Abstract: The effect of Ca-Si and FeS adding order in Ca-treatment process and Ca/S ratio for steel on morphology  and  quality  of sulphide  in  0.048%～0.065%  S medium-carbon  steel(0.46～0.57C,0.83～0.94Mn,0.21～0.24Cr,  0.03~0.04Mo)has been studied by a carbon tube fumnace in laboratory.the results showed that the length and quantity of sulphide in steel by treatment first adding FeS then adding Ca-Si were obviously lower than that first adding Ca-Si then adding FeS;and with increasing Ca/S ratio in steel, the quantity of spherical multi-phase inclusions increased while the quantity of strip-shapc MnS decreased,of which the size increased. The available Ca/S ratio for steel by compound treatment using Ca-Si is ～0.03.

Key words:  , Medium-Carbon Structure Steel,Ca-Treatment,Sulphide

摘要： 在实验室用碳管炉研究了含0.048%0.065%硫的中碳钢(%:0.46~0.57C,0.83~0.94Mn,0.21~0.24Cr,0.03~0.04Mo)钙处理时,加入Ca-Si和FeS先后顺序以及钢中Ca/S值对该钢硫化物形态和数量的影响。结果表明,先加FeS后加Ca-Si处理时,钢中硫化物的长度与数量均较先加Ca-Si后加FeS处理时有明显降低。随钢中Ca/S值增加,钢中颗粒状复合夹杂物的数量增加,同时长条状的塑性硫化物夹杂数量减少,但尺寸增大。采用Ca-Si复合处理时,钢中合理的Ca/S值约为0.03。

关键词: 中碳结构钢, 钙处理, 硫化物