qū)，涂層的燒蝕則主要表現(xiàn)為弱氧化燒蝕。
關(guān)鍵字: 大氣等離子噴涂；耐燒蝕；W涂層；炭/炭復(fù)合材料
（State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:Compact tungsten coatings with thickness of 1.2 mm were successfully deposited by the atmosphere plasma spraying technique on carbon/carbon composites with the density of about 1.8 g/cm3. W coating ablation resistances were studied by using oxyacetylene flame for 30 s, 60 s, 90 s and 120 s. The results show that both the mass ablation rate and linear ablation rate increase with the ablation time prolonging. The maximum mass ablation rate and linear ablation rate are 7.8 μg/s and 3.5 μm/s, respectively. The phase compositions and microstructures of the composites before and after ablation were examined by XRD and SEM. In the ablation center, the ablation mechanism of the coated sample is sublimation and decomposition, combined with thermo-oxidation and mechanical denudation. In the transitional field, the ablation mechanism of the coating is controlled by thermo-oxidation and scouring. And in the ablation rim, the coating exhibits slight oxidation behavior.
Key words: air plasma spray; ablation resistance; W coating; carbon/carbon composite
