离心铸造WC_p/Fe-C复合材料及其应用研究

WC_p/Fe-C composites with centrifugal casting and their application

通过扫描电镜、电子能谱分析,研究了离心铸造复合材料辊环的机械性能,微观组织及其应用。结果表明:在离心铸造条件下制备的WCp/Fe C复合材料辊环,其复合材料工作层的硬度达到HRA80～85,接近了粉末冶金辊环的硬度(HRA81～88),复合材料工作层和芯部贝氏体基体的冲击韧性ak值分别达到5.4和14.8J/cm2。高于粉末冶金辊环的韧性(1.6～3.0J/cm2)。辊环复合材料工作层中增强颗粒的体积分数和复合材料工作层厚度均受离心转速和浇注温度影响。在离心转速>1200r/min、浇注温度>1500℃时,可制备复合材料工作层厚度18～24mm、WCp体积分数80%、界面结合良好没有微观和宏观裂纹缺陷的复合材料辊环。

The mechanical properties, microstructures and application of centrifugal casting composites roller ring have been investigated by SEM EDS-analysis in the paper. The results show that the hardness of WCp/Fe-C composites work layer was of HRA80-85. The impact toughness of the composites work layer and matrix alloy core of roller rings attained 5.4 J/cm2 and 14.8 J/cm2 respectively, which are higher than that of the power metallurgical roller rings. Both volume fraction of WCp and thickness of WCp/Fe-C composites work layer were affected by rotating speed of centrifugal casting and the casting temperature. The thickness of WCp/Fe-C composites work layer of the roller ring was of 18-24 mm, the volume fraction of WCp was about 80 vol%. And the good interface combination between WCp and the matrix has been made when rotating speed of centrifugal casting was over 1200 r/min and the casting temperature over 1500°C. The transition layer between WCp/Fe-C composites work layer and matrix alloy core was perfect. In the transition layer, there are no micro-or macro-cracks and any defects.