连铸大圆坯包晶反应区域影响因素分析

Analysis on Influencing Factors of Peritectic Reaction Region of Continuous Casting Round Billet

通过理论计算和生产实践分析了合金元素和冷却速度对包晶反应的影响,结果表明:Si、Mn、S使包晶点左移,P、Al使包晶点右移,在圆管坯成分范围内,P、Si、Al影响较小,Mn、S影响较大;连铸冷却使包晶反应点向左移动,圆管坯冷却条件下,冷速使包晶点移动0.03%。实际生产中,C含量应避免0.08%～0.11%区间,避开包晶反应强烈区,同时选择恰当的结晶器保护渣,能够减少裂纹缺陷的发生。

Peritectic reaction is an important reaction in low carbon steel continuous casting,then surface longitudinal cracks are closely related to uneven growth of initial solidified shell.The effect of alloying element and cooling rate on peritectic reaction is studied by theoretical arithmetic and experiment research in this paper.The results show that Si,Mn and S make the peritectic point move to left,P,Al make the peritectic point move to right.The degree of Mn,S are stronger while P,Si and Al are weaker.Cooling rate make the peritectic point move left 0.03%under the condition of round billet continuous casting.Composition adjustment to avoid region of intense peritectic reaction and choosing appropriate casting powder can effectively reduce the occurrence of cracks in practical production.