Flexural strength of the injected dielectromagnets
Lech Paszkowski, Waldemar Wiśniewski Politechnika Warszawska, Wydział Mechatroniki, Instytut Inżynierii Precyzyjnej i Biomedycznej, ul. św. A. Boboli 8, 02-525 Warszawa, Poland
Quarterly No. 4, 2007 pages 185-190
DOI:
keywords: flexural strength, dielectromagnets, injection
abstract Injection molding is one of the production methods of dielectromagnets. This technology was applied in presented researches. Special molded samples were prepared for analysis of flexural strength. They were made of composites base on the thermoplastic polymer with hardmagnetics powders. The flaky powder MQP-B and spheroidal powder MQP-S made from magnetic alloy Nd-Fe-B were used. As polymer matrix two kinds of polystyrene: the high impact and low impact polystyrene were used. The powders were produced by Magnequench International USA and polymers by DWORY S.A. Poland. Composites were made by the solvent method using toluene. The composites consist variable volume fraction of the flaky and spheroidal powder also separate granularity of the both kinds of powders. The feedstock temperature during injection was of 200oC and pressure of injection was of 110 MPa. In this paper, the correlation between flexural stress and deflexion for samples made of composites inclusive 48% of flaky and spheroidal powder is presented. More over the influence of the volume fraction, grain size and kind of magnetic powders was shown. Additionally investigation of fractures view made from composites with flaky and spheroidal powder were carried out. The analyze of the received results showed, that the most influence on the flexural strength had the kind of the polystyrene and shape of magnetic powder particles used for samples preparation.