Effect of aluminum on the tribological behavior of Hadfield steel in the mild wear condition

In this paper, the effect of aluminum addition on the tribological behavior of Hadfield steel in mild wear condition was investigated. The pin-on-disk test method was used on the different compositions of Hadfield steel that alloyed by three nominal compositions of zero, 1.5 and 3 weight percent of aluminum. The experimental induction furnace surrounded by Ar atmosphere and zirconia ceramic mold was used for melting and casting of samples. In the wear test, the grinding wheel as abrasive medium was used and the changes in the friction coefficient and the weight losses of specimens versus the sliding distance were measured. The tensile, hardness and impact tests were used for evaluation of mechanical properties. In addition, the microscopically studies on the deformed samples, worn surface and wear debris were done using optical and scanning electron microscopes. The results shown that in the low stress wear condition, the work-hardening of worn surface of Hadfield steel cannot well be activated, therefore it has not sufficient wear resistant. By addition of 3wt. % aluminum, the yield strength from 415MPa to 470MPa and hardness from 190HV to 215HV can be increased. In addition, depth of work-hardened on abrasive forces and worn surface hardness can be enhanced from 100µm to 200µm and from 340HV to 365HV in sequence. Thus the wear rate from 0.15mg/m to 0.11mg/m was decreased and wear resistance was improved up to 70%.