(華南理工大學(xué) 國家金屬材料近凈成形工程技術(shù)研究中心，廣州 510640)
摘 要: 鑒于塊狀非晶合金(BAAs)的低塑性特征，回顧了利用放電等離子燒結(jié)−非晶晶化法制備高性能塊狀材料的成形技術(shù)，即先機(jī)械合金化制備鈦基多組元非晶合金粉末，然后利用放電等離子燒結(jié)在粉末的過冷液相區(qū)固結(jié)非晶粉末，再利用非晶晶化法使燒結(jié)的非晶塊體在隨后的燒結(jié)和熱處理過程中晶化析出β-Ti延性相，控制延性相的形貌、尺度和分布，合成以非晶相或β-Ti晶化相為基體的鈦基塊狀非晶復(fù)合材料(CBBAAs)，研究不同添加或替換組元對TiNbCuNiAl非晶粉末顆粒尺寸、熱物性和微觀結(jié)構(gòu)的作用，探索了不同燒結(jié)參數(shù)對合成的CBBAAs微觀結(jié)構(gòu)和力學(xué)性能的影響規(guī)律，揭示合成含晶化相CBBAAs的理論基礎(chǔ)和非晶晶化過程中晶粒形核長大的規(guī)律，提出并利用“發(fā)展的軟硬模型”來闡釋應(yīng)力作用下CBBAAs的斷裂機(jī)理。研究結(jié)果提供一種極具前途的粉末冶金復(fù)合材料制備方法，該方法能制備尺寸較大、力學(xué)性能優(yōu)異的含晶化相的塊狀復(fù)合材料。
關(guān)鍵字: 塊狀非晶合金；納米晶材料；超細(xì)晶材料；復(fù)合材料；放電等離子燒結(jié)；機(jī)械合金化；晶化；微觀結(jié)構(gòu)；力學(xué)性能
（National Engineering Research Center of Near-net-shape Forming for Metallic Materials,
South China University of Technology, Guangzhou 510640, China）
Abstract:In order to circumvent low plasticity of bulk amorphous alloys (BAAs), a material forming method by coupling spark plasma sintering with crystallization of amorphous phase, fabricating composites based on BAAs (CBBAAs) with excellent mechanical property was reviewed systematically. By appropriate annealing of sintered BAAs prepared from spark plasma sintering in the supercooled liquid region of a mechanically alloyed amorphous powder, crystallized ductile β-Ti phase with controllable grain size, phase morphology and distribution can precipitate from the amorphous phase, and therefore, CBBAAs with a matrix of amorphous phase or crystallized β-Ti phase were obtained. The effect of different additions or substitute elements on the particle size, thermal property and microstructure of TiNbCuNiAl amorphous powder, and the influence of different sintering parameters on the microstructure and mechanical property of fabricated CBBAAs were investigated. The theoretical bases of fabricating crystallized phase-containing CBBAAs, and nucleation and growth mechanism of crystalline phase during the crystallization process were elucidated. The facture mechanism of fabricated CBBAAs under stress was explained based on a proposed “Developed hard-soft model”. The results provide a promising method for fabricating large-sized crystallized phase-containing bulk composites with excellent mechanical property by powder metallurgy.
Key words: bulk amorphous alloy; nanocrystalline materials; ultrafine-grained materials; composites; spark plasma sintering; mechanical alloying; crystallization; microstructure; mechanical property
