研究了块体Zr₅₅Al₁₀Ni₅Cu₃₀非晶合金在脉冲激光重熔下的组织演化行为。激光熔凝区始终保持非晶结构,热影响区(HAZ)在激光能量密度大或者扫描速度慢时晶化倾向大,扫描速度≥15 mm/s时可避免晶化,但发生结构弛豫过程。热影响区非晶部分晶化时,晶化为内部具有层状共生生长结构的球状晶粒,晶化尺度为微米级,晶化相由四方相Zr2Cu及面心立方相Zr2Ni组成。熔池底部位置的热影响区较熔池靠近表面边缘晶化严重。熔池底部热影响区的晶粒尺寸随远离熔凝区逐渐变小,且晶粒内部的层数在热影响区呈现靠近熔凝区侧多于靠近基材侧的趋势。

The microstructure evolution of bulk metallic glass Zr₅₅Al₁₀Ni₅Cu₃₀ during pulsed laser remelting is investigated. It is found that the remelted zone always keeps amorphous structure and the crystallization tendency in heat-affected zone (HAZ) increases with the laser energy density increasing or the scanning velocity decreasing. The crystallization in the HAZ can be avoided but the structural relaxation occurres when the scanning velocity is equal to or greater than 15 mm/s. When the crystallization occurres in the HAZ,the micron-scale spherical grain is formed in the pattern of the multi-layer with the inner coupled lamellar structure,and crystalline phases are composed of tetragonal Zr2Cu and face-centered cubic Zr2Ni. Crystallization in the HAZ near the bottom of molten pool is more severe than that in the region near edge of surface. The grain size in the HAZ near bottom of molten pool decreases away from the remelted zone,and the layer numbers of the spherical grain in the HAZ near the remelted zone are more than that near the substrate side.