(重慶大學(xué) 材料科學(xué)與工程學(xué)院，重慶 400044)
摘 要: 采用通管滴落法研究1758 K溫度下Ti-Al系合金熔體與TiN的潤濕行為，結(jié)果表明：當Al的質(zhì)量分數(shù)為40%、50%、60%、70%和80%時，初始接觸角分別為68°、92°、106°、140°和140°，初始接觸角對合金成分依賴較大。當Al含量較高時，Al會氧化生成Al2O3膜包裹在液滴表面，影響初始接觸角的測量，但平衡接觸角對合金成分依賴較小，均小于20°，且隨Al含量的增加略微減小。由于潤濕后試樣的界面上富集了大量的Ti和少量的Al而沒有明顯的化學(xué)反應(yīng)產(chǎn)物存在，且通過計算可知合金中Ti的化學(xué)勢明顯高于基板中Ti的化學(xué)勢，因此，在化學(xué)勢差的作用下Ti向界面吸附，促進體系的潤濕。此外，當Al含量大于60%時，在鋪展的末期Al會顯著揮發(fā)，但其對平衡接觸角的影響較小。在實驗中，XRD檢測到的AlN和TiAl3是由于合金與基板接觸及N擴散后與合金反應(yīng)生成，但其生成量很少。
關(guān)鍵字: Ti-Al合金；潤濕；氧化；吸附；蒸發(fā)
（School of Material Science and Engineering, Chongqing University, Chongqing 400044, China）
Abstract:The wetting behavior of TiN by Ti-Al alloys was studied using an improved sessile drop method at 1758 K. When the mass fractions of aluminum in the alloys are 40%, 50%, 60%, 70% and 80%, the initial contact angle are 68°, 92°, 106°, 140° and 140°, respectively, the initial contact angle has a large dependent on the composition of alloys. When aluminum content is higher than 70%, it could be oxidized to Al2O3 film covering the surface of drop. However, the finial equilibrium contact angles are all less than 20°, which slightly decrease with increasing the aluminum content. The interface after wetting is enriched in high content of titanium and low content of aluminum, no reactant is found. Through calculation, it is known that the chemical potential of titanium in alloys is higher than that in TiN. Under this condition, the titanium is adsorbed on the interface which improves the wetting undoubtedly. In addition, when content of aluminum is higher than 60%, Al will evaporate largely during the final period of spreading, but it has little effect on the variation of contact angle. The AlN and TiAl3 detected by XRD are due to the slightly reaction between alloys and TiN, but the contents are low.
Key words: Ti-Al alloy; wetting; oxidation; adsorption; evaporation
