高碳铬铁合金固相显微结构及破碎性能

Solid phase microstructure and crushing properties of high carbon ferrochrome alloy

为了研究高碳铬铁合金在浇注过程添加硅铁粉和铝后固相显微结构及破碎性能变化,在0.2t多功能炼钢中试炉重熔某铁合金公司生产的高碳铬铁,浇注时分别添加硅铁粉和铝,分析重熔的常规高碳铬铁、添加铝及硅铁粉的高碳铬铁的固相显微结构,并将样品经颚式破碎机破碎。结果表明,高碳铬铁显微结构主要由(Cr,Fe)7C3固态相和(Cr,Fe)7Si固态相组成,有部分TiN、MnS和Al2O3夹杂物析出,常规高碳铬铁中未发现Al2O3夹杂物,而添加硅铁粉和铝的高碳铬铁中均析出了Al2O3及TiN夹杂物;添加铝的高碳铬铁组织致密,气孔率小,而常规高碳铬铁存在大量裂纹和孔洞,组织疏松,添加硅铁粉的高碳铬铁介于两者之间;经颚式破碎机破碎后,常规高碳铬铁、添加硅铁粉的高碳铬铁和添加铝的高碳铬铁破碎后粉末率分别为13.2%、11.7%和9.5%。

In order to study the variation of the solid phase microstructure and breaking properties of high carbon ferrochromium alloy in teeming process with silicon iron powder and aluminum addition,the high carbon ferrochromium produced by a ferroalloy corporation was remelted in a 0.2 tmultifunctional pilot-scale steelmaking furnace.Aluminum and ferrosilicon powder were added respectively during teeming process.And the solid phase microstructure of the conventional high carbon ferrochromium and high carbon ferrochrome with addition of aluminum and ferrosilicon powder was analyzed.The sample was broken by jaw crusher.The results showed that the microstructure of high carbon ferrochromium was mainly composed of(Cr,Fe)7C3 solid phase and(Cr,Fe)7Si solid phase,and some TiN,MnS and Al2O3 inclusions were precipitated.The Al2O3 inclusions were not found in the conventional high carbon ferrochromium.While,the Al2O3 inclusions and TiN were precipitated in the high carbon ferrochromium with adding ferrosilicon powder and aluminum.After adding aluminum in the high carbon ferrochromium,the structure was dense,and its porosity was small,while there were a large number of cracks and holes in the conventional high carbon ferrochromium,whose microstructure was loose.And the properties of the high carbon ferrochromium with ferrosilicon powder were between the above two.After broken by the jaw crusher,the powder rate of the conventional high carbon ferrochromium,the high carbon ferrochromium with ferrosilicon powder and aluminum,was13.2%,11.7% and 9.5%,respectively.