Nihon Denji Sokki sees an opportunity for disruption in this industry, as the production of high-performance magnets is currently dominated by labor-intensive two-step die pressing systems. Our single step reduced isostatic pressure molds have already made significant progress in response to market trends, realizing better controllability and higher levels of automation over the whole process. Let us put our knowhow to work for you in finding cutting edge solutions for your use cases.

On Going Challenges

The universal adoption of single step die pressing technologies is being delayed by intellectual property issues, the poor quality of magnetic powders & their additives, and the inconsistency of the equipment available within the current installed base. The suitability of mold designs, or the capabilities of existing processes also must be considered when providing solutions for different use cases.

We have developed these automated systems for producing NdFeB sintered magnets, but our designs are flexible enough to serve a wide range of use cases involving the sintering of powdered materials: including compacting titanium alloys or ceramic powders. Magnets pressed in our isostatic rubber molds offer good alignment because pressure is applied equally over all degrees of freedom. Since the powder is then prevented from shifting with respect to the inner wall of the mold during the press, good alignment is obtained.

In a typical press system, there needs to be at least four stages; 1) fill -- magnetic powder injection into the mold, 2) pressing, 3) extraction, and 4) cleaning. The RIP Press shown in the figure utilizes a six-stage process that has been optimized for NdFeB magnet production. In addition to the four basic stages, a magnetic field orientation stage and one more cleaning stage are also required. Our presses have the option for an encoded turntable, which tracks the rubber molds as they move through each of these stages.

Advantages

Our efforts have succeeded in the development of a fully automated sintering furnace for the mass production of rare earth element magnets (REE magnets). Our furnace is capable of sintering ferrous metal powders in a near oxygen-free environment (levels below 50 ppm). The press boasts of an automated material handling process and a mold stacking feature with a conveyor system that continuously feeds material to the furnace. This system is also fully traceable and compatible with computerized manufacturing execution systems (MES).

Features & Capabilities