针对 6101 铝合金半连续铸造易产生热裂纹的问题，通过 SEM 等手段对裂纹试样进行分析表征，明确裂纹起源及扩展机制。 结果表明，6101 铝合金扁锭热裂纹为纵向裂纹，裂纹起源于 V、Cr、Mn、Ti 等杂质形成的硼化夹杂物团聚，这些硼化物来自硼化处理后残留的硼化物夹杂，以及残留在熔体中的杂质元素与 Al-5Ti-B 细化剂反应形成的新硼化物，在浇注过程中流入到结晶器随铸锭凝固。 结合 ProCAST 数值模拟铸锭半连续铸造过程中的应力场分布，发现铸锭心部与表面温度梯度大、凝壳厚度减小及局部应力集中，导致铸锭从富含夹杂物的区域开裂并形成纵向裂纹。 在此基础上，提出延长硼化处理后静置时间的优化措施，以去除大尺寸团聚夹杂物，降低热裂倾向，同时满足高导电性要求。

This study focuses on the issue of hot tearing that is easily encountered during the semi-continuous casting of 6101 aluminium alloys. Flat ingots with hot tearing were characterized using SEM and other analytical techniques to clarify the origin and propagation mechanisms of hot tearing. The results reveal that the hot tearing in the 6101 aluminium alloy manifests as longitudinal cracks, which initiate from the agglomeration of boride inclusions formed by impurities such as V, Cr, Mn, and Ti. These borides originate both from residual boride inclusions after the boron treatment process and from newly formed borides resulting from reactions between impurities remaining in the melt and the Al-5Ti-1B grain refiner, which are transported into the mold during casting and subsequently solidified within the ingot. Combined with ProCAST numerical simulations of stress distribution during semi-continuous casting, significant temperature gradients between the ingot core and surface, reduced solidified shell thickness, and localized stress concentration lead to crack initiation in regions rich in inclusions, thereby promoting the formation of longitudinal cracks. On the basis of these findings, an optimized measure is proposed: prolonging the holding time after boron treatment to eliminate large agglomerated inclusions, reduce the susceptibility to hot tearing, and simultaneously meet the requirements for high electrical conductivity.