热处理温度对铝钢复合板界面组织和性能的影响

Effect of heat treatment temperature on interfacial microstructures and bonding properties of Al-steel clad plate

作为船舶钢质主船体和铝质上层建筑的过渡连接件,铝钢复合板的性能将直接影响船舶建造的质量。采用SEM、XRD和硬度测试等方法,研究了热处理温度对Al-Al-Steel爆炸复合板的铝钢界面微观形貌、物相组成及硬度的影响。通过拉脱和剪切试验,得到了不同热处理温度下界面结合强度的变化规律。结果表明,随着热处理温度从315升高到550℃,纯铝层金属的硬度从47HV降低到21HV,发生明显的软化;当热处理温度达到450℃时,在界面处形成了一层呈连续分布的Fe-Al金属间化合物,新形成的化合物类型为Fe2Al5和FeAl3;并且FeAl金属间化合物的厚度随着温度的升高而增加。在上述因素的共同作用下,最终导致铝钢界面的结合强度随着热处理温度的升高而不断降低,其中Fe-Al金属间化合物的形成是强度降低的主要原因。

As a transitional joint between the steel of the main hull and the aluminum of superstructure,the performance of the aluminum-steel clad plate will directly affect construction quality of the ship.The effect of heat treatment temperature on interfacial microstructures and properties of explosively-welded Al-steel clad plate were investigated by SEM and XRD,and the vickers hardness was measured.The bonding properties were acquired through peel and shear tests.The results show that with the heat treatment temperature increasing from 315 to 550℃,the hardness of pure Al decreases from 47 HV to 21 HV,showing an obvious softening behaviour;when the temperature reaches 450℃,a continuous layer of Fe-Al intermetallic compound(IMC)is newly formed on the Al-steel interface and the types of the newly formed Fe-Al IMC are Fe2Al5 and FeAl3;and the thickness of Fe-Al IMC layer increases with heat treatment temperature.Under the combined effect of above factors,the bonding strength of the interface is continuously decreased with heat treatment temperature,where the influence of Fe-Al IMC accounts for the main reason.