Effect of the coal tar pitch modified by sulfur as binder on the mechanical and tribological properties of bronze-impregnated carbon-matrix composites
Bronze-impregnated carbon-matrix composites were prepared through compression molding,carbonization and impregnation.The mechanism of sulfuration was studied and the effect of coal tar pitch modified by sulfur as binder on the mechanical and tribological properties of composites was investigated by varying the content of sulfur.The results showed that sulfur addition increased the softening point,the carbon yield and the C/H atomic ratio of coal tar pitch but decreased the toluene solubility and quinoline solubility due to the dehydrogenating polymerization of pitch molecules.The micro-hardness,bending strength and compressive strength of the composites enhanced with increasing the mass percentage of sulfur and reached a maximum of 160 HV,132.82 MPa and 293 MPa at 7 wt.% of sulfur,respectively.However,both hardness and strength of the composites decreased as the content of sulfur was beyond 7 wt.%.The friction coefficient value of composites rose monotonously but the wear rate decreased with increasing the content of sulfur,subsequently the wear rate reached a minimum of 3.045×10-7 mm3/Nm at 7 wt.% of sulfur,and then ascended.The wear mechanism of the composites was adhesive wear,abrasive wear and oxidative wear.However,adhesive wear and oxidative wear occurred slightly for the composites with the binder modified by sulfur.
Hardness measurement mechanical characterization composites wears
Yang Huijun
Research Institute of Surface Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China
国际会议
上海
英文
48-48
2012-10-19（万方平台首次上网日期，不代表论文的发表时间）