机械合金/固态反应法制备高性能铁芯

Sendust and Superpermalloy Nanoparticles Prepared by Mechanical Alloying

铁硅铝及铁镍钼合金具有低磁伸缩系数、低磁异方性常数及比纯金属高的电阻系数,非常适合于制作高性能铁芯.此铁芯通常以合金粉末为原料,由粉末冶金法制成.由于合金粉末通常采用喷雾法或化学还原法制作,需要庞大的设备及先进的技术,一般铁芯制造工厂不易自行制造,铁硅铝及铁镍钼合金粉末属特殊规格,国际上也不容易购得,限制了金属质铁芯工业的发展.为解决此一问题,拟以机械合金/固态反应法,以纯金属粉末为原料,制作此铁芯,其制作过程把纯金属粉末经混合及研磨数十多小时,制成半机械合金粉末,粉末表面经绝缘处理后,再经过成型及氢气炉烧结,制成铁芯.在烧结过程中,未完全反应的粉末继续反应成合金.所拟开发的技术尚属首创,其优点为不需投资喷雾法或化学还原法的制粉设备,以现成的研磨罐即可制作机械合金,设备简单,原料便宜.另一优点为半机械合金粉末比全合金粉末软,可以压成高密度及高强度的胚体,烧结后的铁芯磁性较佳.如果成功,将根本改变铁芯的制作技术,改变数十亿铁芯市场的制作成本及成品质量.

Sendust and superpermalloy with low magnetostriction,low anisotropic constant and high resistivity compared with pure metals are appropriate for high quality magnetic cores.These cores are made of the corresponding metal powders which are prepared by spraying or chemical reduction methods.No alloy core company is in Taiwan.In this study,these powders are prepared by mechanical alloying/solid state reaction method.In the grinding process,the crystallized phase changes of the mixed metal powders are measured by XRD.Fe-Si-Al alloy core and Ni-Fe-Mo alloy core are hard pressed out from the as-prepared mechanical alloying powders which are annealed at 700℃.The permeability of Sendust and supermalloy is 14432 and 18360 at 120 Hz respectively.