SURFACE-PROPERTIES AND PARTICLE INTERACTIONS OF METAL MAGNETIC POWDERS

Two types of metal magnetic powders, referred to as powder A and powde r B, were analyzed in terms of their surface properties and interparti cle interaction characteristics. Surface chemical compositions were de termined by using electron spectroscopy for chemical analysis. The maj or distinction in the surface compositions was that particles of powde r A had excess aluminum, whereas those of powder B had excess silicon and carbon, Wettability of powder A as measured by the contact angle m ethod and capillary penetration method was better than powder B. Diele ctric properties, magnetic hysteresis and remanence curves were measur ed to identify the values of electric and magnetic interparticle inter action parameters. Electric particle interactions as given by the pola rizability was greater for powder A than for powder B. Average values of parameters indicating magnetic particle interactions were nearly eq ual for both powders, a comparison of electric versus magnetic interac tion parameters of individual samples indicated that these two differe nt types of particle interactions correlated with each other.