淬火工艺对铬结构钢显微组织和力学性能的影响

研究了淬火工艺对低和中碳铬钢的显微组织、冲击韧性和断裂机制的影响．结果表明，提高淬火温度，使中碳钢所获得的、带方向性的纤维状马氏体和呈等边三角形出现的马氏体都是孪晶型的片状马氏体．低碳淬火钢中有相当数量的板条马氏体中也都带有孪晶．并证实，具有细小奥氏体晶粒的细片马氏体或隐针马氏体的冲击韧性值高于粗大的低碳板条马氏体．因此，无论是低碳，还是中碳和高碳钢，当奥氏体晶粒长大倾向稍大时，采取提高加热温度进行淬火的工艺是不可取的

THE EFFECT OF QUENCHING PROCESSING ON THE MICROSTRUCTURE AND MECHANICAL PROPERTIES OF STRUCTURAL STEEL CONTAING Cr ELEMENT

The effect of quenching processing on the microstructure, shock toughness and fracture mechanism of low and medium carbon steels was investigated in detail. It is found that the directive fiberized martensite, and triangular martensite gained after quenching at elevated temperature are plate martensite with twin substructure for medium carbon steel. As for low carbon steel, there are more twins in the martenstic laths. It is proved that fine plate martensite formed from fine austenite grains have shown higher shock toughness than that of coarse martensite for low carbon steel. Thus, the quenching processing in which heating temperature is higher is worse because large austenite grains would hurt the mechanical properties of materials for any caron steel.