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研究了成分、铸造工艺及空冷工艺对新型空冷贝氏体耐磨铸钢力学性能的影响。结果表明，硅能显著提高贝氏体铸钢的冲击韧性。与低硅贝氏体铸钢相比，在相同硬度的前提下，添加硅能使贝氏体铸钢的韧性提高１倍以上。通过透射电镜观察发现，韧性提高的主要原因是较高的硅含量能抑制贝氏体中碳化物的析出，即用高韧性的残余奥氏体代替脆性的渗碳体。研究还表明，钢中碳含量、铸造工艺及空冷工艺对贝氏体铸钢的强韧性影响极大。采用中低碳、高硅及适当的铸造工艺和空冷工艺可使贝氏体铸钢有优良的强韧性配合：ＨＲＣ≥４５，ａｋ＝３０～５０Ｊ／ｃｍ２（１０ｍｍ×１０ｍｍ×５５ｍｍ，Ｕ型缺口）。
The effects of composition, casting process and air cooling process on the mechanical properties of a new air-cooled bainitic wear-resistant cast steel were studied. The results show that silicon can significantly improve the impact toughness of bainitic cast steel. Compared with low-silicon bainitic cast steel, under the same hardness premise, adding silicon can make bainitic cast steel toughness more than doubled. Transmission electron microscopy showed that the main reason for the increase in toughness is the higher silicon content that inhibits the precipitation of carbides in the bainite, ie, the replacement of brittle cementite with highly ductile retained austenite. The research also shows that the carbon content in steel, casting process and air cooling process greatly affect the toughness of bainitic cast steel. The use of low carbon, high silicon and appropriate casting process and air cooling process can make bainitic cast steel has excellent toughness with: HRC ≥ 45, ak = 30 ~ 50J / cm2 (10mm × 10mm × 55mm, U-notch ).