模铸线材表面增碳的产生原因和对策

线材表面增碳严重影响最终产品性能，选取6024等钢种作为研究对象，重点分析模铸钢坯表面的增碳原因，通过对钢锭模内部质量、浇铸保护渣、浇铸速度和热处理工艺等因素与增碳效果进行对比试验，并根据试验结果确定相应改善钢坯表面增碳措施。结果表明，浇钢过程中使用的保护渣含碳量为18％左右成为钢锭表面增碳的主要来源，因此，采用无碳保护渣是减少钢坯或盘条表面增碳的可行方法。

Reasons for and measures against surface recarburization of mould cast wire rod

The performance of wire rod is significantly influnced by surface recarburization. This paper investigated steels of different grades such as 6024, and analyzed the reasons for surface recarburization of mould cast billets. Experiments were performed to study the effects of mould cast ingot quality, casting powder, casting speed and heat treatment on surface recarburization. Improvement measures were determined based on the experiments. The results show that casting powder with a carbon content of about 18% is the main carbon source for surface recarburization. Therefore, the most effective method of reducing surface recarburization of billets and wire rod is to use carbon-free casting powder.