表面力測定装置を用いて評価した粉末冶金用固体潤滑剤の接着性および摩擦特性

抄録

Iron-based powder mixtures for the powder metallurgy (PM) process commonly contain solid lubricants. Both zinc stearate (ZnSt) and N,N’-ethylenebis(stearamide) (EBS), which are conventional lubricants in this field, exhibit the similarly adequate lubrication performances. However, their effects on the powder mixture flow ability are different; that is, ZnSt exhibits the better flow abilities than EBS. In this study, the adhesive and frictional properties of the five surface combinations (Fe-Fe, Fe-EBS, Fe-ZnSt, EBS-EBS, and ZnSt-ZnSt) were investigated using surface forces and resonance shear measurement. The adhesion forces obtained for all combinations were almost the same. On the other hand, frictions for Fe-EBS and EBS-EBS combinations, obtained from resonance shear measurement, were larger than others at low applied load (<ca. 1.0 mN). This result suggests that the frictional properties of lubricants at low applied load determine the powder mixture flow abilities.