The fracture and spheroidization of cementite shows obvious anisotropy . there are two possible mechanism about spheroidization of cementite : the fracture cementite lamellae grows up non - uniformly and the fine spherical cementite particles grows up as the core 渗碳体的破碎和球化表现出明显的各向异性。渗碳体的球化可能以两种机制进行:破碎渗碳体片的非均匀长大和细小球状渗碳体颗粒的形核长大。