How have we come to have the magnet materials that we have today? This chart walks us through the development over the past century. As we see, the strength of magnets has increased dramatically over the past 50 years. Keep in mind that the strength of the magnets is only one design consideration. For many high-tech, and especially defense applications, factors other than magnet strength come into play. In other words, when you are working in extreme environments, designing with magnets is not a simple task. Historically, Alnico was one of the first permanent magnet materials that enabled engineers to incorporate magnets into a wide range of applications. Due to their lower cost, ferrites eventually took over most of the more mundane applications, including audio speakers. As other magnet materials were developed, the four main materials each found a unique performance niche. Now let me begin to draw a picture of what the US magnet industry looks like today. I’ll start with briefly describing my company,
The unique characteristics of each make it a viable product for today’s market
Ferrites, while not considered high performance, are by far the most widely used magnets in the world The three high performance permanent magnet materials are represented today on our panel. My company, Thomas & Skinner, makes alnico magnets in Indianapolis, Indiana
With casting, you’re pouring molten melt into a mold with the part shapes. This is a somewhat inefficient process, due to the relatively low amount of parts yielded as compared to the amount of metal poured. Process does provide dense parts, and therefore the strongest magnetic properties.
Using the sintering process, parts can be made more efficiently, but typically do not have as strong of magnetic properties due to a lower density.
April 6, 2009 issue of Business Week stated (paraphrasing): While each year some companies invariably ride the wave of powerful industry cycles, many more earned their spot in the BW 50 as innovators.
