块体非晶合金Zr_(45) Cu_(48)Al_7激光焊接过程中晶化行为的研究

Study of crystallization in laser welding of Zr_(45) Cu_(48)Al_7 bulk metallic glass

非晶合金作为一种异于晶态合金的金属材料,其受焊行为与晶态材料突出的区别在于非晶材料的晶化问题。采用了激光焊接技术连接块体非晶合金Zr45Cu48Al7,研究了焊接过程中焊缝和热影响区的晶化行为。基于DSC实验结果,推导了块体非晶合金Zr45Cu48Al7晶化转变温度与加热速率立方根的正比关系,并将此结果应用于激光焊接加热过程中,进行了热影响区(HAZ)晶化体积的研究,分析了焊缝凝固后没有形成枝状晶的原因。

As the bulk metallic glasses are much different from crystallized alloys,the main difference between them during welding process is crystallization process.In this paper,the laser welding is used to joint Zr45Cu48Al7(at%) bulk metallic glass.The crystallization process in the seam and heat affected zone(HAZ) are analyzed in this paper during the welding process.Based on the differential scanning calorimeter(DSC) technology,the linear relationship of the crystallized temperature in the mode of continuous heating and the cube root of the heating speed was deduced,which was used to study the value of crystallized volume in HAZ during heating process and to analyze the reason of no dendrite existed.