In-situ Synthesis of TiAl Matrix Composites by Combustion Process.

一种燃烧反应综合症和自我传播高温综合症（SHS）使用元素粉末中的化学反应已经被利用来准备陶瓷和金属金属。最近，许多注意事项都集中在陶瓷矩阵和金属矩阵复合物的合成上，这一过程的平均值。本研究的目标是评估用燃烧反应过程制备的Ti 2ALC或TiB 2轻质和高温材料的Ti 2ALC复合材料的微观结构和性能，根据燃烧反应过程制备的复合材料，遵循电弧熔化或HIP反应介质。该复合材料由来自钛、Al和C粉末混合物形成，具有两个相位的基质γ+α2（lamellar structure）、强化粒子Ti 2AlC和一些多孔性。Subsequent Arc Melting保留了基质和强化，而在Porosity中有显著的减少。作为一种铸造制剂，强化Ti 2AlC颗粒均匀分布在基质TiAl （~ 30μm）中。 ... More 颗粒形状类似于长度为5-15微米的大小，估计其总体比率约为5-10。同时，这种层状结构在同一物种中并不被观察。Instead，小粒子大小为0.5μm，直径为可见。该复合物的两种环境和升高温度的强度明显地增加了Ti 2ALC对环境温度约800兆帕和1173 K约400兆帕的差异，对此表示赞赏。此外，这些复合材料在弯曲测试中具有0.9%的可变性。Furthermore， fracture toughness value 14.0 MPam D21/2 D2被用于同源化的特定，在另一方面，γ和α2颗粒被激发而没有小的TiB 2颗粒大于1微米分布在矩阵中，如HIP-Al-B powders产生的。However，一个具有新的预先配置的TiB 2颗粒周围的颗粒边界在全质TiAl/TiB 2复合体矩阵中是可见的。Those composites possessed bending strength of 700 MPa， bending strain of 0/3% and fracture toughness of 15 MpamイD11/2イエD1， respectively。Less（低）

A combustion reaction synthesis and self-propagating high-temperature synthesis (SHS) using the chemical reaction among elemental powders has been utilized for preparing ceramics and intermetallics. Recently, many attentions are focusing on synthesizing of ceramic matrix and intermetallic matrix composites by mean of this process. The aims of this study is to evaluate microstructures and properties of TiAl matrix composites reinforced with Ti2ALC or TiB2 for light-weight and high-temperature material prepared by the combustion reaction process, following arc melting or HIP reactive sintering.The composite formed by the combustion reaciton from Ti, Al, C powder mixture had a matrix of two phase γ+α2 (lamellar structure), reinforcement particulate Ti2AlC, and some porosity. Subsequent arc melting retained the matrix and reinforcement as before with significant reduction in porosity. In as cast specimens, reinforcement Ti2AlC particles are uniformly distributed in the matrix TiAl (〜30μm). … More The particles are rod-like in shape with sizes 5-15μm in length, and the aspect ratio is estimated to be about 5-10. While, such lamellar structure is not observed in the homogenized specimens. Instead, smaller particles with sizes of 0.5μm in diameter are visible. The strength of the composite both ambient and elevated temperatures clearly increased by the dispersion of reinforcement of Ti2AlC to about 800MPa at ambient temperature and about 400MPa at 1173K, respectively. Also, these composites have 0.9% ductility in bending test. Furthermore, fracture toughness value 14.0MPamィイD21/2ィエD2 is obtained for homogenized specimens.On the other hand, dual structure consisting of γand α2 grains were excited and small TiB2 particles less than 1μm were distributed in the matrix of as HIPed specimens produced from Ti-Al-B powders. However, duplex structure with newly precipitated TiB2 particles around the grain boundaries were occasionally visible in the matrix of homogenized TiAl/TiB2 composites. Those composites possessed bending strength of 700MPa, bending strain of 0/3% and fracture toughness of 15 MpamィイD11/2ィエD1, respectively. Less