通过对比两组夹杂物含量及尺寸分布不同的高碳含铜TWIP钢的拉伸性能及其断口形貌, 分析了非金属夹杂物对该钢拉伸性能的影响。结果表明: 在拉伸过程中, 钢中的非金属夹杂物成为孔洞的形核点, 并导致孔洞提前萌生, 但该钢易发生孪生和高加工硬化率的特点, 延缓了显微孔洞的形核和长大, 再加之其无颈缩的塑性断裂形式, 使得其拉伸性能对非金属夹杂物在一个较大范围内具有高度容忍性; 当该钢中夹杂物的面积分数由0.171%增加到0.394 94%, 等效圆直径大于5 μm夹杂物的面密度由4个·mm-2增加到29个· mm-2时, 其抗拉强度、断后伸长率等拉伸性能仅降低了1%～3%, 仍表现出优异的拉伸性能。

The tensile properties of high carbon copper-bearing TWIP steel with different contents of non-metallic inclusions and distribution of size were compared to study the effect of non-metallic inclusions on tensile properties. The results show that non-metallic inclusions in the TWIP steel became the nucleation points of cavities under tensile load, leading to the early initiation of cavities. But the nucleation and growth of cavities were delayed because the TWIP steel was easy to form twinning and had high strain hardening rate. Besides, as a result of plastic fracture without necking, the tensile properties of the steel had a high level of tolerance for non-metallic inclusions. While the area fraction of the non-metallic inclusions in the TWIP steel raised from 0.171% to 0.394% and the surface density of the inclusions in equivalent diameter above 5 μm improved from 4 to 29, the various tensile properties such as tensile strength and elongation only reduced by 1% to 3%, showing good tensile properties.