本文選題：鈦合金 + Ti-Al合金化層��； 參考：《材料工程》2017年02期

【摘要】：為提高鈦合金TC4的抗高溫氧化性能,采用激光表面合金化技術在鈦合金表面制備不同Nb摻雜量的Ti-Al合金化層。采用X射線衍射儀(XRD)、掃描電子顯微鏡(SEM)、能譜儀(EDS)、箱式電阻爐等對合金化層的組織結構和高溫氧化行為進行分析測試。結果表明,合金化層主要組成物相為TiAl以及少量的Ti_3Al相。Nb主要以置換溶質原子的形式固溶于合金化層中。合金化層組織均勻,與基體呈典型的冶金結合,在不含Nb的Ti-Al合金化層中發(fā)現(xiàn)大量的表層裂紋及少量的貫穿性裂紋,而在Nb摻雜的合金化層中未發(fā)現(xiàn)明顯的宏觀裂紋。合金化層在800℃保溫1000h的氧化增重顯著低于基體,表現(xiàn)出優(yōu)異的抗高溫氧化性能。相比而言,隨著Al含量和Nb摻雜量的提高,合金化層的抗高溫氧化能力也隨之提高。Nb摻雜提高Ti-Al合金化層抗高溫氧化性能的作用機理包括減少TiO_2中的空位缺陷、細化氧化物顆粒及促進Al_2O_3的形成。
[Abstract]:In order to improve the oxidation resistance of titanium alloy TC4 at high temperature, different NB doped Ti-Al alloying layers were prepared on the surface of titanium alloy by laser surface alloying technique. The microstructure and high temperature oxidation behavior of alloying layer were analyzed and measured by X-ray diffractometer, scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and box resistance furnace. The results show that the main composition of alloying layer is TiAl and a small amount of Ti_3Al phase. NB is mainly dissolved in the alloying layer in the form of substitution solute atoms. The microstructure of alloying layer is uniform, and it has typical metallurgical bonding with the matrix. A large number of surface cracks and a few penetrating cracks are found in the Ti-Al alloying layer without NB, but no obvious macroscopic cracks are found in the NB doped alloying layer. The oxidation weight gain of the alloying layer at 800 鈩，

本文編號：1801136