【摘要】 将球团矿和煤粉混合装料，使球团矿被煤粉包裹，在固态下进行直接还原，新生的直接还原铁将发生渗碳，渗碳现象使生成的直接还原铁表面熔化，形成致密的金属外壳，堵塞了直接还原铁的微气孔，在热态氧化气氛下，这层致密的金属外壳起到防止直接还原铁再氧化的作用。更多还原

【Abstract】 Pellet sample is wrapped up by coal powder and reduced directly in solid state When the reduction finished, carbonization will take place due to the close contact between the hot DRI and coal powder, which results that the surface of hot DRI melted and formed a layer of compact metallic shell This shell can protect hot DRI from re oxidization at high temperature in the air更多还原