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研究了不同形态Zr_(55)Al_(10)Ni_5Cu_(30)非晶合金(块体和粉末)在不同升温和冷却条件下的晶化行为.发现Zr_(55)Al_(10)-Ni_5Cu_(30)在不同热历史下的晶化行为有较大差别.对于块体非晶合金,在常规热处理条件下,合金的升温和冷却速率较低,Zr_(55)Al_(10)Ni_5Cu_(30)块体非晶合金在初始晶化温度Tx以上开始晶化,形成CuZr_2纳米晶.随着热处理温度的升高,晶粒尺寸增大,当热处理最终温度超过熔点后,合金在随炉冷却过程中形成了粗大的CuZr_2板条+板条间(CuZr_2)+(Zr,Cu,Al,Ni)共晶组织;在激光熔凝条件下,合金的升温和冷却速率较高,Zr_(55)Al_(10)Ni_5Cu_(30)块体非晶合金随单点熔凝次数的增加,晶化效应逐渐累加,热影响区中逐渐出现微米级球晶的弥散析出,并长大,随后失稳形成沿熔池边界带状分布,尺寸可达几百微米的等轴晶.对于粉末非晶合金,由于Zr_(55)Al_(10)Ni_5Cu_(30)非晶粉末的冷却强度不如块体非晶,冷却速率较块体低,造成粉末颗粒在激光熔凝过程中晶化为微米级的等轴枝晶,并随着激光能量的升高,等轴枝晶尺寸增大.
The crystallization behavior of Zr55V10 Ni_5Cu_30 amorphous alloys (bulk and powder) under different heating and cooling conditions was investigated. It was found that Zr55V10-5Nu5Cu30 ) Crystallization behavior under different thermal history is quite different.For the bulk amorphous alloy, under normal heat treatment conditions, the rate of heating and cooling of the alloy is low, and the Zr 55 Al 10 Ni 5 Cu 30 The bulk amorphous alloys begin to crystallize above the initial crystallization temperature Tx to form CuZr 2 nanocrystals. As the heat treatment temperature increases, the grain size increases. When the final heat treatment temperature exceeds the melting point, the alloy forms during the furnace cooling (CuZr_2) + (Zr, Cu, Al, Ni) eutectic microstructure of coarse CuZr_2 slab + The crystallization of Ni_5Cu_ (30) bulk amorphous alloy gradually increases with the increase of single-point melting, and the microscopic spherulites gradually appear in the heat-affected zone and grow up, and then destabilize along the weld pool The equiaxed grains with a size of hundreds of micrometers are distributed in the boundary.For the powder amorphous alloys, the cooling strength of amorphous Zr_ (55) Al_ (10) Ni_5Cu_ (30) powders is not good Bulk amorphous, the cooling rate lower than the block body, causing the powder particles through the laser remelting into micron Cheng Zhongjing equiaxed dendrite, and with increasing the laser energy, increase in the size of equiaxed dendrite.