喷涂粉末对Al-Cu-Fe准晶涂层组织结构的影响

准晶材料具有低热导率、低磨擦系数、良好的耐磨性和抗氧化性、高硬度、高温塑性等优异性能,使之适于作为表面防护涂层.为了提高钛合金的抗高温氧化性能和耐磨性能, 采用低压等离子喷涂方法LPPS (Low Pressure Plasma Spraying)在钛合金表面制备了Al-Cu-Fe准晶涂层.通过改变喷涂粉末的成分和粒度大小,研究了喷涂粉末对制备态涂层相结构及微观形貌的影响. 由X-射线衍射XRD(X-Ray Diffraction)、扫描电镜SEM(Scanning Electronic Microscope)分析得出:采用原子比为Al70Cu20Fe10、粒度为-325目的粉末制备的涂层,在800℃下真空退火处理2?h后,结构均匀致密,二十面体准晶相(I相)含量高,并只含有少量的β相.

Effects of spraying powder composition and particle size on microstructures of Al-Cu-Fe quasicrystalline coatings

Quasicrystals have been widely applied for surface protection coating because of their distinguished properties including low thermal conductivity and coefficient of friction, remarkable oxidation and wear resistances, and high hardness etc. To improve the high temperature oxidation and wear resistance of titanium alloy, the Al-Cu-Fe quasicrystalline coatings were produced on titanium alloy substrates using LPPS (low pressure plasma spraying) method. The effect of the spraying powders on the phase structure and microstructure of as-sprayed coatings was studied by altering the composition and the size of spraying powders. The results of XRD (X-ray diffraction), SEM(scanning electronic microscope)show that the Al-Cu-Fe quasicrystalline coating is dense and uniform, by preparing from Al70Cu20Fe10 powders with particle size of –325 mesh(<44.5μm). After annealing under vacuum condition of 800℃ for 2 hours, it is observed that the icosahedron phase is the major phase together with a few β- Al (Cu, Fe) phase.